Existing Annotations Review

GO Term	Evidence	Action	Reason
GO:0001731 formation of translation preinitiation complex	IBA GO_REF:0000033	ACCEPT	Summary: Phylogenetic transfer of preinitiation-complex formation, consistent with the experimentally documented role of the MCTS1-DENR complex in assembling tRNA onto 40S/mRNA complexes for (re)initiation. Reason: The IBA is corroborated by direct experimental evidence that MCTS1/DENR promotes recruitment of initiator tRNA to 40S/mRNA complexes when the start codon is in the P-site. Supporting Evidence: file:human/DENR/DENR-uniprot.txt the recruitment in an EIF2-independent manner of aminoacylated initiator tRNA to P site of 40S ribosomes for a new round of translation
GO:0002188 translation reinitiation	IBA GO_REF:0000033	ACCEPT	Summary: Translation reinitiation is the central, defining biological process of DENR, acting in the MCTS1-DENR complex after short uORFs to allow reinitiation at a downstream ORF. Reinitiation is selective for a subset of uORF-containing transcripts (not global uORF control), and DENR is functionally distinct from its single-chain homolog eIF2D. Reason: Strongly supported by both phylogenetic inference and direct experimental evidence (UniProt FUNCTION; ComplexPortal IDA), and is core to DENR function. Recent review/biochemical literature synthesized in the falcon deep research reinforces the uORF-selective reinitiation role of the DENR-MCTS1 complex. Supporting Evidence: file:human/DENR/DENR-uniprot.txt Translation regulator forming a complex with MCTS1 to promote translation reinitiation. file:human/DENR/DENR-deep-research-falcon.md DENR enables post-termination 40S subunits to resume scanning and initiate translation at downstream start codons, most critically at the main ORF of the mRNA
GO:0002183 cytoplasmic translational initiation	IEA GO_REF:0000117	KEEP AS NON CORE	Summary: Automated (ARBA) assignment of cytoplasmic translational initiation. DENR does participate in cytoplasmic (re)initiation, but its specific role is non-canonical reinitiation/recycling rather than canonical initiation. Reason: Broadly correct compartment and process, but more general than DENR's specific reinitiation/recycling role; retained as non-core. Supporting Evidence: file:human/DENR/DENR-uniprot.txt the recruitment in an EIF2-independent manner of aminoacylated initiator tRNA to P site of 40S ribosomes for a new round of translation
GO:0003743 translation initiation factor activity	IEA GO_REF:0000002	ACCEPT	Summary: InterPro/SUI1-domain-based assignment of translation initiation factor activity. DENR contributes the SUI1 module of the MCTS1-DENR complex that delivers tRNA to the 40S P-site, so this molecular function is appropriate. Reason: The eIF2D-like (re)initiation-factor activity is experimentally established for the MCTS1-DENR complex; DENR is an essential subunit. This is a core molecular function. Supporting Evidence: file:human/DENR/DENR-uniprot.txt the recruitment in an EIF2-independent manner of aminoacylated initiator tRNA to P site of 40S ribosomes for a new round of translation
GO:0005737 cytoplasm	IEA GO_REF:0000044	ACCEPT	Summary: Automated cytoplasmic localization, consistent with the experimentally determined cytoplasmic site of action. Reason: Agrees with IDA cytoplasm evidence (PMID:16982740); DENR acts on cytoplasmic ribosomes. Supporting Evidence: file:human/DENR/DENR-uniprot.txt SUBCELLULAR LOCATION: Cytoplasm
GO:0006413 translational initiation	IEA GO_REF:0000002	KEEP AS NON CORE	Summary: General translational initiation, assigned from the SUI1 domain. DENR's specific role is non-canonical reinitiation and recycling rather than canonical cap-dependent initiation. Reason: Correct parent process but less informative than the specific reinitiation role; retained as non-core. Supporting Evidence: file:human/DENR/DENR-uniprot.txt Translation regulator forming a complex with MCTS1 to promote translation reinitiation.
GO:0005515 protein binding	IPI PMID:16169070 A human protein-protein interaction network: a resource for ...	KEEP AS NON CORE	Summary: IntAct interaction with MCTS1 (Q9ULC4), DENR's obligate functional partner. The bare protein binding term is uninformative, but the interaction itself is central to DENR function as part of the MCTS1-DENR heterodimer. Reason: Records a real and functionally pivotal MCTS1 interaction; per curation guidelines bare protein binding is not elevated to core, but the heterodimerization is captured in core_functions. Supporting Evidence: file:human/DENR/DENR-goa.tsv GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:16169070 UniProtKB:Q9ULC4
GO:0005515 protein binding	IPI PMID:16874301 A novel mitochondrial ubiquitin ligase plays a critical role...	KEEP AS NON CORE	Summary: IntAct interactions with UBC (P0CG48) and MARCHF5 (Q9NX47) from a high-throughput screen, unrelated to DENR's reinitiation function. Reason: Bare protein binding from high-throughput screens with partners not connected to the MCTS1-DENR reinitiation/recycling function; uninformative and non-core. Supporting Evidence: file:human/DENR/DENR-goa.tsv GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:16874301 UniProtKB:Q9NX47
GO:0005515 protein binding	IPI PMID:16936636 MARCH-V is a novel mitofusin 2- and Drp1-binding protein abl...	KEEP AS NON CORE	Summary: IntAct interactions with UBC (P0CG48) and MARCHF5 (Q9NX47); high-throughput, not connected to DENR's translation function. Reason: Bare protein binding from high-throughput screens with partners unrelated to reinitiation; uninformative and non-core. Supporting Evidence: file:human/DENR/DENR-goa.tsv GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:16936636 UniProtKB:Q9NX47
GO:0005515 protein binding	IPI PMID:20195357 A comprehensive resource of interacting protein regions for ...	KEEP AS NON CORE	Summary: IntAct interaction with NELFB (Q8WX92) from a high-throughput screen; not related to DENR's reinitiation/recycling function. Reason: Bare protein binding from a high-throughput screen with a partner unrelated to DENR's core function; uninformative. Supporting Evidence: file:human/DENR/DENR-goa.tsv GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:20195357 UniProtKB:Q8WX92
GO:0005515 protein binding	IPI PMID:21516116 Next-generation sequencing to generate interactome datasets.	KEEP AS NON CORE	Summary: IntAct interaction with MCTS1 (Q9ULC4), the obligate DENR partner. Reason: Records the functionally central MCTS1 interaction; bare protein binding is not elevated to core but the heterodimer is captured in core_functions. Supporting Evidence: file:human/DENR/DENR-goa.tsv GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:21516116 UniProtKB:Q9ULC4
GO:0005515 protein binding	IPI PMID:32296183 A reference map of the human binary protein interactome.	KEEP AS NON CORE	Summary: IntAct interaction with MCTS1 (Q9ULC4), the obligate DENR partner. Reason: Records the functionally central MCTS1 interaction; bare protein binding is not elevated to core but the heterodimer is captured in core_functions. Supporting Evidence: file:human/DENR/DENR-goa.tsv GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:32296183 UniProtKB:Q9ULC4
GO:0005515 protein binding	IPI PMID:33961781 Dual proteome-scale networks reveal cell-specific remodeling...	KEEP AS NON CORE	Summary: BioPlex interactions including MCTS1 (Q9ULC4) and MAPT/tau (P10636). The MCTS1 interaction is functionally central; the tau interaction is a high-throughput observation. Reason: Captures the functionally central MCTS1 interaction (alongside a peripheral tau hit); bare protein binding is not elevated to core. Supporting Evidence: file:human/DENR/DENR-goa.tsv GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:33961781 UniProtKB:Q9ULC4
GO:0005515 protein binding	IPI PMID:34757590 Targeting Tau Mitigates Mitochondrial Fragmentation and Oxid...	KEEP AS NON CORE	Summary: IntAct interaction with MAPT/tau (P10636) from a high-throughput study; not connected to DENR's reinitiation function. Reason: Bare protein binding from a high-throughput screen with tau, unrelated to DENR's core function; uninformative. Supporting Evidence: file:human/DENR/DENR-goa.tsv GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:34757590 UniProtKB:P10636
GO:0005515 protein binding	IPI PMID:40205054 Multimodal cell maps as a foundation for structural and func...	KEEP AS NON CORE	Summary: Cell-maps interactome interaction with MCTS1 (Q9ULC4), the obligate DENR partner. Reason: Records the functionally central MCTS1 interaction; bare protein binding is not elevated to core but is captured in core_functions. Supporting Evidence: file:human/DENR/DENR-goa.tsv GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:40205054 UniProtKB:Q9ULC4
GO:0002188 translation reinitiation	IDA PMID:37875108 Human MCTS1-dependent translation of JAK2 is essential for I...	ACCEPT	Summary: Direct evidence (ComplexPortal/IDA) that the MCTS1-DENR complex mediates translation reinitiation, demonstrated for JAK2 and other targets. Reason: Direct experimental support for the core reinitiation function of DENR within the MCTS1-DENR complex. Supporting Evidence: file:human/DENR/DENR-uniprot.txt Translation regulator forming a complex with MCTS1 to promote translation reinitiation.
GO:0070992 translation initiation complex	IPI PMID:29889857 DENR-MCTS1 heterodimerization and tRNA recruitment are requi...	ACCEPT	Summary: DENR is part of the MCTS1-DENR (re)initiation complex; heterodimerization with MCTS1 and tRNA recruitment are required for reinitiation. Reason: Supported by structural/biochemical demonstration that DENR-MCTS1 heterodimerize to form the functional reinitiation complex. Supporting Evidence: PMID:29889857 DENR-MCTS1 heterodimerization and tRNA recruitment are required for translation reinitiation
GO:0005515 protein binding	IPI PMID:16982740 MCT-1 protein interacts with the cap complex and modulates m...	KEEP AS NON CORE	Summary: UniProt-curated interaction with MCTS1 (Q9ULC4); this is the foundational report that DENR/DRP is recruited by MCTS1 via the PUA/SUI1 interface. Reason: Records the functionally central MCTS1 interaction; bare protein binding is not elevated to core but the heterodimer is captured in core_functions. Supporting Evidence: PMID:16982740 recruits the density-regulated protein (DENR/DRP), containing the SUI1 translation initiation domain
GO:0005737 cytoplasm	IDA PMID:16982740 MCT-1 protein interacts with the cap complex and modulates m...	ACCEPT	Summary: Direct evidence that DENR is active in the cytoplasm, where it associates with the cap complex/translation machinery via MCTS1. Reason: IDA-supported cytoplasmic site of action, consistent with DENR's role on cytoplasmic ribosomes. Supporting Evidence: file:human/DENR/DENR-uniprot.txt SUBCELLULAR LOCATION: Cytoplasm
GO:0075522 IRES-dependent viral translational initiation	IDA PMID:20713520 Activities of Ligatin and MCT-1/DENR in eukaryotic translati...	KEEP AS NON CORE	Summary: MCT-1/DENR promotes eIF2-independent recruitment of initiator tRNA on HCV-like IRESs and SV 26S mRNA, where the start codon is placed directly in the P-site. Reason: A genuine but specialized application of DENR's P-site tRNA delivery activity (viral IRES context); retained as non-core relative to cellular reinitiation. Supporting Evidence: PMID:20713520 promote efficient eIF2-independent recruitment of Met-tRNA(Met)(i) to 40S/mRNA complexes, if attachment of 40S subunits to the mRNA places the initiation codon directly in the P site, as on HCV-like IRESs
GO:0001731 formation of translation preinitiation complex	IDA PMID:20713520 Activities of Ligatin and MCT-1/DENR in eukaryotic translati...	ACCEPT	Summary: Direct evidence that MCT-1/DENR assembles initiator tRNA onto 40S/mRNA complexes, forming a preinitiation-type complex for reinitiation/recycling. Reason: Direct experimental support for DENR's role in assembling the tRNA-loaded 40S complex. Supporting Evidence: PMID:20713520 promote efficient eIF2-independent recruitment of Met-tRNA(Met)(i) to 40S/mRNA complexes
GO:0032790 ribosome disassembly	IDA PMID:20713520 Activities of Ligatin and MCT-1/DENR in eukaryotic translati...	ACCEPT	Summary: MCT-1/DENR promotes release of deacylated tRNA and mRNA from recycled 40S subunits after ABCE1-mediated splitting of post-termination ribosomes, i.e. the recycling/recovery step. Recent reviews reinforce that this tRNA-release/40S-recycling activity (a property of the DENR-MCTS1 complex) is a defining function and that penultimate-codon identity in the uORF modulates the efficiency of DENR-MCTS1-dependent recycling. Reason: Direct experimental support for DENR's role in 40S recycling (clearing deacylated tRNA/mRNA), a core part of its function, corroborated by recent review literature synthesized in the falcon deep research. Recycling is a property of the DENR-MCTS1 heterodimer, of which DENR is the essential SUI1-bearing subunit. Supporting Evidence: PMID:20713520 Ligatin and MCT-1/DENR can promote release of deacylated tRNA and mRNA from recycled 40S subunits after ABCE1-mediated dissociation of post-termination ribosomes file:human/DENR/DENR-deep-research-falcon.md This tRNA release is essential for 40S ribosome dissociation from mRNA and recycling back into the translational pool

