MAP7 (Ensconsin): A Multifunctional Microtubule-Associated Protein and Essential Kinesin-1 Cofactor

Introduction

Microtubule-associated protein 7 (MAP7), also known as ensconsin or E-MAP-115, is a ubiquitously expressed microtubule-associated protein that plays fundamental roles in microtubule organization, motor protein regulation, and intracellular transport. The protein was first isolated and characterized from HeLa cells by Bulinski and Bossler in 1994, who named it "ensconsin" because of its remarkably tenacious binding to microtubules—the term deriving from "ensconce," meaning to settle snugly or securely [bulinski-1994-ensconsin-abstract]. Independently, the same protein was identified as E-MAP-115 (epithelial microtubule-associated protein of 115 kDa) due to its prominent expression in epithelial cells.

MAP7 has emerged as a critical regulator of the kinesin-1 motor protein, functioning not merely as a passive microtubule-binding factor but as an essential cofactor required for kinesin-1-mediated cargo transport [barlan-2013-kinesin-cofactor-abstract]. This dual function—simultaneously associating with microtubules and activating motor proteins—positions MAP7 as a key coordinator of intracellular transport systems. The protein is encoded by the MAP7 gene located at chromosome 6q23.3 in humans and belongs to a family that includes three paralogs in mammals: MAP7D1, MAP7D2, and MAP7D3, with MAP7D1 showing the highest sequence conservation to the founding member [hooikaas-2019-map7-family-abstract].

Protein Structure and Domain Organization

Human MAP7 is a 749-amino acid protein with a predicted molecular mass of approximately 84 kDa, although it migrates anomalously at 115 kDa on SDS-PAGE due to its high content of proline and charged residues [bulinski-1994-ensconsin-abstract]. The protein is organized into three principal domains: an N-terminal domain containing the first coiled-coil region (CC1) that mediates microtubule binding, a central P domain (proline-rich region) containing numerous potential phosphorylation sites, and a C-terminal domain containing the second coiled-coil (CC2) that interacts with kinesin-1 [tymanskyj-2018-axon-morphogenesis-abstract].

The N-terminal basic region is separated from an acidic C-terminal half by a stretch of amino acids rich in proline and alanine (termed the PAPA region). The N-terminal basic domain contains the primary microtubule-binding site, and detailed structural analysis has revealed that MAP7 exhibits binding that saturates its microtubule binding sites at an approximate molar ratio of 1:6 (ensconsin:tubulin) [bulinski-1994-ensconsin-abstract]. Unlike other characterized MAPs such as tau, MAP2, and MAP4, ensconsin's binding to microtubules displays remarkable salt resistance, remaining insensitive to moderate salt concentrations up to 0.6 M, suggesting a biochemically and functionally distinct mode of microtubule interaction.

Recent structural studies using cryo-electron microscopy and NMR spectroscopy have provided atomic-level insights into how MAP7 binds microtubules. The microtubule-binding domain (MTBD) forms a 130 angstrom-long alpha helix extending from approximately residue R66 to E148 that binds along the microtubule protofilament between the outer protofilament ridge and the inter-protofilament lateral contacts [adler-2024-mtbd-structure-abstract, ferro-2022-kinesin-structure-abstract]. Importantly, both strong and weak interactions between MAP7 and the microtubule lattice extend beyond a single tubulin dimer and include the tubulin C-terminal tails, which may contribute to the protein's unusually stable microtubule association.

Microtubule Binding and Stabilization

Early characterization established ensconsin as a potent microtubule-stabilizing protein in vitro, capable of protecting microtubules against depolymerization by cold and calcium [bulinski-1994-ensconsin-abstract]. Immunofluorescence studies demonstrated ensconsin association with most or all microtubules in human epithelial, fibroblastic, and muscle cells. However, subsequent studies using fluorescent protein-tagged E-MAP-115 revealed a more nuanced picture of its function in living cells. Faire and colleagues demonstrated that E-MAP-115 "associated with the lattice of all microtubules immediately upon polymerization and dissociated concomitant with depolymerization" [faire-1999-emap115-dynamics-abstract]. Remarkably, even when cells expressed four to ten times normal levels of the protein, microtubule dynamics remained unchanged, leading the authors to conclude that "E-MAP-115 (ensconsin) is unlikely to function as a microtubule stabilizer in vivo" under normal physiological conditions.

This apparent paradox—potent stabilization in vitro but minimal effect on dynamics in vivo—has been resolved by more recent work demonstrating context-dependent functions of MAP7. In neuronal cells, MAP7 plays a critical role in microtubule stabilization specifically at branch junctions. Studies in developing rodent sensory neurons showed that MAP7 "binds to the acetylated and stable region of individual microtubules" and creates a stable boundary that prevents depolymerization while rescuing polymerization [tymanskyj-2019-branch-retraction-abstract]. This binding property is distinct from classical microtubule stabilizers in that MAP7 does not uniformly coat microtubules but rather preferentially associates with stable, acetylated segments while avoiding the dynamic plus ends containing tyrosinated tubulin. This selective binding creates a molecular boundary that protects branch junctions from retraction during axonal development.

Kinesin-1 Activation and Recruitment

Perhaps the most significant function of MAP7 is its role as an essential cofactor for kinesin-1-mediated intracellular transport. Groundbreaking work by Barlan and colleagues demonstrated that "kinesin-1 requires ensconsin (MAP7, E-MAP-115), a ubiquitous microtubule-associated protein, for its primary function of organelle transport" [barlan-2013-kinesin-cofactor-abstract]. Using RNAi-mediated depletion in Drosophila S2 cells, they showed that ensconsin is critical for kinesin-1-dependent transport of mitochondria, peroxisomes, and ribonucleoprotein particles. Homozygous ensconsin deletion mutants cannot survive to adulthood, and this lethality results from a requirement for ensconsin in neuronal transport.

The mechanism by which MAP7 activates kinesin-1 involves relief of the motor's autoinhibition. In the absence of cargo or activating factors, kinesin-1 exists primarily in an inactive, autoinhibited conformation where the tail domain folds back to inhibit the motor domains. Importantly, unregulated kinesin-1 mutants that bypass autoinhibition do not require ensconsin for transport, demonstrating that ensconsin functions to relieve this autoinhibited state [barlan-2013-kinesin-cofactor-abstract]. Remarkably, an ensconsin N-terminal truncation that cannot bind microtubules is sufficient to activate organelle transport by kinesin-1, indicating that the activation function is separable from microtubule binding.

The C-terminal domain of MAP7 containing the second coiled-coil (CC2) mediates interaction with the stalk region of kinesin-1. This interaction both recruits kinesin-1 to microtubules and activates its motor activity. In vitro studies by Hooikaas and colleagues demonstrated that purified MAP7 increases the microtubule landing rate and processivity of kinesin-1 through transient association with the motor [hooikaas-2019-map7-family-abstract]. All four mammalian MAP7 family members bind kinesin-1 and work redundantly in HeLa cells to enable kinesin-1-dependent transport and microtubule recruitment.

Structural studies have revealed an unexpected complexity in how MAP7 regulates kinesin-1. The microtubule-binding domain of MAP7 partially overlaps with the binding site for kinesin-1 on the microtubule surface, creating a biphasic regulatory mechanism [ferro-2022-kinesin-structure-abstract]. At low MAP7 concentrations, facilitation of kinesin-1 motility dominates because MAP7's projection domain tethers the motor to the microtubule and prevents dissociation. At saturating MAP7 concentrations, however, inhibition predominates due to reduced available binding sites on the microtubule. This concentration-dependent regulation provides a mechanism for fine-tuning motor protein activity in different cellular contexts.

Role in Organelle Transport and Motor Protein Competition

MAP7 profoundly influences the directionality and efficiency of organelle transport. Chaudhary and colleagues demonstrated that in the absence of MAP7, isolated phagosomes move equally in both directions along microtubules [chaudhary-2019-organelle-transport-abstract]. However, MAP7 dramatically shifts transport toward the microtubule plus-end, with approximately 80% of movements becoming plus-end directed. This bias does not result from changes in individual motor force output but rather from increased binding rates of kinesin-1 motors to microtubules, allowing more motors to engage simultaneously during cargo transport.

An important aspect of MAP7 function is its competitive relationship with other microtubule-associated proteins, particularly tau. Monroy and colleagues demonstrated that MAP7 and tau "compete for binding to microtubules" with MAP7 capable of displacing tau from the microtubule lattice [monroy-2018-map-competition-abstract]. The binding affinity of MAP7 for microtubules (KD = 0.47 +/- 0.06 microM) exceeds that of tau (KD = 1.56 +/- 0.16 microM), favoring MAP7 association when both proteins are present. This competition has functional consequences for motor protein recruitment: MAP7 promotes kinesin-1-based transport while both MAP7 and tau strongly inhibit kinesin-3 activity. Neither protein affects cytoplasmic dynein motility. This differential regulation of motor proteins by competing MAPs provides a mechanism for establishing distinct transport pathways in different cellular compartments.

The spatial segregation of MAP7 and tau in neurons supports this model of competitive regulation. In both Drosophila peripheral nervous system neurons and primary mouse neuronal cultures, MAP7 localizes within both dendrites and axons, while tau is predominantly restricted to axons [monroy-2018-map-competition-abstract]. This distribution suggests that MAP competition helps dictate access to microtubules and determines the correct distribution and balance of motor activity in polarized cells.

Neuronal Functions and Axon Morphogenesis

MAP7 plays essential roles in neuronal development, particularly in axon and branch morphogenesis. Structure-function analysis in rat embryonic sensory neurons demonstrated that different MAP7 domains serve distinct functions in neurite development [tymanskyj-2018-axon-morphogenesis-abstract]. The C-terminal kinesin-interacting domain is required for axon and branch growth but not for branch formation, while both the N and P domains, which bind microtubules with different dissociation kinetics, are required for branch formation. MAP7 localizes specifically to branch sites through its N and P domain interactions.

Developmentally, MAP7 expression is regulated during sensory neuron maturation, and perturbation of this expression alters branch formation [tymanskyj-2018-axon-morphogenesis-abstract]. The protein enters nascent branches with a characteristic delay, consistent with a role in branch maturation rather than initiation. This delayed entry correlates with its preferential binding to stable, acetylated microtubules rather than the dynamic tyrosinated microtubules at growing tips.

MAP7 also modulates organelle transport dynamics within neurons. Expression of MAP7 increases the pause frequency and promotes directional switching during kinesin-mediated mitochondrial and peroxisomal transport [tymanskyj-2018-axon-morphogenesis-abstract]. This suggests a mechanism for diverting organelles into axon branches: by recruiting kinesin-1 to microtubules at branch points and promoting pause-speed switching, MAP7 may facilitate the delivery of cellular cargo to developing branch compartments.

Muscle Function and Nuclear Positioning

Beyond neurons, MAP7 performs critical functions in skeletal muscle. Metzger and colleagues identified ensconsin/MAP7 and kinesin heavy chain (Khc/Kif5b) as "essential, evolutionarily conserved regulators of myonuclear positioning" in both Drosophila and mammalian myotubes [metzger-2012-nuclear-positioning-abstract]. In multinucleate muscle fibers, individual nuclei must be regularly positioned throughout the cell, and improperly positioned nuclei are a hallmark of diseases including centronuclear myopathies.

The physical interaction between MAP7 and kinesin enables nuclear positioning through a mechanism involving sliding of antiparallel microtubules. MAP7 crosslinks a microtubule to the tail of kinesin-1, which then reaches toward a second, antiparallel microtubule. The motor activity slides the two microtubules apart, resulting in nuclear spreading. Expression of the Kif5b motor domain fused to the MAP7 microtubule-binding domain rescues nuclear positioning defects in MAP7-depleted cells, demonstrating that both activities—motor function and microtubule binding—are required for this process.

Drosophila larvae with mutations in ensconsin display decreased locomotion and incorrect myonuclear positioning, phenotypes that can be rescued by muscle-specific expression of ensconsin [metzger-2012-nuclear-positioning-abstract]. This establishes that proper nuclear organization directly contributes to muscle function in a cell-autonomous manner.

Epithelial Cell Differentiation and Polarization

MAP7 was originally named E-MAP-115 to reflect its predominant expression in cells of epithelial origin. The protein plays important roles during reorganization of microtubules during epithelial cell polarization and differentiation. Expression levels increase with epithelial cell polarization and differentiation, and the protein may contribute to the formation of intercellular contacts [vanier-2003-emap115-epithelial-abstract].

In human intestinal epithelial cells, three E-MAP-115 transcript variants encode isoforms of 115, 105, and 95 kDa, with distinct expression patterns during cell maturation. Two isoforms display an expression gradient inverse to the third as Caco-2 cells progress from proliferation through differentiation stages. In vivo, these proteins are expressed in both crypt and villus epithelial cells where they concentrate at the apical pole, consistent with a role in establishing or maintaining apical-basal polarity [vanier-2003-emap115-epithelial-abstract].

Role in Spermatogenesis

E-MAP-115/MAP7 plays a critical role in male fertility, as demonstrated by gene trap mutagenesis studies in mice. Komada and colleagues identified E-MAP-115 as a retinoic acid-inducible gene with particularly high expression in testis [komada-2000-spermatogenesis-abstract]. Male mice homozygous for a null mutation in the E-MAP-115 gene were sterile due to morphological deformation of spermatid nuclei and subsequent gradual loss of germ cells. Importantly, microtubule associations in the mutant were morphologically abnormal in two critical structures: the manchette of spermatids and in Sertoli cells.

The manchette is a transient microtubule-based structure that forms around the elongating spermatid nucleus and is essential for nuclear shaping during spermiogenesis. Sertoli cells, which provide structural and nutritional support to developing germ cells, also rely on intact microtubule networks. The observation that E-MAP-115 mutation disrupts microtubules in both cell types is consistent with the protein's role in stabilizing microtubules and suggests that this function is particularly critical in the testicular microenvironment where complex morphological transformations depend on microtubule integrity.

The connection to retinoic acid signaling is noteworthy because retinoic acid is a critical regulator of spermatogenesis, governing the differentiation of spermatogonia, meiotic entry, and the timing of sperm release. The identification of E-MAP-115 as a retinoic acid-responsive gene positions it within this regulatory network, suggesting that microtubule organization during spermatogenesis is coordinated with broader developmental signals [komada-2000-spermatogenesis-abstract].

Wnt Signaling and Cell Migration

Recent work has revealed an unexpected connection between MAP7 family proteins and non-canonical Wnt signaling. Kikuchi and colleagues demonstrated that MAP7 and MAP7D1 form an interdependent regulatory loop with Dishevelled (Dvl), the central signal transducer in Wnt pathways [kikuchi-2018-wnt-signaling-abstract]. In HeLa cells, MAP7/7D1 bind directly to Dishevelled, direct its cortical localization, and facilitate the cortical targeting of microtubule plus-ends in response to Wnt5a signaling.

