Annotation inferences using phylogenetic trees
Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt
Analysis of mid1p, a protein required for placement of the cell division site, reveals a link between the nucleus and the cell surface in fission yeast.
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Mid1 shuttles between the nucleus and a cortical medial broad band whose position is linked to nuclear position; functional NLS and two CRM1-dependent NES sequences govern this shuttling.
"mid1 protein (mid1p) shuttles between the nucleus and a cortical medial broad band during interphase and early mitosis. The position of this broad band, which overlies the nucleus, is linked to nuclear position even in cells with displaced or multiple nuclei."
Cytokinetic actomyosin ring formation and septation in fission yeast are dependent on the full recruitment of the polo-like kinase Plo1 to the spindle pole body and a functional spindle assembly checkpoint.
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Microtubule depolymerization delays cortical localization of Mid1/Dmf1 and other CAR components, linking ring assembly to Plo1 loading on SPBs.
"Microtubule depolymerisation also delayed the localisation of other CAR components such as actin and Mid1/Dmf1."
Spatial and temporal pathway for assembly and constriction of the contractile ring in fission yeast cytokinesis.
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Mid1 migrates from the nucleus >90 min before SPB separation and specifies a broad equatorial cortical band as the division site, ahead of other ring proteins.
"the anillin-like protein (Mid1p) migrates from the nucleus and specifies a broad band of cortex around the equator as the division site."
Myosin-II reorganization during mitosis is controlled temporally by its dephosphorylation and spatially by Mid1 in fission yeast.
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Mid1 anchors dephosphorylated Myo2 at the medial cortex; Myo2 accumulation at the division site requires Mid1.
"The accumulation of Myo2 requires the anillin homologue Mid1 that functions in proper ring placement."
Requirements of fission yeast septins for complex formation, localization, and function.
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This study concerns S. pombe septins (Spns1-4) and the anillin Mid2p; it does not address mid1. Septin ring organization is a mid2 function.
"Coalescence into ring structures requires Spn1p and Spn4p associate with at least one other septin subunit and the expression of Mid2p that is normally restricted to mitosis."
C-terminal anchoring of mid1p to membranes stabilizes cytokinetic ring position in early mitosis in fission yeast.
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Mid1 binds the medial cortex via a C-terminal amphipathic helix (membrane insertion) and oligomerizes to assemble recruitment platforms that stabilize ring position.
"mid1p C-terminus association with the cortex requires a putative amphipathic helix adjacent to mid1p nuclear localization sequence (NLS), which is predicted to insert directly into the lipid bilayer."
Dynamic positioning of the fission yeast cell division plane.
Cell cycle-dependent roles for the FCH-domain protein Cdc15p in formation of the actomyosin ring in Schizosaccharomyces pombe.
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Ring formation upon metaphase arrest depends on Mid1 when Cdc15 is nonfunctional, a genetic interaction supporting Mid1's ring-assembly role.
"In the absence of functional Cdc15p, ring formation upon metaphase arrest depends on the anillin-like Mid1p."
ORFeome cloning and global analysis of protein localization in the fission yeast Schizosaccharomyces pombe.
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High-throughput ORFeome GFP localization survey; assigned a nuclear envelope signal to Mid1, likely reflecting its nuclear pool.
"ORFeome cloning and global analysis of protein localization in the fission yeast Schizosaccharomyces pombe."
Assembly of the cytokinetic contractile ring from a broad band of nodes in fission yeast.
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Mid1 establishes a broad band of cortical nodes that mature by addition of Myo2, Rng2, Cdc15 and Cdc12 and then coalesce into the contractile ring.
"the anillin-like protein Mid1p establishes a broad band of small dots or nodes in the cortex near the nucleus. These nodes mature by the addition of conventional myosin II (Myo2p, Cdc4p, and Rlc1p), IQGAP (Rng2p), pombe Cdc15 homology protein (Cdc15p), and formin (Cdc12p)."
The Clp1/Cdc14 phosphatase contributes to the robustness of cytokinesis by association with anillin-related Mid1.
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Mid1 is stably anchored at the cell midzone and tethers the Clp1/Cdc14 phosphatase at the contractile ring, underlying its scaffolding role.
"Mid1, unlike other tested CR components, is anchored at the cell midzone, and this physical property is likely to account for its scaffolding role."
Assembly of normal actomyosin rings in the absence of Mid1p and cortical nodes in fission yeast.
Spatial control of cytokinesis by Cdr2 kinase and Mid1/anillin nuclear export.