Core Functions

As an essential subunit of the MCTS1-DENR heterodimer (an eIF2D-like non-canonical factor), provides the SUI1 module that delivers aminoacylated tRNA into the 40S ribosomal P-site in an eIF2-independent manner to drive translation reinitiation after short uORFs.

Molecular Function:

translation initiation factor activity

Cellular Locations:

cytoplasm

Supporting Evidence:

file:human/DENR/DENR-uniprot.txt
the recruitment in an EIF2-independent manner of aminoacylated initiator tRNA to P site of 40S ribosomes for a new round of translation
PMID:29889857
DENR-MCTS1 heterodimerization and tRNA recruitment are required for translation reinitiation

Within the MCTS1-DENR complex, promotes recycling/recovery of post-termination 40S subunits by promoting dissociation of deacylated tRNA and mRNA after ABCE1-mediated ribosome splitting.

Molecular Function:

translation initiation factor activity

Cellular Locations:

cytoplasm

Supporting Evidence:

PMID:20713520
Ligatin and MCT-1/DENR can promote release of deacylated tRNA and mRNA from recycled 40S subunits after ABCE1-mediated dissociation of post-termination ribosomes
file:human/DENR/DENR-deep-research-falcon.md
to facilitate the removal of deacylated tRNA from the ribosomal P-site

References

file:human/DENR/DENR-deep-research-falcon.md

Falcon deep research report for DENR

The DENR-MCTS1 complex acts on post-termination 40S ribosomal subunits to facilitate removal of deacylated tRNA from the P-site, which is essential for 40S dissociation from mRNA and recycling back into the translational pool.
DENR-MCTS1 promotes translation reinitiation, particularly after short uORFs in 5'UTRs, and this reinitiation is selective for only a subset of uORF-containing transcripts; DENR is functionally distinct from its single-chain homolog eIF2D.
Under oxidative (arsenite) stress, DENR relocalizes together with MCTS1, eIF2D, ABCE1, eRF1 and eRF3 to cytoplasmic stress granules, suggesting spatial regulation of post-termination/reinitiation factors during stress.