This interaction is bidirectional: Wnt5a signaling promotes MAP7/7D1 movement toward microtubule plus-ends through a mechanism involving the kinesin-1 member Kif5b, while Dishevelled reciprocally stabilizes MAP7/7D1 proteins. Depletion of MAP7/7D1 causes failure in cortical targeting of microtubule plus-ends, which in turn leads to reduced actin and focal adhesion dynamics, ultimately resulting in defects in cell migration and adhesion [kikuchi-2018-wnt-signaling-abstract].

The evolutionary conservation of this mechanism is supported by studies in Drosophila, where the MAP7 ortholog ensconsin shows planar-polarized distribution in pupal wing epithelial cells and is required for proper localization of Drosophila Dishevelled (Dsh). Similarly, in mouse oviduct epithelial cells, MAP7/7D1 display planar-polarized distribution. This conservation across species suggests that the MAP7-Dishevelled interaction represents an ancient mechanism linking microtubule organization to planar cell polarity signaling.

DNA Damage Response

An unexpected function of MAP7 has emerged from proteomic studies examining the DNA damage response. Dullovi and colleagues discovered that MAP7 and MAP7D1 interact with several DNA repair proteins, including the double-strand break repair factors RAD50, BRCA1, and 53BP1 [dullovi-2023-dna-repair-abstract]. These interactions are phosphorylation-dependent and regulated by the kinase CK2, with the interaction domain mapping to residues 144-300 of MAP7.

Functional studies revealed that downregulation of MAP7 and MAP7D1 leads to increased phosphorylation of p53 after gamma-irradiation, indicating enhanced DNA damage signaling. Furthermore, depletion of MAP7D1 causes a strong G1 cell cycle arrest, and knockdown of MAP7 and MAP7D1 in G1-arrested cells negatively affects DNA repair efficiency, recruitment of RAD50 to chromatin, and localization of 53BP1 to sites of damage [dullovi-2023-dna-repair-abstract].

These findings describe a novel function for MAP7 family proteins in cell cycle regulation and repair of DNA double-strand breaks, particularly during G1 phase when homologous recombination is unavailable and cells rely on non-homologous end joining. The mechanism by which cytoplasmic microtubule-associated proteins influence nuclear DNA repair processes remains to be fully elucidated but may involve trafficking of repair factors or coordination of cytoplasmic and nuclear responses to genotoxic stress.

Cell Cycle Regulation and Mitosis

MAP7 function is regulated by phosphorylation during the cell cycle. During interphase, the protein is phosphorylated only on serine residues, but during mitosis it becomes phosphorylated on threonine as well. Ten Cdk1 phosphorylation sites (T/SP motifs) have been identified, six of which are located within the microtubule-binding domain. Phosphorylation of MAP7 downstream of Cdk1/cyclin B leads to inactivation of the protein in prophase, contributing to the reduction in interphase microtubule stability that is necessary for proper spindle assembly. Failure to destabilize microtubules in prophase leads to formation of microtubule clumps that interfere with spindle morphogenesis.

In Drosophila neural stem cells, MAP7/ensconsin promotes microtubule growth and centrosome separation, indicating a positive role in mitotic spindle organization. The protein helps control the length of microtubules in the mitotic spindle, contributing to proper chromosome segregation.

Subcellular Localization

MAP7 localizes primarily to the cytoplasm in association with microtubules. The protein shows a dynamic association with microtubules, binding rapidly to newly polymerized microtubule lattice and dissociating upon depolymerization [faire-1999-emap115-dynamics-abstract]. In polarized epithelial cells, MAP7 concentrates at the apical pole where microtubule organizing centers are typically located.

In neurons, MAP7 localizes throughout dendrites and axons but shows enrichment at specific sites including branch junctions. The protein preferentially associates with stable, acetylated microtubule segments while avoiding the dynamic plus ends, creating a characteristic spatial distribution along the microtubule lattice [tymanskyj-2019-branch-retraction-abstract].

In muscle cells, MAP7 associates with microtubules that connect adjacent nuclei, facilitating the sliding mechanism that positions nuclei appropriately within multinucleate fibers [metzger-2012-nuclear-positioning-abstract].

Evolutionary Conservation

The MAP7/ensconsin protein family is highly conserved across metazoans, with clear orthologs identified in both vertebrates and invertebrates. The Drosophila ensconsin protein shares significant sequence similarity with mammalian MAP7/E-MAP-115, particularly in two conserved regions designated ensconsin homology region 1 (EHR1) and EHR2. The N-terminal EHR1 region corresponds to the microtubule-binding domain, while EHR2 encompasses the C-terminal kinesin-binding region. Both mammalian and Drosophila proteins generate multiple isoforms through alternative splicing, particularly in the regions flanking EHR1 [barlan-2013-kinesin-cofactor-abstract].

Functional studies have confirmed that the essential role of ensconsin/MAP7 as a kinesin-1 cofactor is conserved across species. In Drosophila, ensconsin is required for all known kinesin-1-dependent processes, including proper polarization of the oocyte, nuclear positioning in muscle cells, and neuronal transport. Single-molecule motility assays using Drosophila ovary extract demonstrated that kinesin-1 recruitment to microtubules and subsequent motility are severely impaired without ensconsin [barlan-2013-kinesin-cofactor-abstract]. The phenotypic similarity between Drosophila ensconsin mutants and mammalian MAP7-depleted cells—including defects in myonuclear positioning and kinesin-dependent transport—underscores the ancient origin of this regulatory mechanism.

In mammals, the single ancestral MAP7 gene has undergone duplication to produce a family of four genes: MAP7, MAP7D1, MAP7D2, and MAP7D3. All four family members retain the ability to bind microtubules and interact with kinesin-1, but their distinct expression patterns and subtle biochemical differences suggest functional specialization [hooikaas-2019-map7-family-abstract]. MAP7D1 displays the highest sequence conservation with MAP7, while MAP7D3 has been shown to have higher affinity for kinesin-1 but lower affinity for microtubules compared to MAP7, and uniquely can be cotransported with the motor along microtubules. This diversification of the MAP7 family in mammals may allow for tissue-specific and context-dependent fine-tuning of kinesin-1-mediated transport.

Open Questions

Several important questions about MAP7 function remain to be addressed:

1. Isoform-specific functions: While MAP7, MAP7D1, MAP7D2, and MAP7D3 share the ability to bind microtubules and recruit kinesin-1, their distinct expression patterns suggest non-redundant functions in specific cell types. The precise division of labor among family members, particularly in the nervous system, requires further investigation.

2. Regulation by phosphorylation: Beyond cell cycle-dependent phosphorylation by Cdk1, MAP7 contains numerous potential phosphorylation sites in its P domain. CK2 phosphorylation has been implicated in regulating MAP7 interactions with DNA repair proteins [dullovi-2023-dna-repair-abstract], but how phosphorylation by various kinases modulates MAP7 function across different cellular contexts remains incompletely understood.

3. Role in human disease: While mouse models demonstrate that MAP7 null mutations cause male sterility due to defective spermatogenesis [komada-2000-spermatogenesis-abstract] and defects in nuclear positioning are associated with centronuclear myopathies, direct connections between MAP7 mutations and specific human diseases have not been firmly established. Comprehensive analysis of human genetic variants in MAP7 is lacking.

4. Concentration-dependent effects: The biphasic regulation of kinesin-1 by MAP7—facilitation at low concentrations, inhibition at high concentrations—raises questions about how local MAP7 concentrations are controlled in cells to achieve appropriate motor activity.

5. Mechanism of DNA damage response involvement: The discovery that MAP7 interacts with DNA repair proteins and influences double-strand break repair in G1 phase [dullovi-2023-dna-repair-abstract] raises fundamental questions about how a cytoplasmic microtubule-associated protein contributes to nuclear DNA repair processes.

6. Wnt signaling integration: The reciprocal regulatory relationship between MAP7 and Dishevelled in non-canonical Wnt signaling [kikuchi-2018-wnt-signaling-abstract] suggests broader roles for MAP7 in developmental signaling. How MAP7 coordinates microtubule organization with planar cell polarity establishment across different tissue types warrants further investigation.

7. Therapeutic potential: Given the essential role of MAP7 in kinesin-1-mediated transport, understanding how to modulate this pathway could have implications for neurodegenerative diseases involving transport defects. Whether MAP7 or its interactions with kinesin-1 represent viable therapeutic targets remains to be explored.

References

• [bulinski-1994-ensconsin-abstract]: Bulinski JC, Bossler A. (1994) Purification and characterization of ensconsin, a novel microtubule stabilizing protein. J Cell Sci. 107(Pt 10):2839-49. PMID: 7876351. DOI: 10.1242/jcs.107.10.2839

• [faire-1999-emap115-dynamics-abstract]: Faire K, Waterman-Storer CM, Gruber D, Masson D, Salmon ED, Bulinski JC. (1999) E-MAP-115 (ensconsin) associates dynamically with microtubules in vivo and is not a physiological modulator of microtubule dynamics. J Cell Sci. 112(Pt 23):4243-55. PMID: 10564643. DOI: 10.1242/jcs.112.23.4243

• [metzger-2012-nuclear-positioning-abstract]: Metzger T, Gache V, Xu M, Cadot B, Folker ES, Richardson BE, Gomes ER, Baylies MK. (2012) MAP and kinesin-dependent nuclear positioning is required for skeletal muscle function. Nature. 484(7392):120-4. PMID: 22425998. DOI: 10.1038/nature10914

• [barlan-2013-kinesin-cofactor-abstract]: Barlan K, Lu W, Gelfand VI. (2013) The microtubule-binding protein ensconsin is an essential cofactor of kinesin-1. Curr Biol. 23(4):317-22. PMID: 23394833. DOI: 10.1016/j.cub.2013.01.008

• [vanier-2003-emap115-epithelial-abstract]: Vanier MT, Deck P, Stutzmann J, Gendry P, Arnold C, Dirrig-Grosch S, Kedinger M, Launay JF. (2003) Expression and distribution of distinct variants of E-MAP-115 during proliferation and differentiation of human intestinal epithelial cells. Cell Motil Cytoskeleton. 55(4):221-31. PMID: 12845596. DOI: 10.1002/cm.10124

• [monroy-2018-map-competition-abstract]: Monroy BY, Sawyer DL, Ackermann BE, Borden MM, Tan TC, Ori-McKenney KM. (2018) Competition between microtubule-associated proteins directs motor transport. Nat Commun. 9(1):1487. PMID: 29662074. DOI: 10.1038/s41467-018-03909-2

• [tymanskyj-2018-axon-morphogenesis-abstract]: Tymanskyj SR, Yang BH, Verhey KJ, Ma L. (2018) MAP7 regulates axon morphogenesis by recruiting kinesin-1 to microtubules and modulating organelle transport. eLife. 7:e36374. PMID: 30132755. DOI: 10.7554/eLife.36374

• [tymanskyj-2019-branch-retraction-abstract]: Tymanskyj SR, Ma L. (2019) MAP7 Prevents Axonal Branch Retraction by Creating a Stable Microtubule Boundary to Rescue Polymerization. J Neurosci. 39(36):7118-7131. PMID: 31391261. DOI: 10.1523/JNEUROSCI.0775-19.2019

• [hooikaas-2019-map7-family-abstract]: Hooikaas PJ, Martin M, Muhlethaler T, et al. (2019) MAP7 family proteins regulate kinesin-1 recruitment and activation. J Cell Biol. 218(4):1298-1318. PMID: 30770434. DOI: 10.1083/jcb.201808065

• [chaudhary-2019-organelle-transport-abstract]: Chaudhary AR, Lu H, Krementsova EB, Bookwalter CS, Trybus KM, Hendricks AG. (2019) MAP7 regulates organelle transport by recruiting kinesin-1 to microtubules. J Biol Chem. 294(26):10160-10171. PMID: 31085585. DOI: 10.1074/jbc.RA119.008052

• [ferro-2022-kinesin-structure-abstract]: Ferro LS, Fang Q, Eshun-Wilson L, et al. (2022) Structural and functional insight into regulation of kinesin-1 by microtubule-associated protein MAP7. Science. 375(6578):268-272. PMID: 35050657. DOI: 10.1126/science.abf6154

• [adler-2024-mtbd-structure-abstract]: Adler A, Bangera M, Beugelink JW, Bahri S, van Ingen H, Moores CA, Baldus M. (2024) A structural and dynamic visualization of the interaction between MAP7 and microtubules. Nat Commun. 15(1):1574. PMID: 38431715. DOI: 10.1038/s41467-024-46260-5

• [komada-2000-spermatogenesis-abstract]: Komada M, McLean DJ, Griswold MD, Russell LD, Soriano P. (2000) E-MAP-115, encoding a microtubule-associated protein, is a retinoic acid-inducible gene required for spermatogenesis. Genes Dev. 14(11):1332-42. DOI: 10.1101/gad.14.11.1332

• [kikuchi-2018-wnt-signaling-abstract]: Kikuchi K, Nakamura A, Arata M, Shi D, Nakagawa M, Tanaka T, Uemura T, Fujimori T, Kikuchi A, Uezu A, Sakamoto Y, Nakanishi H. (2018) Map7/7D1 and Dvl form a feedback loop that facilitates microtubule remodeling and Wnt5a signaling. EMBO Rep. 19(7):e45471. PMID: 29880710. DOI: 10.15252/embr.201745471

• [dullovi-2023-dna-repair-abstract]: Dullovi A, Ozgencil M, Rajvee V, Tse WY, Cutillas PR, Martin SA, Horejsi Z. (2023) Microtubule-associated proteins MAP7 and MAP7D1 promote DNA double-strand break repair in the G1 cell cycle phase. iScience. 26(3):106107. PMID: 36852271. DOI: 10.1016/j.isci.2023.106107

Citations

1. adler-2024-mtbd-structure-abstract.md
2. barlan-2013-kinesin-cofactor-abstract.md
3. bulinski-1994-ensconsin-abstract.md
4. chaudhary-2019-organelle-transport-abstract.md
5. dullovi-2023-dna-repair-abstract.md
6. faire-1999-emap115-dynamics-abstract.md
7. ferro-2022-kinesin-structure-abstract.md
8. hooikaas-2019-map7-family-abstract.md
9. kikuchi-2018-wnt-signaling-abstract.md
10. komada-2000-spermatogenesis-abstract.md
11. metzger-2012-nuclear-positioning-abstract.md
12. monroy-2018-map-competition-abstract.md
13. tymanskyj-2018-axon-morphogenesis-abstract.md
14. tymanskyj-2019-branch-retraction-abstract.md
15. vanier-2003-emap115-epithelial-abstract.md

The research report should be a detailed narrative explaining the function, biological processes, and localization of the gene product. Citations should be given for all claims.