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Cdr2 anchors Mid1 at the medial cortex during interphase; nuclear export links division-plane position to nuclear position in early mitosis.
"Cdr2 kinase anchors Mid1 at the medial cortex during interphase through association with the Mid1 N terminus."
A spatial gradient coordinates cell size and mitotic entry in fission yeast.
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Mid1 is a component of medial cortical nodes that also contain Wee1, Cdr1 and Cdr2, integrating cell-size sensing with the cell cycle.
"these nodes contain the Cdk1 inhibitor Wee1, the Wee1-inhibitory kinases Cdr1 (also known as Nim1) and Cdr2, and the anillin-like protein Mid1."
Reorganization of the growth pattern of Schizosaccharomyces pombe in invasive filament formation.
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During invasive filament growth, Mid1 localizes similarly to single cells (medial cortex), unlike polarity factors that redistribute.
"a third group acting at different stages of the cell cycle, including Bud6, Rga4, and Mid1, localize similarly in filaments and single cells"
IQGAP-related Rng2p organizes cortical nodes and ensures position of cell division in fission yeast.
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Mid1 recruits Rng2 to cortical nodes; Rng2 then recruits other ring components, ensuring correct division-site placement.
"Mid1p recruits Rng2p to cortical nodes at the division site and that Rng2p, in turn, recruits other components of the actomyosin ring to cortical nodes"
Anillin-related protein Mid1p coordinates the assembly of the cytokinetic contractile ring in fission yeast.
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Orderly contractile-ring assembly depends on Mid1 to recruit Myo2, Rng2 and Cdc15 to nodes and to place cytokinetic nodes around the cell equator.
"orderly assembly of the contractile ring in wild-type cells depends on Mid1p to recruit myosin-II, Rng2p, and Cdc15p to nodes and to place cytokinetic nodes around the cell equator."
Characterization of the roles of Blt1p in fission yeast cytokinesis.
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Mid1 is present in interphase precursor nodes that condense into the contractile ring during mitosis.
"During mitosis, additional proteins join these nodes, which condense to form the contractile ring."
Mechanistic insights into the anchorage of the contractile ring by anillin and Mid1.
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Mid1 binds membranes through a cryptic C2 domain; dimerization yields high affinity/preference for PI(4,5)P2, anchoring Mid1 at the division plane independently of Rho GTPase.
"Dimerization of Mid1 leads to high affinity and preference for PI(4,5)P2, which stably anchors Mid1 at the division plane, bypassing the requirement for Rho GTPase."
Nanoscale architecture of the Schizosaccharomyces pombe contractile ring.
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Membrane-binding scaffolds (including Mid1) occupy the membrane-proximal layer (0-80 nm) of the contractile ring.
"The most membrane-proximal layer (0-80 nm) is composed of membrane-binding scaffolds, formin, and the tail of the essential myosin-II."
NDR Kinase Sid2 Drives Anillin-like Mid1 from the Membrane to Promote Cytokinesis and Medial Division Site Placement.
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The SIN kinase Sid2 phosphorylates Mid1 to remove it from the cortex at constriction onset; Mid1 localizes to nodes, the contractile ring and the nucleus.
"the terminal SIN kinase, Sid2, phosphorylates Mid1 to drive its removal from the cortex at CR constriction onset."
The Functionally Important N-Terminal Half of Fission Yeast Mid1p Anillin Is Intrinsically Disordered and Undergoes Phase Separation.
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The N-terminal half of Mid1 (residues 1-452) is intrinsically disordered and phase-separates into liquid droplets, properties suited to scaffolding node proteins.
"Purified Mid1p-N452 demixes into liquid droplets at concentrations far below its concentration in nodes. These physical properties are appropriate for scaffolding other proteins in nodes."
The dmf1/mid1 gene is essential for correct positioning of the division septum in fission yeast.
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dmf1/mid1 is essential for correct septum positioning; Dmf1p is nuclear in interphase and relocates to a medial cortical ring at mitosis onset with increased phosphorylation.
"In wild-type cells, Dmf1p is nuclear during interphase, and relocates to form a medial ring at the cell cortex coincident with the onset of mitosis."
Role of polo kinase and Mid1p in determining the site of cell division in fission yeast.
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Plo1 is required for Mid1 nuclear exit and ring formation; Plo1 and Mid1 act in a common pathway to recruit medial ring components to the cell center.
"Plo1p is required for Mid1p to exit the nucleus and form a ring, and Pom1p is required for proper placement of the Mid1p ring."