GO_REF:0000002

Gene Ontology annotation through association of InterPro records with GO terms

GO_REF:0000033

Annotation inferences using phylogenetic trees

GO_REF:0000044

Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping

GO_REF:0000117

Electronic Gene Ontology annotations created by ARBA machine learning models

PMID:16169070

A human protein-protein interaction network: a resource for annotating the proteome.

PMID:16874301

A novel mitochondrial ubiquitin ligase plays a critical role in mitochondrial dynamics.

PMID:16936636

MARCH-V is a novel mitofusin 2- and Drp1-binding protein able to change mitochondrial morphology.

PMID:16982740

MCT-1 protein interacts with the cap complex and modulates messenger RNA translational profiles.

MCT-1 (MCTS1) interacts with the cap complex through its PUA domain and recruits DENR/DRP, which contains the SUI1 translation initiation domain.

PMID:20195357

A comprehensive resource of interacting protein regions for refining human transcription factor networks.

PMID:20713520

Activities of Ligatin and MCT-1/DENR in eukaryotic translation initiation and ribosomal recycling.

MCT-1 and DENR (homologous to N- and C-terminal regions of Ligatin) together promote eIF2-independent recruitment of initiator tRNA to 40S/mRNA complexes when the initiation codon is placed directly in the P-site.
MCT-1/DENR can promote release of deacylated tRNA and mRNA from recycled 40S subunits after ABCE1-mediated dissociation of post-termination ribosomes.

PMID:21516116

Next-generation sequencing to generate interactome datasets.

PMID:29889857

DENR-MCTS1 heterodimerization and tRNA recruitment are required for translation reinitiation.

DENR and MCTS1 heterodimerize and this, together with tRNA recruitment, is required for translation reinitiation.

PMID:32296183

A reference map of the human binary protein interactome.

PMID:33961781

Dual proteome-scale networks reveal cell-specific remodeling of the human interactome.

PMID:34757590

Targeting Tau Mitigates Mitochondrial Fragmentation and Oxidative Stress in Amyotrophic Lateral Sclerosis.

PMID:37875108

Human MCTS1-dependent translation of JAK2 is essential for IFN-γ immunity to mycobacteria.

MCTS1-DENR-dependent translation reinitiation is required for translation of JAK2 and for IFN-gamma immunity to mycobacteria.

PMID:40205054

Multimodal cell maps as a foundation for structural and functional genomics.

Suggested Experiments

Experiment: Ribosome profiling in DENR-knockout versus wild-type cells to map reinitiation-dependent mORFs genome-wide and define uORF determinants of MCTS1-DENR dependence.

Experiment: Reconstituted 40S recycling assays with purified DENR/MCTS1, ABCE1 and post-termination complexes to quantify the kinetics of deacylated tRNA/mRNA release contributed by DENR.

Deep Research

Falcon

(DENR-deep-research-falcon.md)

Comprehensive Research Report on DENR (Density-Regulated Protein) Falcon Edison Scientific Literature 18 citations 1 artifacts 2026-06-20T07:10:06.109531

Edison artifact artifact-00 (text/markdown)

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.

Comprehensive Research Report on DENR (Density-Regulated Protein)

Gene and Protein Identity Verification

The gene DENR (UniProt: O43583) encodes the density-regulated protein (DRP), also known as DRP1 or SMAP-3 (smooth muscle cell-associated protein 3), in humans (bohlen2023humanmcts1dependenttranslation pages 1-3, grove2024toinitiateor pages 2-4, grove2024toinitiateor pages 1-2). This identification is consistent with the UniProt annotation and the protein belongs to the DENR family with characteristic DENR/SUI1_TIF, DENR_C, and DENR_N domains (grove2024toinitiateor pages 2-4, grove2024toinitiateor pages 1-2). The literature unambiguously refers to this protein in the context of translation regulation, ribosome recycling, and reinitiation (grove2024toinitiateor pages 2-4, hohenberg2022cyclinbcdk1and pages 1-2, young2022rebirthofthe pages 1-3).

Primary Molecular Function

DENR functions as a non-canonical translation initiation factor that operates in complex with its obligate partner MCTS1 (multiple copies in T-cell lymphoma 1) (grove2024toinitiateor pages 2-4, hohenberg2022cyclinbcdk1and pages 1-2, bohlen2023humanmcts1dependenttranslation pages 5-6). The DENR·MCTS1 heterodimeric complex has two primary molecular functions that are intrinsically linked:

1. Ribosome Recycling

Following translation termination, the DENR·MCTS1 complex acts on post-termination 40S ribosomal subunits to facilitate the removal of deacylated tRNA from the ribosomal P-site (grove2024toinitiateor pages 2-4, young2022rebirthofthe pages 1-3, sherlock2023principlesmechanismsand pages 1-3). This tRNA release is essential for 40S ribosome dissociation from mRNA and recycling back into the translational pool (young2022rebirthofthe pages 1-3, jendruchova2024differentialeffectsof pages 1-2). The efficiency of DENR-mediated tRNA removal depends on the identity of the penultimate codon in the translated open reading frame (ORF), with certain codons conferring heightened dependence on DENR·MCTS1 for efficient recycling (jendruchova2024differentialeffectsof pages 1-2).

2. Translation Reinitiation

The DENR·MCTS1 complex promotes translation reinitiation, particularly after short upstream open reading frames (uORFs) located in the 5' untranslated regions (5'UTRs) of mRNAs (hohenberg2022cyclinbcdk1and pages 1-2, meurs2025mcts2anddistinct pages 1-2, meurs2025mcts2anddistinct pages 2-3). In this capacity, DENR enables post-termination 40S subunits to resume scanning and initiate translation at downstream start codons, most critically at the main ORF of the mRNA (sherlock2023principlesmechanismsand pages 1-3, meurs2025mcts2anddistinct pages 1-2). This reinitiation function is selective—only a subset of uORF-containing transcripts exhibit DENR-dependent reinitiation (meurs2025mcts2anddistinct pages 1-2, meurs2025mcts2anddistinct pages 2-3).

Biochemical Mechanism and Substrate Specificity

The biochemical mechanism of DENR has been elucidated through both in vitro reconstitution studies and ribosome profiling experiments in cells (grove2024toinitiateor pages 2-4, meurs2025mcts2anddistinct pages 1-2, meurs2025mcts2anddistinct pages 2-3). DENR·MCTS1 exhibits dual biochemical activities: it can both recruit and release initiator tRNA (Met-tRNAi) from the ribosomal P-site (grove2024toinitiateor pages 2-4, meurs2025mcts2anddistinct pages 2-3). The current evidence most strongly supports that DENR·MCTS1 primarily functions by removing deacylated tRNA from post-termination 40S complexes, thereby restoring their scanning competence and permitting subsequent rounds of translation initiation (young2022rebirthofthe pages 1-3, sherlock2023principlesmechanismsand pages 1-3, meurs2025mcts2anddistinct pages 2-3).