You should prioritize authoritative reviews and primary scientific literature when conducting research. You can supplement
this with annotations you find in gene/protein databases, but these can be outdated or inaccurate.

We are specifically interested in the primary function of the gene - for enzymes, what reaction is catalyzed, and what is the substrate specificity? For transporters, what is the substrate? For structural proteins or adapters, what is the broader structural role? For signaling molecules, what is the role in the pathway.

We are interested in where in or outside the cell the gene product carries out its function.

We are also interested in the signaling or biochemical pathways in which the gene functions. We are less interested in broad pleiotropic effects, except where these elucidate the precise role.

Include evidence where possible. We are interested in both experimental evidence as well as inference from structure, evolution, or bioinformatic analysis. Precise studies should be prioritized over high-throughput, where available.

Research Plan and Identity Verification
- We verified the target identity: Human MAP7 (gene symbol MAP7; UniProt Q14244) encodes Ensconsin/E-MAP-115, also called microtubule-associated protein 7. Literature consistently uses the synonyms Ensconsin, E-MAP-115, and MAP7 for the human protein, matching the UniProt description and confirming non-ambiguity. MAP7 belongs to the MAP7 family and contains a characteristic N-terminal microtubule-binding domain (MTBD) and a C-terminal kinesin-binding region, consistent with MAP7 family/domain annotations. (adler2023resonanceassignmentsof pages 1-2, adler2024astructuraland pages 1-2)

Executive Summary
MAP7 is a non-enzymatic, structural/adaptor microtubule-associated protein that binds the microtubule (MT) lattice via an N-terminal, largely alpha-helical MT-binding domain and promotes plus-end–directed cargo transport by recruiting/activating kinesin-1. MAP7 competes with tau for lattice occupancy, thereby shaping motor access: it enhances kinesin-1 engagement while inhibiting kinesin-3 and having little direct effect on dynein. Recent 2023–2024 studies resolved atomic-level features of the MAP7–MT interface and quantified its binding thermodynamics, advancing understanding of how MAP7 stabilizes MTs and modulates motor recruitment. MAP7 also acts in epithelial polarity and Wnt5a–Dishevelled signaling by positioning Dvl and MT plus ends at the cortex through a kinesin-1–dependent mechanism. Dysregulated MAP7 has been linked to several cancer contexts. (adler2024astructuraland pages 1-2, adler2023resonanceassignmentsof pages 1-2, monroy2018competitionbetweenmicrotubuleassociated pages 1-2, monroy2018competitionbetweenmicrotubuleassociated pages 3-4, kikuchi2018map77d1anddvl pages 1-2, adler2024astructuraland pages 13-14)

Key concepts and definitions
- Protein and domains: MAP7 (Ensconsin/E-MAP-115) is a human microtubule-associated protein with an N-terminal MTBD of ~112 residues (approx. 59–170) that is predominantly alpha-helical with a short hinge, and a C-terminal region that binds kinesin-1. This architecture underlies dual functions in MT binding/stabilization and kinesin-1 recruitment. Publication: Adler et al., Biomolecular NMR Assignments, April 2023; URL: https://doi.org/10.1007/s12104-023-10124-8. Publication: Adler et al., Nature Communications, March 2024; URL: https://doi.org/10.1038/s41467-024-46260-5. (adler2023resonanceassignmentsof pages 1-2, adler2024astructuraland pages 1-2)
- Primary molecular role: MAP7 is a structural regulator/adaptor on MTs that both stabilizes/bundles MTs and recruits/activates kinesin-1 to the lattice to promote plus-end–directed transport. It is not an enzyme or transporter; instead, it modulates cytoskeletal dynamics and motor access. Publication: Monroy et al., Nature Communications, August 2018; URL: https://doi.org/10.1038/s41467-018-03909-2. (monroy2018competitionbetweenmicrotubuleassociated pages 1-2)
- Motor-class specificity: MAP7 promotes kinesin-1 recruitment/landing and can inhibit kinesin-3 while having minimal direct effect on cytoplasmic dynein, defining a MAP-based code that biases motor traffic. Publication: Monroy et al., Nature Communications, August 2018; URL: https://doi.org/10.1038/s41467-018-03909-2. (monroy2018competitionbetweenmicrotubuleassociated pages 1-2, monroy2018competitionbetweenmicrotubuleassociated pages 3-4)

Recent developments and latest research (priority to 2023–2024)
- Atomic-level interface on MTs: A 2024 structural study combined solution/solid-state NMR, electron microscopy, fluorescence anisotropy, and isothermal titration calorimetry to map how the MTBD engages the MT lattice. The MTBD is a long alpha-helix with a short hinge and binds across more than one tubulin dimer, with contributions from the negatively charged tubulin C-terminal tails. ITC reported KD ~0.94 µM for MAP7 MTBD with MTs and ~0.5 stoichiometry per tubulin tetramer context, supporting tight but reversible binding. Publication: Adler et al., Nature Communications, March 2024; URL: https://doi.org/10.1038/s41467-024-46260-5. (adler2024astructuraland pages 1-2, adler2024astructuraland pages 13-14)
- NMR assignments of MTBD in solution: Preceding the 2024 work, a 2023 NMR assignment paper showed the isolated MTBD is primarily alpha-helical with a central helix interrupted by a flexible four-residue hinge—informing subsequent structural interpretation on lattices. Publication: Adler et al., Biomolecular NMR Assignments, April 2023; URL: https://doi.org/10.1007/s12104-023-10124-8. (adler2023resonanceassignmentsof pages 1-2)
- Mechanistic impact on motor recruitment: Foundational single-molecule transport work quantified that MAP7 increases kinesin-1 landing rates by ~15-fold and decreases Km for MTs (KmMT from ~1.46 ± 0.21 µM to ~0.27 ± 0.04 µM for K560), modestly slowing velocity and slightly increasing processivity—consistent with a role in recruiting and tuning motor engagement. Publication: Monroy et al., Nature Communications, August 2018; URL: https://doi.org/10.1038/s41467-018-03909-2. (monroy2018competitionbetweenmicrotubuleassociated pages 3-4)
- MAP competition on the lattice: MAP7 displaces tau from MTs owing to higher affinity and longer dwell times (KD ~0.46 µM for MAP7 vs ~1.56 µM for tau; dwell ~82 s vs ~1.9 s), revealing how MAP7 can locally reprogram motor access by remodeling MAP occupancy. Publication: Monroy et al., Nature Communications, August 2018; URL: https://doi.org/10.1038/s41467-018-03909-2. (monroy2018competitionbetweenmicrotubuleassociated pages 1-2)

Subcellular localization and cellular processes
- Localization: MAP7 decorates the MT lattice in diverse cells, including neurons and epithelia; in response to Wnt5a signaling, MAP7/MAP7D1–kinesin-1 complexes traffic toward MT plus ends and enrich Dishevelled (Dvl) at the cortex, supporting polarized epithelial organization. Publication: Kikuchi et al., EMBO Reports, June 2018; URL: https://doi.org/10.15252/embr.201745471. (kikuchi2018map77d1anddvl pages 1-2)
- Neuronal roles: Through tau competition and strong promotion of kinesin-1 microtubule engagement, MAP7 biases axonal transport toward kinesin-driven movement and has been implicated in axonal branching phenotypes when overexpressed. Publication: Monroy et al., Nature Communications, August 2018; URL: https://doi.org/10.1038/s41467-018-03909-2. (monroy2018competitionbetweenmicrotubuleassociated pages 3-4)
- Mitosis and spindle function: Structural and biophysical work notes roles for MAP7 family members in MT stabilization and spindle organization; 2024 structural data add mechanistic clarity to how the MTBD stabilizes the lattice through multi-dimer interactions and C-terminal tail contacts—features relevant to spindle microtubule stability. Publication: Adler et al., Nature Communications, March 2024; URL: https://doi.org/10.1038/s41467-024-46260-5. (adler2024astructuraland pages 1-2)
- Epithelial polarity and Wnt5a–Dvl pathway: MAP7/MAP7D1 bind Dvl, promote Dvl cortical localization, and facilitate plus-end targeting of MTs via KIF5B, forming a feedback loop where Wnt5a also drives MAP7/7D1 movement to plus ends; Dishevelled stabilizes MAP7/7D1 in turn. Publication: Kikuchi et al., EMBO Reports, June 2018; URL: https://doi.org/10.15252/embr.201745471. (kikuchi2018map77d1anddvl pages 1-2)

Structural basis of function and motor specificity
- MTBD conformation and binding site: The MTBD is predominantly alpha-helical with a hinge and binds across the lattice beyond a single heterodimer, leveraging interactions with tubulin C-terminal tails; multiple datasets (NMR, EM, cryo-EM maps and models) underpin this view in 2023–2024. Publication: Adler et al., Nature Communications, March 2024; URL: https://doi.org/10.1038/s41467-024-46260-5. Publication: Adler et al., Biomolecular NMR Assignments, April 2023; URL: https://doi.org/10.1007/s12104-023-10124-8. (adler2024astructuraland pages 1-2, adler2024astructuraland pages 13-14, adler2023resonanceassignmentsof pages 1-2)
- Kinesin-1 recruitment and tuning: Single-molecule assays demonstrate that MAP7 increases kinesin-1 landing rates ~15-fold and decreases KmMT, reduces velocity modestly, and increases processivity slightly; MAP7’s negatively charged C-terminus contributes to displacing tau, further favoring kinesin-1 access. Publication: Monroy et al., Nature Communications, August 2018; URL: https://doi.org/10.1038/s41467-018-03909-2. (monroy2018competitionbetweenmicrotubuleassociated pages 3-4, monroy2018competitionbetweenmicrotubuleassociated pages 1-2)
- Specificity across motor classes: In vitro reconstitution indicates that MAP7 promotes kinesin-1, inhibits kinesin-3, and has little effect on dynein, highlighting a MAP-based mechanism that partitions motor traffic. Publication: Monroy et al., Nature Communications, August 2018; URL: https://doi.org/10.1038/s41467-018-03909-2. (monroy2018competitionbetweenmicrotubuleassociated pages 1-2)

Current applications and real-world implementations
- Reconstitution and mechanistic measurements: MAP7 is used in in vitro reconstitution systems to tune kinesin-1 motility parameters and to model MAP competition with tau, informing transport biases in axons. Quantitative parameters (landing rate increases, KD values, dwell times) enable model calibration for intracellular transport. Publication: Monroy et al., Nature Communications, August 2018; URL: https://doi.org/10.1038/s41467-018-03909-2. Publication: Adler et al., Nature Communications, March 2024; URL: https://doi.org/10.1038/s41467-024-46260-5. (monroy2018competitionbetweenmicrotubuleassociated pages 3-4, adler2024astructuraland pages 1-2)
- Structural datasets for design: Cryo-EM maps and NMR assignments deposited by 2023–2024 studies provide resources for computational modeling of MAP7–MT binding and for designing mutants that test motor recruitment hypotheses. Publication: Adler et al., Nature Communications, March 2024; URL: https://doi.org/10.1038/s41467-024-46260-5. (adler2024astructuraland pages 13-14)
- Cell polarity systems: In epithelial cell models, MAP7/7D1–KIF5B–Dvl modules are used to interrogate Wnt5a-driven planar polarity and cortical MT remodeling, offering a system-level handle on cytoskeletal signaling crosstalk. Publication: Kikuchi et al., EMBO Reports, June 2018; URL: https://doi.org/10.15252/embr.201745471. (kikuchi2018map77d1anddvl pages 1-2)

Expert opinions and analysis (authoritative sources)
- Structural biophysics view: The 2024 Nature Communications study emphasizes that MAP7’s interaction area extends beyond a single tubulin dimer and involves C-terminal tubulin tails, suggesting why MAP7 can stabilize the lattice and persist on MTs to shape motor access over long dwell times—consistent with a high-affinity, high-dwell MAP that reprograms lattice occupancy. Publication: Adler et al., Nature Communications, March 2024; URL: https://doi.org/10.1038/s41467-024-46260-5. (adler2024astructuraland pages 1-2)
- Transport regulation principle: The 2018 Nature Communications study frames a general principle that competition among non-motor MAPs (MAP7 vs tau) dictates access of motors to the MT lattice, thereby directing the balance of transport (kinesin-1 vs kinesin-3 vs dynein). Publication: Monroy et al., Nature Communications, August 2018; URL: https://doi.org/10.1038/s41467-018-03909-2. (monroy2018competitionbetweenmicrotubuleassociated pages 1-2)
- Cytoskeletal signaling integration: MAP7/7D1 engagement with Dvl and kinesin-1 places MAP7 at the intersection of cytoskeletal dynamics and Wnt signaling, linking cortical polarity to motor-driven MT plus-end targeting. Publication: Kikuchi et al., EMBO Reports, June 2018; URL: https://doi.org/10.15252/embr.201745471. (kikuchi2018map77d1anddvl pages 1-2)

Statistics and quantitative data from recent studies
- Binding and stoichiometry: MAP7 MTBD–MT binding KD ~0.94 µM (ITC) with a stoichiometry of ~0.5 per tubulin tetramer context; binding extends beyond a single tubulin dimer and involves tubulin C-terminal tails. Publication: Adler et al., Nature Communications, March 2024; URL: https://doi.org/10.1038/s41467-024-46260-5. (adler2024astructuraland pages 1-2)
- Motor recruitment metrics: MAP7 increases K560 (kinesin-1) landing rate ~15-fold; lowers KmMT (1.46 ± 0.21 µM to 0.27 ± 0.04 µM); slightly increases processivity (~874 to ~984 nm) and decreases velocity (~434 to ~328 nm/s). Publication: Monroy et al., Nature Communications, August 2018; URL: https://doi.org/10.1038/s41467-018-03909-2. (monroy2018competitionbetweenmicrotubuleassociated pages 3-4)
- MAP competition: Affinity and dwell-time differences vs tau (MAP7 KD ~0.46 µM; dwell ~82.3 s) explain effective displacement of tau (KD ~1.56 µM; dwell ~1.9 s), reprogramming the local lattice. Publication: Monroy et al., Nature Communications, August 2018; URL: https://doi.org/10.1038/s41467-018-03909-2. (monroy2018competitionbetweenmicrotubuleassociated pages 1-2)

Disease associations
- Cancer links: The 2024 structural study’s discussion collates reports of MAP7 upregulation and associations with disease phenotypes (e.g., progression or prognosis in certain cancers and drug-response modulation), underscoring active investigation into MAP7 as a biomarker or modulator of chemoresponse. Publication: Adler et al., Nature Communications, March 2024; URL: https://doi.org/10.1038/s41467-024-46260-5. (adler2024astructuraland pages 13-14)