Substrate Specificity

DENR does not function as a general translation factor but rather exhibits transcript-selective activity (meurs2025mcts2anddistinct pages 1-2, meurs2025mcts2anddistinct pages 2-3). Key determinants of DENR-dependence include:

uORF architecture: Short uORFs, including single-codon "start-stop" uORFs (AUG immediately followed by a stop codon), are particularly enriched among DENR targets, though longer uORFs also show DENR-dependence (meurs2025mcts2anddistinct pages 1-2, meurs2025mcts2anddistinct pages 2-3)
Penultimate codon identity: Specific penultimate codons preceding the uORF stop codon confer differential dependence on DENR·MCTS1 for deacylated tRNA release (jendruchova2024differentialeffectsof pages 1-2)
Retention of initiation factors: mRNAs where initiation factors like eIF3 remain associated with post-termination 40S complexes show enhanced DENR-dependent reinitiation (jendruchova2024differentialeffectsof pages 1-2)

Importantly, DENR is functionally distinct from its structural homolog eIF2D, which contains similar domains encoded on a single polypeptide but regulates a different subset of transcripts (meurs2025mcts2anddistinct pages 1-2, meurs2025mcts2anddistinct pages 2-3).

Subcellular Localization

DENR is predominantly localized to the cytoplasm where it functions on ribosome-associated complexes during translation (makeeva2023relocalizationoftranslation pages 1-2, bohlen2023humanmcts1dependenttranslation pages 5-6). The protein is ubiquitously expressed across all cell types and tissues in humans (bohlen2023humanmcts1dependenttranslation pages 5-6).

Under cellular stress conditions, specifically oxidative stress induced by arsenite treatment, DENR undergoes dynamic relocalization to stress granules—cytoplasmic ribonucleoprotein condensates containing untranslated mRNAs, 40S ribosomal subunits, and various translation factors (makeeva2023relocalizationoftranslation pages 1-2). This relocalization occurs together with its partner MCTS1, as well as with translation termination factors (eRF1, eRF3) and other ribosome recycling factors (ABCE1, eIF2D) (makeeva2023relocalizationoftranslation pages 1-2). The sequestration of these post-termination and reinitiation factors to stress granules may serve to spatially regulate translation recovery after stress relief and contribute to the rapid resumption of mRNA translation upon stress granule disassembly (makeeva2023relocalizationoftranslation pages 1-2).

Biological Pathways and Processes

DENR participates in several specific biochemical and signaling pathways through its selective translational control of uORF-containing mRNAs:

1. Integrated Stress Response (ISR)

DENR·MCTS1 promotes translation of ATF4 (activating transcription factor 4), a master transcriptional regulator of the integrated stress response (wek2023survivingandadapting pages 1-2). ATF4 translation is induced under conditions of eIF2α phosphorylation during endoplasmic reticulum stress, amino acid deprivation, and other cellular stresses (wek2023survivingandadapting pages 1-2). The 5'UTR of ATF4 mRNA contains regulatory uORFs that, under stress conditions, allow preferential translation of the ATF4 coding sequence in a DENR-dependent manner (wek2023survivingandadapting pages 1-2). This enables cells to mount adaptive responses to stress while global translation is repressed (wek2023survivingandadapting pages 1-2).

2. Cell Cycle and Mitotic Translational Control

DENR undergoes dynamic regulation during the cell cycle through phosphorylation at Serine 73 by Cyclin B/CDK1 and Cyclin A/CDK2 kinases (hohenberg2022cyclinbcdk1and pages 1-2, hohenberg2022cyclinbcdk1and pages 2-3). This phosphorylation occurs at mitotic entry, peaks during early mitosis (prophase, prometaphase, metaphase), and is subsequently removed as cells exit mitosis (hohenberg2022cyclinbcdk1and pages 1-2, hohenberg2022cyclinbcdk1and pages 2-3). Phosphorylation at Ser73 stabilizes DENR protein by preventing its cleavage at Asp26, leading to enhanced translation of mRNAs involved in mitotic processes (hohenberg2022cyclinbcdk1and pages 1-2). Remarkably, approximately 40% of all mRNAs displaying elevated translation during mitosis are DENR targets, demonstrating that DENR is a central regulator linking cell cycle progression to phase-specific translational programs (hohenberg2022cyclinbcdk1and pages 1-2). In the absence of DENR or when Ser73 phosphorylation is prevented, cells display elevated levels of aberrant mitoses and increased cell death (hohenberg2022cyclinbcdk1and pages 1-2).

3. Immune Signaling and Antimycobacterial Immunity

A critical physiological role for DENR emerged from the discovery of X-linked recessive MCTS1 deficiency in male patients with Mendelian susceptibility to mycobacterial disease (MSMD) (bohlen2023humanmcts1dependenttranslation pages 1-3, bohlen2023humanmcts1dependenttranslation pages 5-6). In these patients, complete absence of MCTS1 leads to loss of DENR protein stability and function (bohlen2023humanmcts1dependenttranslation pages 5-6). The molecular basis of their disease phenotype is selective impairment in DENR-dependent translation of JAK2 (Janus kinase 2) (bohlen2023humanmcts1dependenttranslation pages 1-3, bohlen2023humanmcts1dependenttranslation pages 5-6). Reduced JAK2 expression specifically impairs cellular responses to IL-23 (and partially IL-12), which preferentially affects IFN-γ production by innate-like adaptive T lymphocytes (MAIT cells and γδ T cells) upon mycobacterial challenge (bohlen2023humanmcts1dependenttranslation pages 1-3, bohlen2023humanmcts1dependenttranslation pages 5-6). This pathway demonstrates that DENR-mediated translational control of specific immune signaling molecules is non-redundant and essential for antimicrobial immunity (bohlen2023humanmcts1dependenttranslation pages 1-3, bohlen2023humanmcts1dependenttranslation pages 5-6).

4. Neurological Function and Development

DENR and MCTS1 have roles in neurobiology, and loss-of-function mutations in DENR are associated with impaired neurocortical migration and brain developmental disorders (hohenberg2022cyclinbcdk1and pages 1-2). Additionally, DENR knockdown suppresses repeat-associated non-AUG (RAN) translation of expanded GGGGCC and CGG repeats associated with C9orf72 ALS/FTD and fragile X-associated tremor/ataxia syndrome (FXTAS), respectively (green2022noncanonicalinitiationfactors pages 1-2). These findings suggest DENR may contribute to both normal neuronal development and pathological protein production in repeat expansion disorders (green2022noncanonicalinitiationfactors pages 1-2).

Protein Interactions and Regulatory Partners

MCTS1 (Primary Partner)

DENR forms a constitutive heterodimer with MCTS1, and the two proteins are functionally and biochemically interdependent (hohenberg2022cyclinbcdk1and pages 1-2, bohlen2023humanmcts1dependenttranslation pages 5-6). MCTS1 contains DUF1947 and PUA (RNA-binding) domains that complement DENR's SWIB/MDM2 and SUI/eIF1-like domains (grove2024toinitiateor pages 2-4, bohlen2023humanmcts1dependenttranslation pages 5-6). In cells lacking MCTS1, DENR protein levels are markedly reduced, demonstrating that MCTS1 is required for DENR stability (bohlen2023humanmcts1dependenttranslation pages 5-6). The DENR·MCTS1 complex has been validated across multiple model systems including yeast (Tma22/Tma20), Drosophila, and mammals, demonstrating evolutionary conservation of this partnership (meurs2025mcts2anddistinct pages 1-2, meurs2025mcts2anddistinct pages 2-3, jendruchova2024differentialeffectsof pages 1-2).

MCTS2 (Alternative Partner)

Recent work identified MCTS2, encoded by a retrogene copy of MCTS1 on chromosome 20, as an alternative DENR-binding partner (meurs2025mcts2anddistinct pages 1-2, meurs2025mcts2anddistinct pages 2-3). MCTS2 shares ~95% sequence identity with MCTS1 and can promote reinitiation in vitro, albeit with weaker activity than MCTS1 (meurs2025mcts2anddistinct pages 1-2, meurs2025mcts2anddistinct pages 2-3). The discovery of MCTS2 provides a plausible molecular explanation for the clinical differences observed between patients with DENR versus MCTS1 mutations in humans, as MCTS2 may partially compensate for MCTS1 loss but cannot substitute for DENR (meurs2025mcts2anddistinct pages 1-2, meurs2025mcts2anddistinct pages 2-3).

Ribosome and tRNA Interactions

DENR directly binds the 40S ribosomal subunit and interacts with initiator tRNA (Met-tRNAi) in the context of post-termination complexes (grove2024toinitiateor pages 2-4, meurs2025mcts2anddistinct pages 2-3). These interactions are essential for its tRNA release and reinitiation activities (grove2024toinitiateor pages 2-4).

Regulatory Kinases

Cyclin B/CDK1 and Cyclin A/CDK2 are the primary kinases that phosphorylate DENR at Ser73 during the cell cycle (hohenberg2022cyclinbcdk1and pages 1-2, hohenberg2022cyclinbcdk1and pages 2-3). This phosphorylation is both necessary and sufficient to enhance DENR stability and promote translation of mitotic target mRNAs (hohenberg2022cyclinbcdk1and pages 1-2, hohenberg2022cyclinbcdk1and pages 2-3).

Relationship to eIF2D

DENR·MCTS1 is structurally and functionally related to eIF2D (also called ligatin), which contains DENR-like and MCTS1-like domains on a single polypeptide chain (grove2024toinitiateor pages 2-4, meurs2025mcts2anddistinct pages 1-2). However, extensive evidence indicates that DENR·MCTS1 and eIF2D have distinct target specificities and non-redundant functions in vivo (meurs2025mcts2anddistinct pages 1-2, meurs2025mcts2anddistinct pages 2-3). While both factors can participate in ribosome recycling and have been implicated in reinitiation contexts, eIF2D knockdown causes widespread gene expression changes unrelated to uORF translation, suggesting functions distinct from MCTS1-DENR-dependent reinitiation regulation (meurs2025mcts2anddistinct pages 1-2, meurs2025mcts2anddistinct pages 2-3).

Summary Table

Aspect	Details	Citations
Protein domains and structure	Human DENR (UniProt O43583) is the density-regulated protein also called DRP/SMAP-3 and belongs to the DENR family. Functionally, DENR is the DENR-containing half of the DENR·MCTS1 heterodimer, which is structurally and functionally related to eIF2D; DENR contributes SWIB/MDM2-SUI/eIF1-like features implicated in post-termination 40S complexes, whereas MCTS1 contributes complementary domains in the heterodimer. Recent reviews discuss MCT-1·DENR as a distinct non-canonical translation factor complex acting at the ribosome. (grove2024toinitiateor pages 2-4, hohenberg2022cyclinbcdk1and pages 1-2, jendruchova2024differentialeffectsof pages 1-2)	(grove2024toinitiateor pages 2-4, hohenberg2022cyclinbcdk1and pages 1-2, jendruchova2024differentialeffectsof pages 1-2)
Primary molecular function	DENR is a non-canonical translation factor whose core function is to support post-termination ribosome recycling and translation reinitiation, especially after translation of short upstream ORFs (uORFs). In mammalian systems, DENR promotes expression of selected mRNAs whose main ORF translation depends on efficient reinitiation after a uORF. (hohenberg2022cyclinbcdk1and pages 1-2, young2022rebirthofthe pages 1-3, meurs2025mcts2anddistinct pages 1-2, bohlen2023humanmcts1dependenttranslation pages 5-6, meurs2025mcts2anddistinct pages 2-3)	(hohenberg2022cyclinbcdk1and pages 1-2, young2022rebirthofthe pages 1-3, meurs2025mcts2anddistinct pages 1-2, bohlen2023humanmcts1dependenttranslation pages 5-6, meurs2025mcts2anddistinct pages 2-3)
Biochemical mechanism	Biochemical studies summarized in recent reviews indicate that the DENR·MCTS1 complex acts on post-termination 40S ribosomes to promote release of deacylated tRNA from the P site and thereby facilitate 40S recycling/scanning competence; DENR·MCTS1 has also been reported to bind/recruit initiator tRNA under some settings. Current expert assessment emphasizes that the strongest evidence supports roles in recycling and reinitiation, with transcript- and context-specific effects on initiation remaining an active area of investigation. Penultimate uORF codon identity and uORF architecture influence DENR dependence. (grove2024toinitiateor pages 2-4, young2022rebirthofthe pages 1-3, sherlock2023principlesmechanismsand pages 1-3, meurs2025mcts2anddistinct pages 1-2, meurs2025mcts2anddistinct pages 2-3, jendruchova2024differentialeffectsof pages 1-2)	(grove2024toinitiateor pages 2-4, young2022rebirthofthe pages 1-3, sherlock2023principlesmechanismsand pages 1-3, meurs2025mcts2anddistinct pages 1-2, meurs2025mcts2anddistinct pages 2-3, jendruchova2024differentialeffectsof pages 1-2)
Protein partners	The key obligate partner is MCTS1, a constitutive binding partner interdependent with DENR for function and, in patient-derived cells lacking MCTS1, DENR protein levels are reduced. DENR also directly engages the 40S ribosomal subunit and tRNA-containing post-termination complexes. CDK1/Cyclin B1 and CDK2/Cyclin A2 phosphorylate DENR on Ser73 in mitosis. More recent work identified MCTS2 as an alternative DENR partner that can promote reinitiation in vitro. DENR is mechanistically related, but not identical, to eIF2D. (hohenberg2022cyclinbcdk1and pages 1-2, meurs2025mcts2anddistinct pages 1-2, bohlen2023humanmcts1dependenttranslation pages 5-6, meurs2025mcts2anddistinct pages 2-3, hohenberg2022cyclinbcdk1and pages 2-3)	(hohenberg2022cyclinbcdk1and pages 1-2, meurs2025mcts2anddistinct pages 1-2, bohlen2023humanmcts1dependenttranslation pages 5-6, meurs2025mcts2anddistinct pages 2-3, hohenberg2022cyclinbcdk1and pages 2-3)
Subcellular localization	DENR acts predominantly in the cytoplasmic translation machinery on ribosome-associated complexes. Under oxidative stress, DENR relocalizes with MCT-1/MCTS1, eIF2D, ABCE1, eRF1, and eRF3 to cytoplasmic stress granules, suggesting spatial regulation of post-termination/reinitiation factors during stress and recovery. (makeeva2023relocalizationoftranslation pages 1-2)	(makeeva2023relocalizationoftranslation pages 1-2)
Key biological pathways	DENR functions in uORF-mediated translational control and contributes to selective translation in several pathways: stress-responsive ATF4 regulation within the integrated stress response; cell-cycle/mitotic translational control of mRNAs needed for faithful mitosis; and immune signaling through selective translation of JAK2 required for IL-23-dependent IFN-γ production in antimycobacterial immunity. Transcriptome-wide work indicates DENR affects only a subset of uORF-containing mRNAs, not global uORF control. (hohenberg2022cyclinbcdk1and pages 1-2, wek2023survivingandadapting pages 1-2, bohlen2023humanmcts1dependenttranslation pages 5-6, meurs2025mcts2anddistinct pages 2-3)	(hohenberg2022cyclinbcdk1and pages 1-2, wek2023survivingandadapting pages 1-2, bohlen2023humanmcts1dependenttranslation pages 5-6, meurs2025mcts2anddistinct pages 2-3)
Regulation mechanisms	DENR is regulated post-translationally during the cell cycle: Cyclin B/CDK1 and Cyclin A/CDK2 phosphorylate DENR at Ser73 at mitotic entry, phosphorylation peaks in early mitosis, promotes DENR stability, prevents cleavage at Asp26, and enhances translation of mitotic target mRNAs. In mitosis, about 40% of mRNAs with elevated translation were reported to be DENR targets, linking DENR regulation directly to phase-specific translational control. (hohenberg2022cyclinbcdk1and pages 1-2, hohenberg2022cyclinbcdk1and pages 2-3)	(hohenberg2022cyclinbcdk1and pages 1-2, hohenberg2022cyclinbcdk1and pages 2-3)
Disease relevance	DENR dysregulation is relevant to neurodevelopment, cancer, immunity, and neurodegeneration-linked non-canonical translation. Loss-of-function mutations in DENR are associated with impaired neurocortical migration and developmental brain disorders; DENR and MCTS1 have been described as oncogenic/pro-proliferative in several tumor contexts; DENR-dependent selective translation intersects with ATF4 stress signaling and JAK2-dependent IFN-γ immunity; and DENR knockdown suppresses repeat-associated non-AUG translation in models of repeat-expansion neurodegeneration. (hohenberg2022cyclinbcdk1and pages 1-2, green2022noncanonicalinitiationfactors pages 1-2, bohlen2023humanmcts1dependenttranslation pages 5-6)	(hohenberg2022cyclinbcdk1and pages 1-2, green2022noncanonicalinitiationfactors pages 1-2, bohlen2023humanmcts1dependenttranslation pages 5-6)