Concise reference table
| Topic | Key findings | Evidence |
|---|---|---|
| Identity & synonyms | MAP7 corresponds to human Ensconsin / E‑MAP‑115 (gene MAP7; UniProt Q14244). | (adler2023resonanceassignmentsof pages 1-2, adler2024astructuraland pages 1-2) |
| Family / domains (MTBD 59–170; C-terminal kinesin-binding region) | MAP7 contains an N-terminal ~112 aa microtubule-binding domain (MTBD; residues ~59–170) and a C-terminal region that binds kinesin‑1. | (adler2023resonanceassignmentsof pages 1-2, adler2024astructuraland pages 1-2) |
| Primary functions (MT binding, stabilization/bundling; recruit/activate kinesin‑1) | Binds and stabilizes microtubules, can bundle MTs, and recruits/activates kinesin‑1 to the lattice to promote plus‑end directed cargo transport. | (monroy2018competitionbetweenmicrotubuleassociated pages 1-2, adler2023resonanceassignmentsof pages 1-2) |
| Motor specificity effects (kinesin‑1 promoted, kinesin‑3 inhibited, dynein unaffected) | MAP7 strongly promotes kinesin‑1 landing and activity, inhibits kinesin‑3, and shows little to no direct effect on cytoplasmic dynein. | (monroy2018competitionbetweenmicrotubuleassociated pages 1-2, monroy2018competitionbetweenmicrotubuleassociated pages 3-4) |
| Structural basis of MT binding (alpha‑helical MTBD; interactions beyond single dimer incl. tubulin C‑terminal tails; KD values) | The MTBD is primarily α‑helical (long helix with a short hinge); it contacts more than a single tubulin dimer and engages tubulin C‑terminal tails; measured KD in the sub‑ to low‑micromolar range (~0.5–1 µM depending on assay). | (adler2023resonanceassignmentsof pages 1-2, adler2024astructuraland pages 1-2) |
| Subcellular localization (MT lattice; axons/epithelial cortex; plus‑end targeting via KIF5B/Wnt5a) | Localizes to the microtubule lattice in many cell types, enriched in axons/regions of dynamic MTs and recruited to cortical/plus‑end regions in epithelial cells in a KIF5B (kinesin‑1)‑dependent, Wnt5a‑responsive manner. | (kikuchi2018map77d1anddvl pages 1-2, monroy2018competitionbetweenmicrotubuleassociated pages 1-2) |
| Roles in cellular processes (mitosis/spindle, neuronal transport/branching, epithelial polarity / Wnt5a‑Dvl) | Functions in mitotic spindle growth/orientation, supports kinesin‑1‑dependent neuronal cargo transport and axon/branch formation, and mediates cortical MT targeting and Disheveled (Dvl) localization in Wnt5a signaling for epithelial polarity. | (kikuchi2018map77d1anddvl pages 1-2, monroy2018competitionbetweenmicrotubuleassociated pages 1-2) |
| Recent 2023–2024 advances | Atomic‑level and NMR/cro��‑EM characterization of the MAP7 MTBD resolved its helical binding mode on MTs and quantified biophysical parameters of MT engagement and motor recruitment (2023–2024). | (adler2024astructuraland pages 1-2, adler2023resonanceassignmentsof pages 1-2) |
| Disease associations (cancer expression/prognosis; cancer signatures) | Altered MAP7 expression has been reported in multiple cancer contexts and linked to prognostic signatures and altered drug responses; mechanistic/disease links remain under active study. | (adler2024astructuraland pages 13-14) |

Table: A compact reference table summarizing MAP7 identity, domains, primary functions, motor specificity, structural basis, localization, cellular roles, recent structural advances (2023–2024), and disease associations with citations to source excerpts.

Limitations and open questions
- While structural insights into the MTBD (2023–2024) are strong, higher-resolution mapping of the kinesin-1–interacting C-terminal region on the motor and its dynamics on the lattice in human systems remains a priority. How MAP7 integration with other MAPs (beyond tau) and PTM codes regulates selectivity for different kinesins in vivo is an active area of research. (adler2024astructuraland pages 1-2, monroy2018competitionbetweenmicrotubuleassociated pages 1-2)

References (with URLs and publication dates)
- Adler A, Bangera M, Beugelink JW, Bahri S, van Ingen H, Moores CA, Baldus M. A structural and dynamic visualization of the interaction between MAP7 and microtubules. Nature Communications. March 2024. URL: https://doi.org/10.1038/s41467-024-46260-5 (adler2024astructuraland pages 1-2, adler2024astructuraland pages 13-14)
- Adler A, Kjaer LF, Beugelink JW, Baldus M, van Ingen H. Resonance assignments of the microtubule-binding domain of the microtubule-associated protein 7 (MAP7). Biomolecular NMR Assignments. April 2023. URL: https://doi.org/10.1007/s12104-023-10124-8 (adler2023resonanceassignmentsof pages 1-2)
- Monroy BY, Sawyer DL, Ackermann BE, Borden MM, Tan TC, Ori-McKenney KM. Competition between microtubule-associated proteins directs motor transport. Nature Communications. August 2018. URL: https://doi.org/10.1038/s41467-018-03909-2 (monroy2018competitionbetweenmicrotubuleassociated pages 1-2, monroy2018competitionbetweenmicrotubuleassociated pages 3-4)
- Kikuchi K, Nakamura A, Arata M, et al. Map7/7D1 and Dvl form a feedback loop that facilitates microtubule remodeling and Wnt5a signaling. EMBO Reports. June 2018. URL: https://doi.org/10.15252/embr.201745471 (kikuchi2018map77d1anddvl pages 1-2)

Conclusion
Human MAP7 (Ensconsin/E-MAP-115) is a MAP7-family, MAP7-domain protein whose N-terminal alpha-helical MTBD binds and stabilizes the microtubule lattice and whose C-terminus recruits/tunes kinesin-1. By competing with tau and biasing motor access, MAP7 enhances kinesin-1 transport while inhibiting kinesin-3 and sparing dynein. Recent 2023–2024 structural biophysics established the MTBD’s helical lattice-binding mode and quantified MAP7–MT thermodynamics, refining mechanistic models of transport regulation, spindle stability, and epithelial polarity signaling. Disease links, especially in cancer, are emerging from expression/prognostic observations and merit further mechanistic study. (adler2024astructuraland pages 1-2, adler2023resonanceassignmentsof pages 1-2, monroy2018competitionbetweenmicrotubuleassociated pages 1-2, monroy2018competitionbetweenmicrotubuleassociated pages 3-4, kikuchi2018map77d1anddvl pages 1-2, adler2024astructuraland pages 13-14)

References

1. (adler2023resonanceassignmentsof pages 1-2): Agnes Adler, Lenette F. Kjaer, J. Wouter Beugelink, Marc Baldus, and Hugo van Ingen. Resonance assignments of the microtubule-binding domain of the microtubule-associated protein 7 (map7). Biomolecular Nmr Assignments, 17:83-88, Apr 2023. URL: https://doi.org/10.1007/s12104-023-10124-8, doi:10.1007/s12104-023-10124-8. This article has 3 citations and is from a peer-reviewed journal.

2. (adler2024astructuraland pages 1-2): Agnes Adler, Mamata Bangera, J. Wouter Beugelink, Salima Bahri, Hugo van Ingen, Carolyn A. Moores, and Marc Baldus. A structural and dynamic visualization of the interaction between map7 and microtubules. Nature Communications, Mar 2024. URL: https://doi.org/10.1038/s41467-024-46260-5, doi:10.1038/s41467-024-46260-5. This article has 10 citations and is from a highest quality peer-reviewed journal.

3. (monroy2018competitionbetweenmicrotubuleassociated pages 1-2): Brigette Y. Monroy, Danielle L. Sawyer, Bryce E. Ackermann, Melissa M. Borden, Tracy C. Tan, and Kassandra M. Ori-McKenney. Competition between microtubule-associated proteins directs motor transport. Nature Communications, Aug 2018. URL: https://doi.org/10.1038/s41467-018-03909-2, doi:10.1038/s41467-018-03909-2. This article has 247 citations and is from a highest quality peer-reviewed journal.

4. (monroy2018competitionbetweenmicrotubuleassociated pages 3-4): Brigette Y. Monroy, Danielle L. Sawyer, Bryce E. Ackermann, Melissa M. Borden, Tracy C. Tan, and Kassandra M. Ori-McKenney. Competition between microtubule-associated proteins directs motor transport. Nature Communications, Aug 2018. URL: https://doi.org/10.1038/s41467-018-03909-2, doi:10.1038/s41467-018-03909-2. This article has 247 citations and is from a highest quality peer-reviewed journal.

5. (kikuchi2018map77d1anddvl pages 1-2): Koji Kikuchi, Akira Nakamura, Masaki Arata, Dongbo Shi, Mami Nakagawa, Tsubasa Tanaka, Tadashi Uemura, Toshihiko Fujimori, Akira Kikuchi, Akiyoshi Uezu, Yasuhisa Sakamoto, and Hiroyuki Nakanishi. Map7/7d1 and dvl form a feedback loop that facilitates microtubule remodeling and wnt5a signaling. EMBO reports, Jun 2018. URL: https://doi.org/10.15252/embr.201745471, doi:10.15252/embr.201745471. This article has 29 citations and is from a highest quality peer-reviewed journal.

6. (adler2024astructuraland pages 13-14): Agnes Adler, Mamata Bangera, J. Wouter Beugelink, Salima Bahri, Hugo van Ingen, Carolyn A. Moores, and Marc Baldus. A structural and dynamic visualization of the interaction between map7 and microtubules. Nature Communications, Mar 2024. URL: https://doi.org/10.1038/s41467-024-46260-5, doi:10.1038/s41467-024-46260-5. This article has 10 citations and is from a highest quality peer-reviewed journal.

Citations

1. monroy2018competitionbetweenmicrotubuleassociated pages 1-2
2. adler2023resonanceassignmentsof pages 1-2
3. monroy2018competitionbetweenmicrotubuleassociated pages 3-4
4. adler2024astructuraland pages 1-2
5. adler2024astructuraland pages 13-14
6. https://doi.org/10.1007/s12104-023-10124-8.
7. https://doi.org/10.1038/s41467-024-46260-5.
8. https://doi.org/10.1038/s41467-018-03909-2.
9. https://doi.org/10.15252/embr.201745471.
10. https://doi.org/10.1038/s41467-024-46260-5
11. https://doi.org/10.1007/s12104-023-10124-8
12. https://doi.org/10.1038/s41467-018-03909-2
13. https://doi.org/10.15252/embr.201745471
14. https://doi.org/10.1007/s12104-023-10124-8,
15. https://doi.org/10.1038/s41467-024-46260-5,
16. https://doi.org/10.1038/s41467-018-03909-2,
17. https://doi.org/10.15252/embr.201745471,

Ensconsin (MAP7): Microtubule-Associated Protein 7 in Human

Identification and Overview

MAP7 (Microtubule-Associated Protein 7), also known as Ensconsin or E-MAP-115 (epithelial MAP of 115 kDa), is a human microtubule-binding protein predominantly expressed in epithelial cells (pubmed.ncbi.nlm.nih.gov). It was first identified in the early 1990s by Masson and Kreis (1993) in HeLa cells as a novel protein tightly associated with microtubules (pmc.ncbi.nlm.nih.gov) (pubmed.ncbi.nlm.nih.gov). Unlike other MAPs of similar size, MAP7’s binding to microtubules is “nucleotide-insensitive,” meaning it remains attached regardless of the tubulin’s nucleotide state (pubmed.ncbi.nlm.nih.gov). The name Ensconsin (from “ensconce,” to secure firmly) reflects its tenacious microtubule association (pmc.ncbi.nlm.nih.gov). Human MAP7 is ~750 amino acids in length (~115 kDa) and is the founding member of the MAP7 family (with paralogs MAP7D1, MAP7D2, MAP7D3 in mammals). It plays a multifaceted role in organizing the microtubule cytoskeleton and linking it to intracellular transport processes (pmc.ncbi.nlm.nih.gov).

Basic Function: MAP7 is principally a microtubule-stabilizing protein that binds directly to microtubule filaments and modulates their dynamics (pubmed.ncbi.nlm.nih.gov). Early studies showed that overexpression of MAP7’s N-terminal domain in cells could render microtubules resistant to the depolymerizing drug nocodazole, demonstrating its potent stabilizing effect (pubmed.ncbi.nlm.nih.gov). In epithelial cells (such as Caco-2 and MDCK), MAP7 expression increases as cells polarize and differentiate, suggesting it is important for organizing stable microtubule arrays during the establishment of cell polarity (pubmed.ncbi.nlm.nih.gov) (pubmed.ncbi.nlm.nih.gov). Consistently, MAP7 is abundant in highly differentiated, polarized epithelial cells (e.g. intestinal absorptive cells, kidney tubule cells), and its levels correlate with the degree of apicobasal polarity (pubmed.ncbi.nlm.nih.gov). In developing mouse tissues, Map7 (E-MAP-115) is expressed from mid-embryogenesis onward in many epithelia and some neurons, peaking as cells mature and polarize (pubmed.ncbi.nlm.nih.gov) (pubmed.ncbi.nlm.nih.gov). These patterns suggest a fundamental role for MAP7 in organizing microtubules to support specialized cell architecture and intracellular organization. Indeed, the unique in vivo distribution of MAP7 led researchers to propose it is crucial for microtubule reorganization during epithelial differentiation and polarization (pubmed.ncbi.nlm.nih.gov).

Structural Features and Localization

Domain Architecture: MAP7 contains an N-terminal microtubule-binding domain (MTBD) and a C-terminal region implicated in binding motor proteins. The MT-binding domain is roughly 100–120 amino acids long (residues ~59–170) and is highly conserved (www.nature.com). Structural studies (NMR and cryo-EM in 2023-2024) reveal that this MTBD forms a long α-helix with a short hinge and binds along the microtubule lattice, engaging multiple tubulin subunits including tubulin C-terminal tails (www.nature.com) (www.nature.com). This extended binding interface underpins MAP7’s strong attachment and its ability to stabilize microtubules: the MTBD can “lock” onto protofilaments and even promote tubulin polymerization under conditions where microtubules would not normally form (www.nature.com) (www.nature.com). Notably, adding the purified MAP7 MTBD to tubulin in vitro induces microtubule assembly and bundling, indicating that this domain alone is sufficient to nucleate and stabilize microtubules (www.nature.com). Beyond the MTBD, MAP7’s C-terminal region is largely coiled-coil and contains a kinesin-1 interaction domain (as shown by co-immunoprecipitation and truncation analyses (pmc.ncbi.nlm.nih.gov)). This allows MAP7 to serve as a scaffold, binding microtubules via its N-terminus and motor proteins via its C-terminus, effectively linking microtubule tracks to motors.