Table: This table summarizes the verified molecular function, mechanism, localization, regulatory biology, and disease relevance of human DENR. It condenses the most useful findings from recent and foundational sources into a citation-linked reference for annotation work.

Conclusions

DENR is a non-canonical translation factor with highly specific roles in ribosome recycling and reinitiation after uORF translation. Its primary molecular function is to remove deacylated tRNA from post-termination 40S ribosomal subunits, enabling these subunits to resume scanning and reinitiate translation at downstream coding sequences (grove2024toinitiateor pages 2-4, young2022rebirthofthe pages 1-3, sherlock2023principlesmechanismsand pages 1-3, meurs2025mcts2anddistinct pages 2-3). DENR operates exclusively as part of the DENR·MCTS1 (or DENR·MCTS2) heterodimer and localizes to the cytoplasm where it acts on ribosome-bound mRNA complexes (makeeva2023relocalizationoftranslation pages 1-2, bohlen2023humanmcts1dependenttranslation pages 5-6, meurs2025mcts2anddistinct pages 2-3).

Rather than functioning as a global regulator, DENR selectively controls translation of a specific subset of uORF-containing mRNAs whose architecture and sequence features render them dependent on DENR-mediated recycling and reinitiation (meurs2025mcts2anddistinct pages 1-2, meurs2025mcts2anddistinct pages 2-3). Through this selective mechanism, DENR participates in critical biological pathways including the integrated stress response (via ATF4), cell cycle-dependent mitotic translation, and immune signaling required for antimycobacterial immunity (via JAK2) (bohlen2023humanmcts1dependenttranslation pages 1-3, hohenberg2022cyclinbcdk1and pages 1-2, wek2023survivingandadapting pages 1-2, bohlen2023humanmcts1dependenttranslation pages 5-6).

The regulation of DENR by cell cycle kinases (CDK1/CDK2) through Ser73 phosphorylation demonstrates dynamic control of its activity and stability, linking cell cycle progression to translational programs (hohenberg2022cyclinbcdk1and pages 1-2, hohenberg2022cyclinbcdk1and pages 2-3). The clinical importance of DENR is underscored by human genetic evidence showing that MCTS1 deficiency (which destabilizes DENR) causes isolated mycobacterial disease through impaired JAK2 translation, and by associations between DENR dysfunction and neurodevelopmental disorders (bohlen2023humanmcts1dependenttranslation pages 1-3, hohenberg2022cyclinbcdk1and pages 1-2, bohlen2023humanmcts1dependenttranslation pages 5-6).

This research is based on recent authoritative sources from 2022-2026, including comprehensive reviews and primary research articles that employed state-of-the-art techniques such as ribosome profiling, cryo-EM structural studies, and genetic studies in model organisms and human patients.