Subcellular Localization: Under interphase conditions, MAP7 decorates the microtubule lattice, particularly on more stable microtubule subsets. In cultured cells like HeLa, E-MAP-115 was observed to associate preferentially with perinuclear microtubules (pubmed.ncbi.nlm.nih.gov) – the region around the centrosome/Golgi where microtubules are often long-lived and post-translationally modified. Recent imaging in human bronchial epithelial cells (BEAS-2B) similarly found MAP7 enriched on perinuclear microtubules, whereas another MAP (MAP4) uniformly coated all microtubules (pmc.ncbi.nlm.nih.gov). Intriguingly, MAP7 colocalizes strongly with acetylated tubulin – a hallmark of stable, long-lived microtubules (pmc.ncbi.nlm.nih.gov). This supports that MAP7 associates dynamically with the subset of microtubules that are stabilized and involved in maintaining cell structure. In polarized epithelial monolayers (e.g. Caco-2 forming domes/blisters), MAP7 levels and microtubule binding increase as the cells establish apical junctions (pubmed.ncbi.nlm.nih.gov), hinting that MAP7 may help anchor microtubules to these specialized structures (possibly facilitating intercellular contact formation (www.genecards.org)).

During cell division, MAP7’s localization is tightly regulated. It is largely absent from microtubules in early prophase, when many MAPs are released (pmc.ncbi.nlm.nih.gov). However, as cells progress to metaphase, MAP7 becomes concentrated at the spindle poles and then spreads to coat the mitotic spindle microtubules (pmc.ncbi.nlm.nih.gov). By telophase, it decorates the spindle midzone. This dynamic redistribution is controlled by phosphorylation: MAP7 is hyper-phosphorylated in mitotic cells, which transiently reduces its microtubule binding affinity (pmc.ncbi.nlm.nih.gov). Indeed, in mitotic extracts, hyper-phosphorylated MAP7 remains in the supernatant (unbound) unless dephosphorylated (pmc.ncbi.nlm.nih.gov). As specific cell-cycle kinases become active or inactive, MAP7 gets dephosphorylated at spindle poles and re-binds microtubules later in mitosis (pmc.ncbi.nlm.nih.gov). This regulated binding ensures that MAP7 engages the spindle at the correct time, potentially to assist in spindle stabilization and chromosome segregation. In support of that role, experiments in Drosophila neural stem cells showed that Ensconsin/MAP7 promotes robust spindle microtubule growth and proper centrosome separation during mitosis (pmc.ncbi.nlm.nih.gov). Thus, MAP7’s localization is dynamic – cytoskeletal association is controlled spatially and temporally by signaling events, allowing MAP7 to function where and when it’s needed.

Regulation: Multiple kinases regulate MAP7. For example, the MARK/Par-1 kinase phosphorylates MAP7 at several serine sites (including Ser168 and Ser198, conserved in mammals) (pmc.ncbi.nlm.nih.gov). In Drosophila oocytes, Par-1-dependent phosphorylation restricts MAP7’s localization to the anterior of the oocyte, helping establish cell polarity (pmc.ncbi.nlm.nih.gov). Mutating those phosphorylation sites causes MAP7 to mis-localize (no longer anteriorly confined), although its basic microtubule-binding ability remains intact (pmc.ncbi.nlm.nih.gov). This indicates phosphorylation primarily modulates MAP7’s distribution rather than turning binding on/off. In summary, MAP7 is a cytosolic protein associating with microtubule networks (and in rare contexts it can appear in the nucleus – see below), with its localization fine-tuned by post-translational modifications and possibly protein partners.

Role in Microtubule Stabilization and Dynamics

MAP7’s foremost function is to stabilize and organize microtubules. As a lattice-binding protein, it can suppress microtubule dynamic instability and promote polymerization. The original characterization concluded MAP7 “is a microtubule-stabilizing protein” (pubmed.ncbi.nlm.nih.gov): cells engineered to overexpress MAP7’s MT-binding fragment maintained microtubules even after nocodazole exposure, a clear sign that MAP7 can protect microtubules from disassembly (pubmed.ncbi.nlm.nih.gov). Mechanistically, MAP7 binds along the tubulin protofilaments and can “bridge” adjacent tubulin dimers, which likely reinforces lateral and longitudinal tubulin contacts (www.nature.com) (www.nature.com). Cryo-EM studies (Nature Communications, 2024) have visualized how the MAP7 MTBD lies in the microtubule inner groove and interacts with tubulin tails, effectively locking the lattice in a polymerized state (www.nature.com) (www.nature.com). This structural stabilization is so robust that adding the MAP7 MTBD can induce microtubule assembly at tubulin concentrations normally too low for polymerization (www.nature.com). Furthermore, at high MAP7:tubulin ratios, it causes formation of unusually thick polymers (possibly multiple microtubule protofilament sheets) (www.nature.com), underscoring its potent polymerization effect.

Consistent with these biochemical effects, MAP7 is associated with stable microtubule populations in cells. Many of these microtubules carry specific tubulin post-translational modifications (PTMs) linked to stability, notably acetylation and detyrosination. A recent Developmental Cell study (Shen & Ori-McKenney, 2024) revealed that MAP7 actively promotes tubulin acetylation and concurrently prevents tubulin detyrosination, thereby sculpting the “tubulin code” on microtubules (pmc.ncbi.nlm.nih.gov). MAP7 binding allosterically makes the microtubule lattice a better substrate for αTAT1 (α-tubulin acetyltransferase), increasing α-tubulin Lys40 acetylation, and sterically hinders the enzyme vasohibin/SVBP that would normally remove the C-terminal tyrosine from tubulin (pmc.ncbi.nlm.nih.gov). Through these actions, MAP7 ensures microtubules bear modifications that correlate with stability and longevity. Under hyperosmotic stress (which causes cytoplasm to become crowded), cells sharply increase MAP7 association on microtubules and raise acetylation levels ~3-4 fold, presumably to stabilize the network in the face of stress (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov). If MAP7 is depleted, acetylation levels drop and microtubules instead become more detyrosinated (a state that can indicate older microtubules but in this context was linked to instability) (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov). These findings identify MAP7 as a key factor that remodels the microtubule cytoskeleton in response to cellular conditions, enhancing stability when needed for adaptation (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov).

Biologically, stabilizing select microtubule subsets is crucial in processes like cell polarization, differentiation, and migration. MAP7 appears to fulfill this role in epithelial tissues: as noted, its expression and localization correlate with cells transitioning to a polarized, differentiated state (pubmed.ncbi.nlm.nih.gov). For example, in developing kidney and intestinal epithelia, cells start expressing high MAP7 only when they mature and form organized structures, and cells that lose polarity (like maturing podocytes) no longer express MAP7 (pubmed.ncbi.nlm.nih.gov) (pubmed.ncbi.nlm.nih.gov). This suggests MAP7 helps build the stable microtubule tracks required for transporting proteins and organelles to specific domains (apical vs basolateral) during differentiation. It may also participate in strengthening cell–cell junctions: one report indicates MAP7 co-localizes with the TRPV4 channel at the cell cortex and may help recruit TRPV4 to the membrane (www.genecards.org), hinting at a role in linking microtubules to membrane complexes. Additionally, during neuronal development, MAP7’s stabilizing influence is linked to axon outgrowth. Neurons often extend long, stable microtubule bundles in axons, and MAP7 is upregulated during the formation of axonal branches. In dorsal root ganglion neurons, increased MAP7 expression precedes collateral branch formation, and experimentally overexpressing MAP7 leads to a significant increase in the number of axon branches formed (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov). This indicates MAP7-mediated microtubule stabilization can drive the structural changes needed for new neurite outgrowth. Conversely, loss of MAP7 (or its close homologs) in neurons results in fewer branches or stunted axons (pmc.ncbi.nlm.nih.gov). Overall, by stabilizing microtubule arrays, MAP7 provides a structural scaffold essential for cell polarity, differentiation, and morphological plasticity.

Interactions with Motor Proteins and Transport

One of MAP7’s most unique functions is serving as an adapter between microtubules and motor proteins, particularly kinesin motors. MAP7 has been shown to bind the kinesin-1 family (KIF5) via its C-terminal domain, and in doing so, it can recruit and activate kinesin on microtubule tracks (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov). In Drosophila, Ensconsin (MAP7) is an essential co-factor for kinesin-1: it was discovered that certain cargos in oocytes and muscle cells only moved properly when Ensconsin was present to link kinesin to microtubules (pmc.ncbi.nlm.nih.gov). Sung et al. (2008) demonstrated that in fly oocytes, MAP7 is required for proper localization of determinants, acting via kinesin-1; and Metzger et al. (2012) found that in muscle cells, loss of Ensconsin or Kif5 disrupts nuclear positioning, leading to mispositioned myonuclei (pmc.ncbi.nlm.nih.gov) (www.nature.com). Similarly, a study in mammalian muscle cell cultures showed that MAP7 and KIF5B together are needed for moving nuclei to the correct positions during myotube formation (www.nature.com). Mutations in either MAP7 or kinesin heavy chain can lead to nuclei clustering abnormally, causing muscle fiber defects (www.nature.com). These findings highlight that MAP7 is a critical scaffolding factor for kinesin-1-driven transport in vivo.

At the cellular level, MAP7’s presence on microtubules biases organelle traffic toward the microtubule plus-ends (the typical direction of kinesin-1). A 2019 biochemical study (J. Biol. Chem.) reconstituted organelle transport with and without MAP7. In the absence of MAP7, isolated endosomal vesicles (phagosomes) exhibited roughly equal movement toward microtubule plus-ends and minus-ends (i.e., balanced activity of kinesin vs dynein motors). Strikingly, when MAP7 was present on microtubules, ~80% of vesicle movements became plus-end directed, compared to ~50% in controls (pubmed.ncbi.nlm.nih.gov) (pubmed.ncbi.nlm.nih.gov). This indicates that MAP7 can switch transport to a kinesin-dominant mode, favoring outgoing (anterograde) traffic (pubmed.ncbi.nlm.nih.gov). MAP7 achieves this not by increasing the power of individual kinesin motors, but by increasing their attachment frequency to microtubules (pubmed.ncbi.nlm.nih.gov). Single-molecule assays showed MAP7 does not change a single kinesin-1’s speed or force output, but it increases the likelihood that a kinesin will bind and stay bound to the microtubule track (pubmed.ncbi.nlm.nih.gov). In practice, this means more kinesin motors can engage simultaneously on a cargo. For cargos with multiple motors, MAP7 led to a greater number of kinesins teaming up, which in turn generated higher collective forces and more persistent plus-end movement (pubmed.ncbi.nlm.nih.gov). Thus, MAP7 acts as a molecular tether or loading factor that improves kinesin-1 access to microtubules, biasing transport toward the cell periphery (pubmed.ncbi.nlm.nih.gov) (pubmed.ncbi.nlm.nih.gov).

Conversely, MAP7 can exclude or compete with other microtubule-associated proteins, thereby modulating which motors can operate. Notably, MAP7 competes with Tau, the neuronal MAP, for binding sites on the microtubule lattice (pmc.ncbi.nlm.nih.gov). Tau is known to impede kinesin binding when abundant, so MAP7’s ability to displace Tau may relieve this inhibition and favor kinesin-1 attachment (pmc.ncbi.nlm.nih.gov). Additionally, MAP7 blocks kinesin-3 (KIF1 family) motility on microtubules (pmc.ncbi.nlm.nih.gov). Kinesin-3 motors typically carry different cargo (synaptic vesicles, etc.), so MAP7’s presence might prioritize kinesin-1 driven transport (e.g., of organelles) at the expense of kinesin-3 cargo if both compete for the same microtubule track (pmc.ncbi.nlm.nih.gov). This selective promotion of kinesin-1 is significant in contexts like axon development: kinesin-1 transports mitochondria and bulk cargo into axons, whereas kinesin-3 moves synaptic components. A 2018 study (Monroy et al., Nat. Commun.) showed that MAP7 and Tau have antagonistic effects on motor traffic – and indeed they found that MAP7 binding enhances kinesin-1 run length while preventing kinesin-3 from even accessing the microtubule (pmc.ncbi.nlm.nih.gov). Such competitive interactions suggest that cell types or regions with high MAP7 (e.g., proximal axon or soma) will favor large-scale organelle transport by kinesin-1, whereas distal regions with Tau might favor other dynamics. In summary, MAP7 orchestrates motor transport by acting as a platform that recruits kinesin-1 and by organizing the microtubule surface to exclude competing MAPs/motors. Through this, it profoundly influences intracellular trafficking and organelle distribution.

Physiological impacts: The MAP7–kinesin interaction underlies several key processes. In neurons, Chen et al. (eLife 2018) demonstrated that MAP7 is required for axon morphogenesis: by recruiting kinesin-1 to microtubules, MAP7 ensures proper distribution of organelles into growing axons and facilitates axon branch formation (pmc.ncbi.nlm.nih.gov) (www.nature.com). Without MAP7, developing neurons have transport defects that lead to shorter axons and fewer branches, linking the molecular interaction to neurodevelopment. In muscle cells, as mentioned, MAP7-mediated recruitment of kinesin is required to move nuclei along microtubules to evenly space them in muscle fibers (pmc.ncbi.nlm.nih.gov). Furthermore, in Drosophila S2 cells (a model for non-polarized cells), MAP7 was shown to help distribute organelles properly, again via kinesin-1 (pmc.ncbi.nlm.nih.gov). These diverse examples (neurons, muscle, oocytes, epithelial cells) led experts to conclude that “MAP7 is involved both in kinesin-1-based transport and microtubule organization in a variety of cell types.” (pmc.ncbi.nlm.nih.gov). It serves as a bridge between the structural microtubule network and the motile machinery of the cell.

Roles in Cell Cycle and DNA Damage Response

Beyond its known functions in interphase cells, emerging research has uncovered roles for MAP7 in the cell cycle and genome maintenance. As discussed, MAP7 associates with spindle microtubules during mitosis, and studies in 2014 (J. Cell Biol.) showed Ensconsin is needed for proper spindle assembly in fly neural stem cells (pmc.ncbi.nlm.nih.gov). It promotes the growth of spindle microtubules and the separation of centrosomes, ensuring a functional bipolar spindle (pmc.ncbi.nlm.nih.gov). In human cells, MAP7’s loading onto the spindle at metaphase suggests it could help stabilize the spindle or assist in chromosome alignment, although the exact molecular role in mitosis in mammals is still being investigated. Intriguingly, a recent study revealed a novel role for MAP7 in DNA double-strand break (DSB) repair during the G1 phase of the cell cycle. In iScience (2023), Dullovi et al. used quantitative proteomics to find proteins that interact with DNA repair factors. They discovered that MAP7 and its paralog MAP7D1 bind to several key DSB repair proteins – including RAD50, BRCA1, and 53BP1 (pubmed.ncbi.nlm.nih.gov). This was unexpected, as these repair factors operate in the nucleus at DNA damage foci, whereas MAP7 is primarily cytoplasmic. The study found that depleting MAP7 or MAP7D1 exacerbated the DNA damage response: cells with reduced MAP7/MAP7D1 had increased p53 phosphorylation after ionizing radiation (indicating more DNA damage stress) and showed a pronounced G1 cell cycle arrest phenotype (pubmed.ncbi.nlm.nih.gov). Moreover, knockdown of MAP7 (especially together with MAP7D1) impaired the repair of DSBs – specifically, RAD50 could not be efficiently recruited to chromatin, and 53BP1 foci at damage sites were diminished in G1-arrested cells lacking MAP7 (pubmed.ncbi.nlm.nih.gov). These results suggest that MAP7 family proteins somehow facilitate proper DNA repair, perhaps by organizing the microtubule network in response to damage or by positioning the nucleus/chromatin for efficient repair complex assembly.

One hypothesis is that microtubule reorganization after DNA damage (a known phenomenon) might involve MAP7 to recruit or modulate repair complexes. Microtubules can influence nuclear processes by transporting signaling proteins or altering nuclear mechanics. The finding that MAP7 physically interacts with BRCA1 and 53BP1, two crucial but antagonistic DNA repair mediators, raises the possibility that MAP7 might coordinate the choice or efficiency of repair pathways (pubmed.ncbi.nlm.nih.gov). It could, for instance, help bring certain repair factors to the vicinity of damaged DNA or anchor the nucleus via cytoskeletal connections during repair. While the precise mechanism remains to be elucidated, this 2023 evidence firmly establishes MAP7 as a player in the DNA damage response – a completely new facet of its function. It underscores the integration between the cytoskeletal system and genome stability mechanisms. Notably, this is the first report linking MAP7 to DNA repair and cell cycle checkpoints (pubmed.ncbi.nlm.nih.gov). It opens interesting questions about whether MAP7’s microtubule stabilization ability is needed to create a scaffold for repair complexes, or whether its motor recruitment function might help ferry repair proteins. In any case, the involvement of MAP7 in guarding genomic integrity further increases the significance of this protein in cell biology.

Regulation by Cellular Stress and Signaling

MAP7’s activity is modulated by various cellular signals and stresses, allowing it to adapt microtubule functions to changing conditions. We have already mentioned phosphorylation control during mitosis and Par-1/MARK kinase regulation during cell polarity establishment. Another layer of regulation comes from osmotic stress and cytoplasmic crowding. The 2024 Dev Cell study by Shen & Ori-McKenney revealed that altering cytoplasmic density (through osmotic shocks) causes rapid changes in MAP7 behavior (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov). Under hyperosmotic conditions (high external salt/sugar, cell shrinks), the cytoplasm becomes crowded and macromolecular diffusion slows – a situation that cells counter by strengthening their cytoskeleton. In this scenario, MAP7 was found to increase its binding to microtubules and promote tubulin acetylation, helping to stabilize microtubules and maintain intracellular transport when diffusion is limited (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov). This leads to a bias in cargo trafficking: cells with more MAP7 association continue moving organelles along microtubules despite the crowded cytosol, thus adapting to osmotic stress (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov). Conversely, under hypoosmotic or dilute conditions, MAP7 disengages from microtubules and detyrosination of tubulin increases (pmc.ncbi.nlm.nih.gov). These coordinated changes show that MAP7 is part of a broader cellular stress-response mechanism, tuning the microtubule network’s stability and the “tubulin code” (PTMs) to ensure vital processes like vesicle transport remain operational in suboptimal conditions (pmc.ncbi.nlm.nih.gov). By promoting acetylation, MAP7 effectively makes microtubules more resilient (acetylated microtubules resist mechanical stress and support continuous organelle movement (pmc.ncbi.nlm.nih.gov)). This insight extends MAP7’s importance to contexts such as osmotic shock, potentially cell migration in varying extracellular matrices (which impose mechanical stress), or volume changes.

Additionally, MAP7 might be regulated by other signaling pathways. Though not extensively detailed in literature, its ability to bind motors suggests it could be a target for signaling cascades that need to rapidly redirect intracellular traffic. For example, growth factor signaling or cell polarity pathways might modulate MAP7 (via phosphorylation or localization changes) to send more motors (and thus cargo) to a particular region of the cell. The MARK kinase example in oocytes demonstrates how spatial cues can confine MAP7 activity, thereby polarizing the flow of cargo (like determinants to the anterior of oocyte) (pmc.ncbi.nlm.nih.gov). Another example is during neuronal branching: local translation or activation of MAP7 in nascent branches could promote microtubule stabilization and organelle delivery to that branch, reinforcing its growth. Indeed, Tymanskyj et al. (2017) found that loss of MAP7 in neurons led to reduced microtubule acetylation specifically in new branches, which corresponded with stunted branch development (pmc.ncbi.nlm.nih.gov). This suggests a feedback where MAP7 is upregulated or activated in regions requiring new microtubule outgrowth.

In summary, MAP7 is not a static component; it is responsive to cell-intrinsic signals (kinase pathways, developmental cues) and extrinsic stress conditions (osmolarity), adjusting the cytoskeletal architecture accordingly. This flexibility is likely crucial for cells to maintain proper function in the face of environmental changes or during complex processes like differentiation and damage repair.

Clinical and Pathological Significance

Given its central roles in cell architecture and transport, it is perhaps not surprising that dysregulation of MAP7 has been implicated in disease, particularly cancer. Many cancers exhibit altered expression of cytoskeletal proteins, and recent studies have identified MAP7 as a factor in tumor cell migration, invasion, and chemotherapy resistance. Large-scale data analyses and patient studies show that MAP7 is frequently upregulated in aggressive cancers. For example, acute myeloid leukemia (AML) patients with high MAP7 expression have significantly worse outcomes. A 2016 clinical study (Fu et al., Sci. Rep. 6:34546) focused on younger AML patients with normal cytogenetics found that elevated MAP7 expression was associated with adverse overall survival and event-free survival (pmc.ncbi.nlm.nih.gov). In that cohort, those in the high-MAP7 group had poorer prognosis (p≈0.04 for OS) than those with low MAP7, and MAP7 remained an independent prognostic marker in multivariate analysis (pmc.ncbi.nlm.nih.gov). This suggests MAP7 contributes to leukemia progression or therapy resistance. Indeed, an earlier study in colon cancer also noted a prognostic link: the ratio of MAP7 to a housekeeping gene (B2M) in tumors could predict survival in stage II colon cancer (pmc.ncbi.nlm.nih.gov). Such correlations indicate that MAP7 might drive more malignant behavior.

Mechanistic studies in solid tumors strengthen the case that MAP7 promotes metastasis and therapy resistance. In cervical cancer (CC), MAP7 expression is significantly higher in tumors than in normal tissue, and high MAP7 levels correlate with poorer survival of patients (Kaplan–Meier analyses p≈0.001) (pmc.ncbi.nlm.nih.gov). Functional assays by Tang et al. (2020) showed that knocking down MAP7 in cervical cancer cell lines dramatically suppressed their migration and invasion capabilities, and increased apoptosis (pmc.ncbi.nlm.nih.gov). Conversely, MAP7 overexpression enhanced cell motility. At the molecular level, one way MAP7 appears to promote cervical cancer progression is by modulating autophagy pathways. Zhang et al. (2020) reported that MAP7 drives CC cell migration/invasion through altering autophagy – for instance, MAP7 knockdown led to accumulation of autophagy markers and more cell death, suggesting that when MAP7 is high, it may help cancer cells maintain pro-survival autophagy at a level that favors migration over cell death (cancerci.biomedcentral.com). Additionally, MAP7 can influence key signaling hubs in cancer cells. In breast cancer, studies found that high MAP7 activates the NF-κB pathway, thereby upregulating genes that promote metastasis and rendering cells less sensitive to chemotherapeutic drugs (like paclitaxel) (pubmed.ncbi.nlm.nih.gov) (pubmed.ncbi.nlm.nih.gov). High MAP7 in breast tumors was associated with increased migration/invasion and with resistance to paclitaxel, a microtubule-targeting drug – possibly because MAP7’s stabilization of microtubules counteracts the drug’s effects (pubmed.ncbi.nlm.nih.gov). This has raised interest in MAP7 as a marker for drug resistance.

Most recently, ovarian cancer research has highlighted MAP7’s role in driving metastasis and chemotherapy (cisplatin) resistance. Chen et al. (Heliyon, 2024) showed that MAP7 overexpression in ovarian cancer cells induces an epithelial-to-mesenchymal transition (EMT) phenotype and activates the Wnt/β-catenin signaling pathway, both of which are strongly linked to metastasis and chemoresistance (pmc.ncbi.nlm.nih.gov). They found that silencing MAP7 in cisplatin-resistant ovarian cancer cells reversed EMT (cells became more epithelial-like) and restored sensitivity to cisplatin (pmc.ncbi.nlm.nih.gov). Notably, MAP7 was observed to mis-localize to the nucleus in these resistant cells (pmc.ncbi.nlm.nih.gov). Once in the nucleus, MAP7 can interact with components of the Wnt pathway – specifically, it was shown to bind the protein CBY1 (Chibby1) (pmc.ncbi.nlm.nih.gov). CBY1 normally sequesters β-catenin and prevents it from activating gene transcription. MAP7 interferes with the CBY1–β-catenin interaction, freeing β-catenin to accumulate in the nucleus and turn on EMT and survival genes (pmc.ncbi.nlm.nih.gov). In essence, cancer cells hijacking MAP7 not only benefit from its cytoskeletal effects (enhanced motility) but also from a gene regulatory effect that boosts a pro-metastatic, drug-resistant program. The study concluded that MAP7 is a “pivotal element” in ovarian cancer progression and cisplatin resistance, and that high MAP7 correlates with worse clinical outcomes, making it a promising prognostic marker and potential therapeutic target (pmc.ncbi.nlm.nih.gov). Importantly, experimental reduction of MAP7 resensitized tumors to cisplatin and reduced their invasive behavior (pmc.ncbi.nlm.nih.gov)，pointing to the feasibility of targeting MAP7 in treatment.

Across cancer types, a recurring theme is that overexpression of MAP7 skews cell behavior toward greater survival, mobility, and stress resistance, likely due to its dual ability to stabilize microtubules (aiding cell structural integrity) and reprogram intracellular trafficking and signaling. Cancer cells with high MAP7 can better withstand microtubule-targeting drugs (by stabilizing their microtubules) (pubmed.ncbi.nlm.nih.gov), avoid apoptosis (possibly via autophagy or NF-κB activation) (pubmed.ncbi.nlm.nih.gov), and migrate through tissues (by reorganizing their cytoskeleton and using motors efficiently). Clinically, assessing MAP7 levels might help stratify patients who are at risk of metastasis or drug resistance. For instance, in cervical cancer patients, MAP7 was found to be an independent predictor of overall survival in multivariate analysis (p=0.001) – second only to lymph node metastasis status (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov). This suggests testing for MAP7 could improve prognostic models. Some cancers (like certain leukemias) might even rely on MAP7 for cell division or survival, although more study is needed there.

Outside of cancer, there are fewer direct disease associations for MAP7. It is not (so far) a known locus for germline mutations causing developmental syndromes in humans. However, given its neuronal roles, researchers have considered it in the context of neurodevelopmental or neurodegenerative disorders. The MAP7 family is expressed in the brain, and perturbations in microtubule stability are a hallmark of neurodegeneration. While the tau protein (MAPT) is heavily studied in Alzheimer’s and related diseases, MAP7’s interplay with tau and kinesin raises the question of whether MAP7 levels or post-translational modifications might contribute to disorders of axonal transport (e.g. some motor neuron diseases or peripheral neuropathies) (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov). To date, no direct link to a human neurological disease gene has been confirmed for MAP7. There is one report connecting MAP7 to a rare bone development disorder (spondylometaphyseal dysplasia), but evidence is limited (www.genecards.org). It’s possible that as sequencing studies expand, subtle variants in MAP7 could be associated with certain conditions (for example, a 2008 study suggested a MAP7 expression ratio could be a prognostic biomarker in colon cancer (pmc.ncbi.nlm.nih.gov), reflecting a role in cell proliferation).

In summary, MAP7 has emerged as an important molecule in cancer biology, where its normal functions are co-opted to advantage tumor cells. Research in the last few years (2020–2024) has solidified MAP7’s involvement in promoting metastasis (through cytoskeletal reorganization and signaling crosstalk) and in enabling resistance to therapies. This makes it a candidate for drug development – for instance, inhibiting MAP7’s interaction with kinesin or with β-catenin might impair a cancer cell’s ability to spread or survive chemo (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov). Some authors have even suggested developing small-molecule MAP7 inhibitors as a novel approach to tackle chemoresistant cancers (pmc.ncbi.nlm.nih.gov). While no such inhibitors are available yet, ongoing research is likely to focus on this translational aspect.

Expert Perspectives and Latest Research

Experts view MAP7 as a bridge between stable microtubule networks and active transport, crucial for specialized cell functions. A 2018 review on microtubule-associated proteins summarized that MAP7/Ensconsin has a dual role: it “is involved both in kinesin-1-based transport and microtubule organization in a variety of cell types.” (pmc.ncbi.nlm.nih.gov) This duality – structural support and motor regulation – sets MAP7 apart from many other MAPs that do primarily one or the other. The same review discussed how MAP7’s regulation by phosphorylation is less about binding affinity and more about spatial targeting, underlining that MAP7 is constitutively a strong binder (it doesn’t fall off microtubules unless specifically instructed by signals) (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov). This property likely explains why it so effectively “ensconces” on microtubules and stays attached even under various conditions. Researchers Keating and Borisy, who first noted a stubborn microtubule-bound factor in 1980, laid the groundwork that later led to MAP7’s discovery (pmc.ncbi.nlm.nih.gov). Decades later, modern techniques like cryo-EM and live-cell imaging have provided atomic detail and real-time insight into MAP7’s function – for example, in 2023, Tan et al. (Nature Commun.) showed exactly how the MAP7 MTBD binds in the microtubule groove and stabilizes protofilaments, explaining earlier observations of its stabilization effect (www.nature.com) (www.nature.com). And Shen et al. (Dev Cell 2024) demonstrated how MAP7 modulates the tubulin code, an emerging concept in cell biology that specific tubulin modifications direct motor traffic and cell signaling (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov). These cutting-edge studies highlight that MAP7 is not a redundant or static MAP, but rather a dynamic regulator with importance in cell stress responses and intracellular communication.