References

(bohlen2023humanmcts1dependenttranslation pages 1-3): Jonathan Bohlen, Qinhua Zhou, Quentin Philippot, Masato Ogishi, Darawan Rinchai, Tea Nieminen, Simin Seyedpour, Nima Parvaneh, Nima Rezaei, Niloufar Yazdanpanah, Mana Momenilandi, Clément Conil, Anna-Lena Neehus, Carltin Schmidt, Carlos A. Arango-Franco, Tom Le Voyer, Taushif Khan, Rui Yang, Julia Puchan, Lucia Erazo, Mykola Roiuk, Taja Vatovec, Zarah Janda, Ivan Bagarić, Marie Materna, Adrian Gervais, Hailun Li, Jérémie Rosain, Jessica N Peel, Yoann Seeleuthner, Ji Eun Han, Anne-Sophie L’Honneur, Marcela Moncada-Vélez, Marta Martin-Fernandez, Michael E. Horesh, Tatiana Kochetkov, Monika Schmidt, Mohammed A. AlShehri, Eeva Salo, Harri Saxen, Gehad ElGhazali, Ahmad Yatim, Camille Soudée, Federica Sallusto, Armin Ensser, Nico Marr, Peng Zhang, Dusan Bogunovic, Aurélie Cobat, Mohammad Shahrooei, Vivien Béziat, Laurent Abel, Xiaochuan Wang, Stéphanie Boisson-Dupuis, Aurelio A. Teleman, Jacinta Bustamante, Qian Zhang, and Jean-Laurent Casanova. Human mcts1-dependent translation of jak2 is essential for ifn-γ immunity to mycobacteria. Cell, 186:5114-5134.e27, Nov 2023. URL: https://doi.org/10.1016/j.cell.2023.09.024, doi:10.1016/j.cell.2023.09.024. This article has 45 citations and is from a highest quality peer-reviewed journal.
(grove2024toinitiateor pages 2-4): Daisy J. Grove, Paul J. Russell, and Michael G. Kearse. To initiate or not to initiate: a critical assessment of eif2a, eif2d, and mct-1·denr to deliver initiator trna to ribosomes. Wiley interdisciplinary reviews. RNA, 15:e1833-e1833, Jul 2024. URL: https://doi.org/10.1002/wrna.1833, doi:10.1002/wrna.1833. This article has 21 citations and is from a peer-reviewed journal.
(grove2024toinitiateor pages 1-2): Daisy J. Grove, Paul J. Russell, and Michael G. Kearse. To initiate or not to initiate: a critical assessment of eif2a, eif2d, and mct-1·denr to deliver initiator trna to ribosomes. Wiley interdisciplinary reviews. RNA, 15:e1833-e1833, Jul 2024. URL: https://doi.org/10.1002/wrna.1833, doi:10.1002/wrna.1833. This article has 21 citations and is from a peer-reviewed journal.
(hohenberg2022cyclinbcdk1and pages 1-2): Katharina Clemm von Hohenberg, Sandra Müller, Sibylle Schleich, Matthias Meister, Jonathan Bohlen, Thomas G. Hofmann, and Aurelio A. Teleman. Cyclin b/cdk1 and cyclin a/cdk2 phosphorylate denr to promote mitotic protein translation and faithful cell division. Nature Communications, Feb 2022. URL: https://doi.org/10.1038/s41467-022-28265-0, doi:10.1038/s41467-022-28265-0. This article has 48 citations and is from a highest quality peer-reviewed journal.
(young2022rebirthofthe pages 1-3): David J. Young and Nicholas R. Guydosh. Rebirth of the translational machinery: the importance of recycling ribosomes. BioEssays, Feb 2022. URL: https://doi.org/10.1002/bies.202100269, doi:10.1002/bies.202100269. This article has 32 citations and is from a peer-reviewed journal.
(bohlen2023humanmcts1dependenttranslation pages 5-6): Jonathan Bohlen, Qinhua Zhou, Quentin Philippot, Masato Ogishi, Darawan Rinchai, Tea Nieminen, Simin Seyedpour, Nima Parvaneh, Nima Rezaei, Niloufar Yazdanpanah, Mana Momenilandi, Clément Conil, Anna-Lena Neehus, Carltin Schmidt, Carlos A. Arango-Franco, Tom Le Voyer, Taushif Khan, Rui Yang, Julia Puchan, Lucia Erazo, Mykola Roiuk, Taja Vatovec, Zarah Janda, Ivan Bagarić, Marie Materna, Adrian Gervais, Hailun Li, Jérémie Rosain, Jessica N Peel, Yoann Seeleuthner, Ji Eun Han, Anne-Sophie L’Honneur, Marcela Moncada-Vélez, Marta Martin-Fernandez, Michael E. Horesh, Tatiana Kochetkov, Monika Schmidt, Mohammed A. AlShehri, Eeva Salo, Harri Saxen, Gehad ElGhazali, Ahmad Yatim, Camille Soudée, Federica Sallusto, Armin Ensser, Nico Marr, Peng Zhang, Dusan Bogunovic, Aurélie Cobat, Mohammad Shahrooei, Vivien Béziat, Laurent Abel, Xiaochuan Wang, Stéphanie Boisson-Dupuis, Aurelio A. Teleman, Jacinta Bustamante, Qian Zhang, and Jean-Laurent Casanova. Human mcts1-dependent translation of jak2 is essential for ifn-γ immunity to mycobacteria. Cell, 186:5114-5134.e27, Nov 2023. URL: https://doi.org/10.1016/j.cell.2023.09.024, doi:10.1016/j.cell.2023.09.024. This article has 45 citations and is from a highest quality peer-reviewed journal.
(sherlock2023principlesmechanismsand pages 1-3): Madeline E. Sherlock, Laura Baquero Galvis, Quentin Vicens, Jeffrey S. Kieft, and Sujatha Jagannathan. Principles, mechanisms, and biological implications of translation termination–reinitiation. RNA, 29:865-884, Apr 2023. URL: https://doi.org/10.1261/rna.079375.122, doi:10.1261/rna.079375.122. This article has 43 citations and is from a domain leading peer-reviewed journal.
(jendruchova2024differentialeffectsof pages 1-2): Kristína Jendruchová, Swati Gaikwad, Kristýna Poncová, Stanislava Gunišová, Leoš Shivaya Valášek, and Alan G. Hinnebusch. Differential effects of 40s ribosome recycling factors on reinitiation at regulatory uorfs in gcn4 mrna are not dictated by their roles in bulk 40s recycling. Communications Biology, Sep 2024. URL: https://doi.org/10.1038/s42003-024-06761-x, doi:10.1038/s42003-024-06761-x. This article has 3 citations and is from a peer-reviewed journal.
(meurs2025mcts2anddistinct pages 1-2): Romane Meurs, Mara De Matos, Adrian Bothe, Nicolas Guex, Tobias Weber, Aurelio A Teleman, Nenad Ban, and David Gatfield. Mcts2 and distinct eif2d roles in uorf-dependent translation regulation revealed by in vitro re-initiation assays. The EMBO Journal, 44:854-876, Jan 2025. URL: https://doi.org/10.1038/s44318-024-00347-3, doi:10.1038/s44318-024-00347-3. This article has 3 citations.
(meurs2025mcts2anddistinct pages 2-3): Romane Meurs, Mara De Matos, Adrian Bothe, Nicolas Guex, Tobias Weber, Aurelio A Teleman, Nenad Ban, and David Gatfield. Mcts2 and distinct eif2d roles in uorf-dependent translation regulation revealed by in vitro re-initiation assays. The EMBO Journal, 44:854-876, Jan 2025. URL: https://doi.org/10.1038/s44318-024-00347-3, doi:10.1038/s44318-024-00347-3. This article has 3 citations.
(makeeva2023relocalizationoftranslation pages 1-2): Desislava S. Makeeva, Claire L. Riggs, Anton V. Burakov, Pavel A. Ivanov, Artem S. Kushchenko, Dmitri A. Bykov, Vladimir I. Popenko, Vladimir S. Prassolov, Pavel V. Ivanov, and Sergey E. Dmitriev. Relocalization of translation termination and ribosome recycling factors to stress granules coincides with elevated stop-codon readthrough and reinitiation rates upon oxidative stress. Cells, 12:259, Jan 2023. URL: https://doi.org/10.3390/cells12020259, doi:10.3390/cells12020259. This article has 16 citations.
(wek2023survivingandadapting pages 1-2): Ronald C. Wek, Tracy G. Anthony, and Kirk A. Staschke. Surviving and adapting to stress: translational control and the integrated stress response. Antioxidants & Redox Signaling, 39:351-373, Aug 2023. URL: https://doi.org/10.1089/ars.2022.0123, doi:10.1089/ars.2022.0123. This article has 95 citations and is from a domain leading peer-reviewed journal.
(hohenberg2022cyclinbcdk1and pages 2-3): Katharina Clemm von Hohenberg, Sandra Müller, Sibylle Schleich, Matthias Meister, Jonathan Bohlen, Thomas G. Hofmann, and Aurelio A. Teleman. Cyclin b/cdk1 and cyclin a/cdk2 phosphorylate denr to promote mitotic protein translation and faithful cell division. Nature Communications, Feb 2022. URL: https://doi.org/10.1038/s41467-022-28265-0, doi:10.1038/s41467-022-28265-0. This article has 48 citations and is from a highest quality peer-reviewed journal.
(green2022noncanonicalinitiationfactors pages 1-2): Katelyn M Green, Shannon L. Miller, Indranil Malik, and Peter K. Todd. Non-canonical initiation factors modulate repeat-associated non-aug translation. Human molecular genetics, 31:2521-2534, Feb 2022. URL: https://doi.org/10.1093/hmg/ddac021, doi:10.1093/hmg/ddac021. This article has 35 citations and is from a domain leading peer-reviewed journal.