Another key perspective comes from cancer research. A 2022 review in Frontiers in Pharmacology on MAPs in metastasis noted that many MAPs are altered in cancer and can drive invasion and EMT (pmc.ncbi.nlm.nih.gov). While that review focused on several MAP families, it cited evidence that MAP7 upregulation is frequently observed in metastatic cancers and linked to worse outcomes (pmc.ncbi.nlm.nih.gov). For instance, high MAP7 was correlated with advanced disease and poor prognosis in cervical and ovarian cancers, consistent with the primary studies we discussed. This aligns with the idea that microtubule dynamics are key to cancer cell motility, and MAP7, by altering those dynamics (and enhancing plus-end directed transport), pushes cells toward a motile, mesenchymal state. The authors emphasized that targeting MAPs like MAP7 could be a way to interfere with metastasis at the cytoskeletal level (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov). However, they also caution that further in vivo validation is needed (for example, using animal models to see if MAP7 depletion curtails metastasis) (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov).

Latest developments (2023–2024) have expanded MAP7’s known roles: the discovery of its involvement in DNA repair (Dullovi et al. 2023, iScience) adds a novel dimension in cell cycle biology (pubmed.ncbi.nlm.nih.gov) (pubmed.ncbi.nlm.nih.gov), and the detailed dissection of how MAP7 influences microtubule PTMs and cargo transport under stress (Shen & Ori-McKenney 2024) provides mechanistic insight into how cells adapt their interiors to environmental changes (pmc.ncbi.nlm.nih.gov) (pmc.ncbi.nlm.nih.gov). These findings collectively paint MAP7 as a sensor and effector within the cell’s structural network – it senses signals (e.g. stress, developmental cues, DNA damage) and responds by reconfiguring the microtubule scaffold and transport machinery. Such a role is critical for cell survival and function, which is why MAP7 is conserved across species (human MAP7 shares ~81% identity with mouse Map7/Ensconsin (pubmed.ncbi.nlm.nih.gov) and Drosophila Ensconsin can function in mammalian cells, indicating functional conservation).

In conclusion, MAP7 (Ensconsin) is a versatile microtubule-associated protein that stabilizes microtubules and orchestrates motor-based transport. It is vital for maintaining cell polarity in epithelial cells, for proper neuronal axon growth, and for the intracellular positioning of organelles and even nuclei. Its activity is finely regulated by phosphorylation and cellular context, ensuring it engages microtubules at the right place and time (such as on the mitotic spindle or in response to stress). The importance of MAP7 is further underscored by its emerging roles in critical pathways like DNA damage repair and its clear involvement in cancer progression and drug resistance. Ongoing research is likely to delve deeper into MAP7’s interactions (what other proteins does it bind?), its regulation (e.g. are there phosphatases or kinases other than MARK that target it?), and its potential as a therapeutic target in diseases. Given the breadth of processes it influences, MAP7 stands out as a key integrator of the cellular infrastructure – linking the static support role of microtubules with the dynamic needs of intracellular transport and signaling. As one study succinctly stated, understanding MAP7 is essential to understanding “the microtubule landscape” of the cell and how its modulation affects physiology and pathology (pmc.ncbi.nlm.nih.gov). The current understanding, enriched by recent research, solidifies MAP7’s status as a crucial player in cell biology, with relevance from basic science to potential medical applications.

References: (Publication dates and sources for cited works are provided in the citation brackets)

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8. AnnotationURLCitation(end_index=2505, start_index=2371, title='Identification and molecular characterization of E-MAP-115, a novel microtubule-associated protein predominantly expressed in epithelial cells - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/8408219/#:~:text=10.9%20in%20the%20NH2,that%20may%20play%20an%20important')
9. AnnotationURLCitation(end_index=2870, start_index=2727, title='Identification and molecular characterization of E-MAP-115, a novel microtubule-associated protein predominantly expressed in epithelial cells - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/8408219/#:~:text=%28epithelial%20MAP%20of%20115%20kD%29,basic%20with%20a%20pI%20of')
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19. AnnotationURLCitation(end_index=5712, start_index=5562, title='A structural and dynamic visualization of the interaction between MAP7 and microtubules | Nature Communications', type='url_citation', url='https://www.nature.com/articles/s41467-024-46260-5#:~:text=We%20used%20EM%20to%20directly,were%20imaged%20using%20negative%20stain')
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21. AnnotationURLCitation(end_index=6357, start_index=6247, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=Faire%20et%20al,In%20vitro')
22. AnnotationURLCitation(end_index=6938, start_index=6795, title='Identification and molecular characterization of E-MAP-115, a novel microtubule-associated protein predominantly expressed in epithelial cells - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/8408219/#:~:text=%28epithelial%20MAP%20of%20115%20kD%29,basic%20with%20a%20pI%20of')
23. AnnotationURLCitation(end_index=7379, start_index=7236, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=MAP7%20promotes%20and%20protects%20microtubule,acetylation')
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25. AnnotationURLCitation(end_index=8077, start_index=7934, title='Identification and molecular characterization of E-MAP-115, a novel microtubule-associated protein predominantly expressed in epithelial cells - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/8408219/#:~:text=%28epithelial%20MAP%20of%20115%20kD%29,basic%20with%20a%20pI%20of')
26. AnnotationURLCitation(end_index=8345, start_index=8213, title='MAP7 Gene - GeneCards | MAP7 Protein | MAP7 Antibody', type='url_citation', url='https://www.genecards.org/cgi-bin/carddisp.pl?gene=MAP7#:~:text=Microtubule,the%20membrane%20and%20may%20link')
27. AnnotationURLCitation(end_index=8666, start_index=8504, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=HeLa%20cells%20reported%20that%20MAP7,MAP7%20is%20absent%20from%20microtubules')
28. AnnotationURLCitation(end_index=8945, start_index=8814, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=match%20at%20L597%20during%20early,Gallaud%20et')
29. AnnotationURLCitation(end_index=9279, start_index=9171, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=al,Fluorescent%20speckle')
30. AnnotationURLCitation(end_index=9505, start_index=9397, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=al,Fluorescent%20speckle')
31. AnnotationURLCitation(end_index=9788, start_index=9652, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=during%20early%20prophase%2C%20but%20as,Gallaud%20et')
32. AnnotationURLCitation(end_index=10262, start_index=10136, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=Chretien%20D%2C%20Richard,Google%20Scholar')
33. AnnotationURLCitation(end_index=10746, start_index=10626, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=Par,mutations%20of%20six%20predicted')
34. AnnotationURLCitation(end_index=11038, start_index=10898, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=match%20at%20L613%20Par,mutations%20of%20six%20predicted')
35. AnnotationURLCitation(end_index=11320, start_index=11200, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=Par,mutations%20of%20six%20predicted')
36. AnnotationURLCitation(end_index=12129, start_index=11997, title='Identification and molecular characterization of E-MAP-115, a novel microtubule-associated protein predominantly expressed in epithelial cells - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/8408219/#:~:text=novel%20microtubule,that%20may%20play%20an%20important')
37. AnnotationURLCitation(end_index=12443, start_index=12311, title='Identification and molecular characterization of E-MAP-115, a novel microtubule-associated protein predominantly expressed in epithelial cells - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/8408219/#:~:text=novel%20microtubule,that%20may%20play%20an%20important')
38. AnnotationURLCitation(end_index=12714, start_index=12614, title='A structural and dynamic visualization of the interaction between MAP7 and microtubules | Nature Communications', type='url_citation', url='https://www.nature.com/articles/s41467-024-46260-5#:~:text=the%20cytoskeleton,1a')
39. AnnotationURLCitation(end_index=12862, start_index=12715, title='A structural and dynamic visualization of the interaction between MAP7 and microtubules | Nature Communications', type='url_citation', url='https://www.nature.com/articles/s41467-024-46260-5#:~:text=organization%20of%20the%20entire%20MAP7,to%20a%20variety%20of%20post')
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41. AnnotationURLCitation(end_index=13355, start_index=13229, title='A structural and dynamic visualization of the interaction between MAP7 and microtubules | Nature Communications', type='url_citation', url='https://www.nature.com/articles/s41467-024-46260-5#:~:text=determined%20MAP7,is%20not%20altered%20by%20the')
42. AnnotationURLCitation(end_index=13685, start_index=13520, title='A structural and dynamic visualization of the interaction between MAP7 and microtubules | Nature Communications', type='url_citation', url='https://www.nature.com/articles/s41467-024-46260-5#:~:text=match%20at%20L144%20MAP7%20MTBD%3Atubulin%2C,concentration%20ratios%20of%202%3A1%20for')
43. AnnotationURLCitation(end_index=13996, start_index=13830, title='A structural and dynamic visualization of the interaction between MAP7 and microtubules | Nature Communications', type='url_citation', url='https://www.nature.com/articles/s41467-024-46260-5#:~:text=MAP7%20MTBD%3Atubulin%2C%20whereas%20no%20MTs,concentration%20ratios%20of%202%3A1%20for')
44. AnnotationURLCitation(end_index=14693, start_index=14541, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=cellular%20contexts,sterically%20interfering%20with%20vasohibin%201')
45. AnnotationURLCitation(end_index=15118, start_index=14966, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=cellular%20contexts,sterically%20interfering%20with%20vasohibin%201')
46. AnnotationURLCitation(end_index=15593, start_index=15459, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=increasing%20cytoplasmic%20density%20caused%20a,6')
47. AnnotationURLCitation(end_index=15737, start_index=15594, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=MAP7%20promotes%20and%20protects%20microtubule,acetylation')
48. AnnotationURLCitation(end_index=16102, start_index=15928, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=association%20with%20microtubules%20and%20enhances,tightly%20linked%20in%20cells%2C%20but')
49. AnnotationURLCitation(end_index=16287, start_index=16103, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=microtubules%20and%20augments%20microtubule%20detyrosination,tightly%20linked%20in%20cells%2C%20but')
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54. AnnotationURLCitation(end_index=17771, start_index=17622, title='The distribution of murine 115-kDa epithelial microtubule-associated protein (E-MAP-115) during embryogenesis and in adult organs suggests a role in epithelial polarization and differentiation - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/9745708/#:~:text=clearly%20correlates%20with%20the%20degree,is%20so%20far%20unique%20for')
55. AnnotationURLCitation(end_index=18270, start_index=18138, title='MAP7 Gene - GeneCards | MAP7 Protein | MAP7 Antibody', type='url_citation', url='https://www.genecards.org/cgi-bin/carddisp.pl?gene=MAP7#:~:text=Microtubule,the%20membrane%20and%20may%20link')
56. AnnotationURLCitation(end_index=18910, start_index=18781, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=%28Monroy%20et%20al,DRG%29%20neurons%2C%20and')
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61. AnnotationURLCitation(end_index=20552, start_index=20442, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=Faire%20et%20al,In%20vitro')
62. AnnotationURLCitation(end_index=20946, start_index=20836, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=Faire%20et%20al,In%20vitro')
63. AnnotationURLCitation(end_index=21070, start_index=20947, title='A structural and dynamic visualization of the interaction between MAP7 and microtubules | Nature Communications', type='url_citation', url='https://www.nature.com/articles/s41467-024-46260-5#:~:text=match%20at%20L56%20Additionally%2C%20MAP7,16')
64. AnnotationURLCitation(end_index=21363, start_index=21240, title='A structural and dynamic visualization of the interaction between MAP7 and microtubules | Nature Communications', type='url_citation', url='https://www.nature.com/articles/s41467-024-46260-5#:~:text=match%20at%20L56%20Additionally%2C%20MAP7,16')
65. AnnotationURLCitation(end_index=21607, start_index=21484, title='A structural and dynamic visualization of the interaction between MAP7 and microtubules | Nature Communications', type='url_citation', url='https://www.nature.com/articles/s41467-024-46260-5#:~:text=match%20at%20L56%20Additionally%2C%20MAP7,16')
66. AnnotationURLCitation(end_index=22458, start_index=22309, title='MAP7 regulates organelle transport by recruiting kinesin-1 to microtubules - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/31085585/#:~:text=how%20the%20activation%20of%20kinesin,does%20not%20alter%20the%20force')
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73. AnnotationURLCitation(end_index=24396, start_index=24231, title='MAP7 regulates organelle transport by recruiting kinesin-1 to microtubules - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/31085585/#:~:text=reconstituted%20their%20motility%20in%20vitro,greater%20number%20of%20kinesin%20motors')
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76. AnnotationURLCitation(end_index=25299, start_index=25154, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=match%20at%20L584%20MAP7%20competes,DRG%29%20neurons%2C%20and')
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79. AnnotationURLCitation(end_index=27254, start_index=27116, title='Map7D2 and Map7D1 facilitate microtubule stabilization through distinct mechanisms in neuronal cells - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC9039348/#:~:text=mechanisms%20in%20neuronal%20cells%20,Google%20Scholar')
80. AnnotationURLCitation(end_index=27374, start_index=27255, title='A structural and dynamic visualization of the interaction between MAP7 and microtubules | Nature Communications', type='url_citation', url='https://www.nature.com/articles/s41467-024-46260-5#:~:text=13,MAP7%20promotes%20proliferation%20and')
81. AnnotationURLCitation(end_index=27796, start_index=27686, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=Faire%20et%20al,In%20vitro')
82. AnnotationURLCitation(end_index=28054, start_index=27944, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=Faire%20et%20al,In%20vitro')
83. AnnotationURLCitation(end_index=28420, start_index=28265, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=match%20at%20L588%20overexpression%20of,a%20variety%20of%20cell%20types')
84. AnnotationURLCitation(end_index=29030, start_index=28904, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=Chretien%20D%2C%20Richard,Google%20Scholar')
85. AnnotationURLCitation(end_index=29278, start_index=29152, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=Chretien%20D%2C%20Richard,Google%20Scholar')
86. AnnotationURLCitation(end_index=30033, start_index=29914, title='Microtubule-associated proteins MAP7 and MAP7D1 promote DNA double-strand break repair in the G1 cell cycle phase - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/36852271/#:~:text=integrity,a%20strong%20G1%20arrest%20and')
87. AnnotationURLCitation(end_index=30587, start_index=30432, title='Microtubule-associated proteins MAP7 and MAP7D1 promote DNA double-strand break repair in the G1 cell cycle phase - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/36852271/#:~:text=several%20DNA%20repair%20proteins%20including,the%20first%20time%20a%20novel')
88. AnnotationURLCitation(end_index=30973, start_index=30835, title='Microtubule-associated proteins MAP7 and MAP7D1 promote DNA double-strand break repair in the G1 cell cycle phase - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/36852271/#:~:text=to%20increased%20phosphorylation%20of%20p53,strand%20breaks')
89. AnnotationURLCitation(end_index=31801, start_index=31682, title='Microtubule-associated proteins MAP7 and MAP7D1 promote DNA double-strand break repair in the G1 cell cycle phase - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/36852271/#:~:text=integrity,a%20strong%20G1%20arrest%20and')
90. AnnotationURLCitation(end_index=32458, start_index=32324, title='Microtubule-associated proteins MAP7 and MAP7D1 promote DNA double-strand break repair in the G1 cell cycle phase - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/36852271/#:~:text=that%20the%20downregulation%20of%20MAP7,strand%20breaks')
91. AnnotationURLCitation(end_index=33505, start_index=33371, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=increasing%20cytoplasmic%20density%20caused%20a,6')
92. AnnotationURLCitation(end_index=33649, start_index=33506, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=MAP7%20promotes%20and%20protects%20microtubule,acetylation')
93. AnnotationURLCitation(end_index=34201, start_index=34067, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=increasing%20cytoplasmic%20density%20caused%20a,6')
94. AnnotationURLCitation(end_index=34334, start_index=34202, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=In%20BEAS,microtubules%20are%20exposed%20to%20a')
95. AnnotationURLCitation(end_index=34673, start_index=34519, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=density%20by%20modulating%20microtubule%20acetylation%2C,We%20further')
96. AnnotationURLCitation(end_index=34846, start_index=34674, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=match%20at%20L105%20cellular%20contexts,sterically%20interfering%20with%20vasohibin%201')
97. AnnotationURLCitation(end_index=35150, start_index=34976, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=association%20with%20microtubules%20and%20enhances,tightly%20linked%20in%20cells%2C%20but')
98. AnnotationURLCitation(end_index=35592, start_index=35420, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=match%20at%20L105%20cellular%20contexts,sterically%20interfering%20with%20vasohibin%201')
99. AnnotationURLCitation(end_index=35915, start_index=35763, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=cellular%20contexts,sterically%20interfering%20with%20vasohibin%201')
100. AnnotationURLCitation(end_index=36876, start_index=36736, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=match%20at%20L613%20Par,mutations%20of%20six%20predicted')
101. AnnotationURLCitation(end_index=37450, start_index=37280, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=acetylation%20signal%20that%20expanded%20to,acetylation%2C%20but%20not%20vice%20versa')
102. AnnotationURLCitation(end_index=38962, start_index=38827, title='High expression of MAP7 predicts adverse prognosis in young patients with cytogenetically normal acute myeloid leukemia - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5043276/#:~:text=expression%20%28MAP7,I%20genetic%20categories%20and')
103. AnnotationURLCitation(end_index=39283, start_index=39148, title='High expression of MAP7 predicts adverse prognosis in young patients with cytogenetically normal acute myeloid leukemia - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5043276/#:~:text=expression%20%28MAP7,I%20genetic%20categories%20and')
104. AnnotationURLCitation(end_index=39642, start_index=39539, title='High expression of MAP7 predicts adverse prognosis in young patients with cytogenetically normal acute myeloid leukemia - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5043276/#:~:text=10,Google%20Scholar')
105. AnnotationURLCitation(end_index=40209, start_index=40031, title='Enhanced expression of microtubule-associated protein 7 functioned as a contributor to cervical cancer cell migration and is predictive of adverse prognosis - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC7392727/#:~:text=The%20association%20between%20MAP7%20expression,analysis%20revealed%20that%20MAP7%20expression')
106. AnnotationURLCitation(end_index=40571, start_index=40407, title='Enhanced expression of microtubule-associated protein 7 functioned as a contributor to cervical cancer cell migration and is predictive of adverse prognosis - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC7392727/#:~:text=MAP7%20expression%20can%20be%20served,HeLa%20cells%20elevated%20the%20expression')
107. AnnotationURLCitation(end_index=41251, start_index=41092, title='MAP7 promotes migration and invasion and progression of human cervical cancer through modulating the autophagy | Cancer Cell International | Full Text', type='url_citation', url='https://cancerci.biomedcentral.com/articles/10.1186/s12935-020-1095-4#:~:text=MAP7%20promotes%20migration%20and%20invasion,2020')
108. AnnotationURLCitation(end_index=41687, start_index=41532, title='MAP7 Promotes Breast Cancer Cell Migration and Invasion by Regulating the NF-B Pathway - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/36261182#:~:text=MAP7%20Promotes%20Breast%20Cancer%20Cell,Methods%3A%20The%20MAP7%20transcript')
109. AnnotationURLCitation(end_index=41861, start_index=41688, title='MAP7 promotes proliferation and migration of breast cancer cells and reduces the sensitivity of breast cancer cells to paclitaxel - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/35657774/#:~:text=MAP7%20promotes%20proliferation%20and%20migration,breast%20cancer%20cells%20were%20established')
110. AnnotationURLCitation(end_index=42263, start_index=42090, title='MAP7 promotes proliferation and migration of breast cancer cells and reduces the sensitivity of breast cancer cells to paclitaxel - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/35657774/#:~:text=MAP7%20promotes%20proliferation%20and%20migration,breast%20cancer%20cells%20were%20established')
111. AnnotationURLCitation(end_index=42872, start_index=42739, title='MAP7 drives EMT and cisplatin resistance in ovarian cancer via wnt/β-catenin signaling - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11078642/#:~:text=the%20silencing%20of%20MAP7%20attenuates,catenin')
112. AnnotationURLCitation(end_index=43169, start_index=43036, title='MAP7 drives EMT and cisplatin resistance in ovarian cancer via wnt/β-catenin signaling - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11078642/#:~:text=the%20silencing%20of%20MAP7%20attenuates,catenin')
113. AnnotationURLCitation(end_index=43403, start_index=43258, title='MAP7 drives EMT and cisplatin resistance in ovarian cancer via wnt/β-catenin signaling - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11078642/#:~:text=metastasis%20and%20chemoresistance.%20In%20cisplatin,catenin')
114. AnnotationURLCitation(end_index=43718, start_index=43547, title='MAP7 drives EMT and cisplatin resistance in ovarian cancer via wnt/β-catenin signaling - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11078642/#:~:text=In%20summary%2C%20our%20research%20sheds,challenge%20in%20ovarian%20cancer%20treatment')
115. AnnotationURLCitation(end_index=44113, start_index=43942, title='MAP7 drives EMT and cisplatin resistance in ovarian cancer via wnt/β-catenin signaling - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11078642/#:~:text=In%20summary%2C%20our%20research%20sheds,challenge%20in%20ovarian%20cancer%20treatment')
116. AnnotationURLCitation(end_index=44660, start_index=44565, title='MAP7 drives EMT and cisplatin resistance in ovarian cancer via wnt/β-catenin signaling - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11078642/#:~:text=Conclusion')
117. AnnotationURLCitation(end_index=44908, start_index=44775, title='MAP7 drives EMT and cisplatin resistance in ovarian cancer via wnt/β-catenin signaling - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11078642/#:~:text=the%20silencing%20of%20MAP7%20attenuates,catenin')
118. AnnotationURLCitation(end_index=45556, start_index=45383, title='MAP7 promotes proliferation and migration of breast cancer cells and reduces the sensitivity of breast cancer cells to paclitaxel - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/35657774/#:~:text=MAP7%20promotes%20proliferation%20and%20migration,breast%20cancer%20cells%20were%20established')
119. AnnotationURLCitation(end_index=45774, start_index=45619, title='MAP7 Promotes Breast Cancer Cell Migration and Invasion by Regulating the NF-B Pathway - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/36261182#:~:text=MAP7%20Promotes%20Breast%20Cancer%20Cell,Methods%3A%20The%20MAP7%20transcript')
120. AnnotationURLCitation(end_index=46356, start_index=46178, title='Enhanced expression of microtubule-associated protein 7 functioned as a contributor to cervical cancer cell migration and is predictive of adverse prognosis - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC7392727/#:~:text=The%20association%20between%20MAP7%20expression,analysis%20revealed%20that%20MAP7%20expression')
121. AnnotationURLCitation(end_index=46524, start_index=46357, title='Enhanced expression of microtubule-associated protein 7 functioned as a contributor to cervical cancer cell migration and is predictive of adverse prognosis - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC7392727/#:~:text=match%20at%20L327%20remarkably%20associated,002%29%20may%20serve%20as%20independent')
122. AnnotationURLCitation(end_index=47613, start_index=47468, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=match%20at%20L584%20MAP7%20competes,DRG%29%20neurons%2C%20and')
123. AnnotationURLCitation(end_index=47765, start_index=47614, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=MAP7%20competes%20with%20another%20MAP%2C,DRG%29%20neurons%2C%20and')
124. AnnotationURLCitation(end_index=48111, start_index=47986, title='MAP7 Gene - GeneCards | MAP7 Protein | MAP7 Antibody', type='url_citation', url='https://www.genecards.org/cgi-bin/carddisp.pl?gene=MAP7#:~:text=MAP7%20,of%20this%20gene%20is%20MAP7D1')
125. AnnotationURLCitation(end_index=48442, start_index=48339, title='High expression of MAP7 predicts adverse prognosis in young patients with cytogenetically normal acute myeloid leukemia - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5043276/#:~:text=10,Google%20Scholar')
126. AnnotationURLCitation(end_index=49118, start_index=49023, title='MAP7 drives EMT and cisplatin resistance in ovarian cancer via wnt/β-catenin signaling - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11078642/#:~:text=Conclusion')
127. AnnotationURLCitation(end_index=49290, start_index=49119, title='MAP7 drives EMT and cisplatin resistance in ovarian cancer via wnt/β-catenin signaling - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11078642/#:~:text=In%20summary%2C%20our%20research%20sheds,challenge%20in%20ovarian%20cancer%20treatment')
128. AnnotationURLCitation(end_index=49592, start_index=49424, title='MAP7 drives EMT and cisplatin resistance in ovarian cancer via wnt/β-catenin signaling - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11078642/#:~:text=MAP7%2C%20as%20a%20biomarker%20linked,warrants%20further%20research%20and%20efforts')
129. AnnotationURLCitation(end_index=50218, start_index=50089, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=%28Monroy%20et%20al,DRG%29%20neurons%2C%20and')
130. AnnotationURLCitation(end_index=50780, start_index=50614, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=phosphorylation%20effects%20on%20MAP%20activity,rich%20regions%20with%20the%20cell')
131. AnnotationURLCitation(end_index=50901, start_index=50781, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=Par,mutations%20of%20six%20predicted')
132. AnnotationURLCitation(end_index=51338, start_index=51181, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=MAP7%2C%20also%20known%20as%20Ensconsin,Bulinski%20and%20Borisy%2C%201980')
133. AnnotationURLCitation(end_index=51787, start_index=51687, title='A structural and dynamic visualization of the interaction between MAP7 and microtubules | Nature Communications', type='url_citation', url='https://www.nature.com/articles/s41467-024-46260-5#:~:text=the%20cytoskeleton,1a')
134. AnnotationURLCitation(end_index=51914, start_index=51788, title='A structural and dynamic visualization of the interaction between MAP7 and microtubules | Nature Communications', type='url_citation', url='https://www.nature.com/articles/s41467-024-46260-5#:~:text=determined%20MAP7,is%20not%20altered%20by%20the')
135. AnnotationURLCitation(end_index=52262, start_index=52110, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=cellular%20contexts,sterically%20interfering%20with%20vasohibin%201')
136. AnnotationURLCitation(end_index=52395, start_index=52263, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=In%20BEAS,microtubules%20are%20exposed%20to%20a')
137. AnnotationURLCitation(end_index=52934, start_index=52777, title='Emerging role of microtubule-associated proteins on cancer metastasis - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC9515585/#:~:text=The%20major%20cause%20of%20death,site%20and%20function%20in%20microtubule')
138. AnnotationURLCitation(end_index=53249, start_index=53106, title='Emerging role of microtubule-associated proteins on cancer metastasis - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC9515585/#:~:text=129,160298%20%5BDOI%5D%20%5BPubMed%5D%20%5BGoogle%20Scholar')
139. AnnotationURLCitation(end_index=53926, start_index=53755, title='MAP7 drives EMT and cisplatin resistance in ovarian cancer via wnt/β-catenin signaling - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11078642/#:~:text=In%20summary%2C%20our%20research%20sheds,challenge%20in%20ovarian%20cancer%20treatment')
140. AnnotationURLCitation(end_index=54081, start_index=53927, title='MAP7 drives EMT and cisplatin resistance in ovarian cancer via wnt/β-catenin signaling - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11078642/#:~:text=inhibiting%20the%20CBY1,challenge%20in%20ovarian%20cancer%20treatment')
141. AnnotationURLCitation(end_index=54400, start_index=54232, title='MAP7 drives EMT and cisplatin resistance in ovarian cancer via wnt/β-catenin signaling - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11078642/#:~:text=MAP7%2C%20as%20a%20biomarker%20linked,warrants%20further%20research%20and%20efforts')
142. AnnotationURLCitation(end_index=54555, start_index=54401, title='MAP7 drives EMT and cisplatin resistance in ovarian cancer via wnt/β-catenin signaling - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11078642/#:~:text=inhibiting%20the%20CBY1,challenge%20in%20ovarian%20cancer%20treatment')
143. AnnotationURLCitation(end_index=54900, start_index=54754, title='Microtubule-associated proteins MAP7 and MAP7D1 promote DNA double-strand break repair in the G1 cell cycle phase - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/36852271/#:~:text=proteins%20are%20involved%20in%20DNA,the%20first%20time%20a%20novel')
144. AnnotationURLCitation(end_index=55039, start_index=54901, title='Microtubule-associated proteins MAP7 and MAP7D1 promote DNA double-strand break repair in the G1 cell cycle phase - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/36852271/#:~:text=to%20increased%20phosphorylation%20of%20p53,strand%20breaks')
145. AnnotationURLCitation(end_index=55432, start_index=55260, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=match%20at%20L105%20cellular%20contexts,sterically%20interfering%20with%20vasohibin%201')
146. AnnotationURLCitation(end_index=55585, start_index=55433, title='Microtubule-Associated Protein MAP7 Promotes Tubulin Posttranslational Modifications and Cargo Transport to Enable Osmotic Adaptation - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC11187767/#:~:text=cellular%20contexts,sterically%20interfering%20with%20vasohibin%201')
147. AnnotationURLCitation(end_index=56148, start_index=55999, title='The distribution of murine 115-kDa epithelial microtubule-associated protein (E-MAP-115) during embryogenesis and in adult organs suggests a role in epithelial polarization and differentiation - PubMed', type='url_citation', url='https://pubmed.ncbi.nlm.nih.gov/9745708/#:~:text=acid%20sequence%20of%20murine%20E,in%20the%20adult%20intestine%2C%20for')
148. AnnotationURLCitation(end_index=57727, start_index=57598, title='ReMAPping the Microtubule Landscape: How Phosphorylation Dictates the Activities of Microtubule-Associated Proteins - PMC', type='url_citation', url='https://pmc.ncbi.nlm.nih.gov/articles/PMC5739964/#:~:text=%28Monroy%20et%20al,DRG%29%20neurons%2C%20and')