Artifacts

Edison artifact artifact-00

Citations

jendruchova2024differentialeffectsof pages 1-2
makeeva2023relocalizationoftranslation pages 1-2
wek2023survivingandadapting pages 1-2
green2022noncanonicalinitiationfactors pages 1-2
grove2024toinitiateor pages 2-4
grove2024toinitiateor pages 1-2
young2022rebirthofthe pages 1-3
sherlock2023principlesmechanismsand pages 1-3
https://doi.org/10.1016/j.cell.2023.09.024,
https://doi.org/10.1002/wrna.1833,
https://doi.org/10.1038/s41467-022-28265-0,
https://doi.org/10.1002/bies.202100269,
https://doi.org/10.1261/rna.079375.122,
https://doi.org/10.1038/s42003-024-06761-x,
https://doi.org/10.1038/s44318-024-00347-3,
https://doi.org/10.3390/cells12020259,
https://doi.org/10.1089/ars.2022.0123,
https://doi.org/10.1093/hmg/ddac021,

📚 Additional Documentation

Notes

(DENR-notes.md)

DENR (Density-regulated protein, DRP) — research notes

UniProt O43583. 198 aa. Contains a C-terminal SUI1 domain (eIF1-like). Member of the DENR family; homologous to the C-terminal region of Ligatin/eIF2D, while MCTS1 is homologous to the N-terminal region.

Core function

DENR forms a heterodimer with MCTS1; the MCTS1–DENR complex is a non-canonical translation (re)initiation and 40S recycling factor. It is the functional equivalent of eIF2D split into two polypeptides.

PMID:20713520
PMID:20713520
UniProt FUNCTION: "Translation regulator forming a complex with MCTS1 to promote translation reinitiation ... Firstly, the dissociation of deacylated tRNAs from post-termination 40S ribosomal complexes during ribosome recycling. Secondly, the recruitment in an EIF2-independent manner of aminoacylated initiator tRNA to P site of 40S ribosomes for a new round of translation."
DENR–MCTS1 heterodimerization and tRNA recruitment are required for translation reinitiation [PMID:29889857 title]. DENR contributes the SUI1 (PUA-interacting) module; MCTS1 PUA domain binds DENR.
MCTS1-dependent reinitiation translates specific mRNAs incl. JAK2; essential for IFN-γ immunity [PMID:37875108 title].

Interactions (IPI)

MCTS1 (Q9ULC4): the physiological obligate partner — many entries (16169070, 21516116, 32296183, 33961781, 40205054, 16982740). Best captured as MCTS1 binding / heterodimerization, not bare protein binding.
MAPT (P10636, tau), MARCHF5 (Q9NX47), NELFB/UBC: high-throughput, peripheral.

Localization

Cytoplasm (IDA, PMID:16982740). Also reported in stress granules / nucleolus (CD-CODE) but cytoplasmic ribosome-associated is the functional site.

Decisions

Reinitiation, preinitiation complex formation, ribosome disassembly (recycling), eIF2-independent tRNA delivery = core.
MF: translation initiation factor activity (GO:0003743) is supported (eIF2D-like). Core MF.
protein binding IPI with MCTS1 → MODIFY to protein heterodimerization/MCTS1 binding context; non-MCTS1 ones KEEP_AS_NON_CORE or over-annotated.
IRES-dependent viral translational initiation (GO:0075522) — supported by 20713520 (HCV-like IRES P-site delivery). KEEP_AS_NON_CORE.

Pn Notes

(DENR-pn-notes.md)

DENR PN Consistency Notes

Generated: 2026-06-18
Project: PROTEOSTASIS
Scope: PN consistency rereview against local AIGR review and available deep-research artifacts
UniProt: O43583
AIGR review status: COMPLETE
Review batch: proteostasis-batch-2026-06-07c
Batch change status: added

Source Files Checked

AIGR review YAML: present - genes/human/DENR/DENR-ai-review.yaml
AIGR review HTML: present - genes/human/DENR/DENR-ai-review.html
Gene notes: present - genes/human/DENR/DENR-notes.md
GOA TSV: present - genes/human/DENR/DENR-goa.tsv
UniProt record: present - genes/human/DENR/DENR-uniprot.txt
PN dossier: projects/PROTEOSTASIS/reports/phase1_dossiers/DENR.md
PN consistency section: projects/PROTEOSTASIS/reports/phase1_dossiers/_sections/DENR.md
PN projection report: projects/PROTEOSTASIS/reports/pn_projection/pn_projected_gene_go_summary.tsv
PN mapping audit: projects/PROTEOSTASIS/reports/pn_mapping_audit/current_mapping_scrutiny.tsv

Deep Research Files

No *-deep-research*.md file found in this gene directory.

AIGR Review Snapshot

Description: DENR (Density-regulated protein, DRP) is a small cytoplasmic protein containing a C-terminal SUI1 (eIF1-like) domain. Together with its obligate partner MCTS1 it forms the MCTS1-DENR heterodimer, a non-canonical translation factor that is the functional equivalent of eIF2D (Ligatin) split into two polypeptides (MCTS1 corresponds to the N-terminal half, DENR to the C-terminal SUI1 half of Ligatin). The complex acts at the post-termination 40S ribosome to promote translation reinitiation, particularly after translation of short upstream ORFs (uORFs), enabling the small subunit to resume scanning and initiate at a downstream main ORF. Mechanistically the complex (i) promotes dissociation of deacylated tRNA and mRNA from recycled 40S subunits following ABCE1-mediated splitting of post-termination complexes, and (ii) recruits aminoacylated initiator tRNA into the ribosomal P-site in an eIF2-independent manner when the start codon is already positioned in the P-site (as on certain HCV-like IRESs and reinitiation events). This activity governs the translation of a defined set of mRNAs (including JAK2), and MCTS1-DENR-dependent reinitiation is required for IFN-gamma immunity.
Existing/core annotation action counts: ACCEPT: 9; KEEP_AS_NON_CORE: 13

PN Consistency Summary

Consistency: Internal review/notes are self-consistent and accurate: DENR is the SUI1 half of the MCTS1-DENR heterodimer (eIF2D split), a reinitiation / 40S-recycling factor. But this CONTRADICTS the PN placement under "Translation termination" and the projected GO:0006415. DENR is not a release factor and does no peptide release.
PN story / NEW pressure: Dossier projects GO:0006415 translational termination as new_to_goa. Verified (OLS): GO:0006415 = "release of a polypeptide chain from the ribosome ... in response to a termination codon" — i.e. eRF1/eRF3 activity, NOT DENR's. DENR's true process, GO:0002188 translation reinitiation, is already in GOA (IBA + IDA PMID:37875108) and accepted as core in the review; GO:0001731 and GO:0032790 (recycling) are also present. So the PN node mis-assigns DENR to termination; the real function is already captured. The projected term over-reaches / is biologically wrong for this gene.
Evidence alignment: Dossier row carries no reference titles; review evidence (PMID:20713520 recycling, PMID:29889857 heterodimer, PMID:37875108 JAK2/IFN-γ) is rich and verified — no overlap to compare, divergence is by omission in the dossier.
Verdict: Mapping mismatch — PN "translation termination" + GO:0006415 contradicts DENR's reinitiation/recycling biology (already in GOA as GO:0002188). Recommended edits: [MAP] do not project GO:0006415 to DENR; reclassify the PN node as translation reinitiation/40S recycling (GO:0002188 already in GOA).

Full Consistency Review

UniProt: O43583 · batch: proteostasis-batch-2026-06-07c · review status: COMPLETE
PN placement: Translation|Cytosolic translation|Translation termination|tRNA, mRNA release ; PN-node mapping: group Translation termination → GO:0006415 translational termination (mapped, ok_for_propagation); type tRNA, mRNA release no_mapping.
Consistency: Internal review/notes are self-consistent and accurate: DENR is the SUI1 half of the MCTS1-DENR heterodimer (eIF2D split), a reinitiation / 40S-recycling factor. But this CONTRADICTS the PN placement under "Translation termination" and the projected GO:0006415. DENR is not a release factor and does no peptide release.
PN story / NEW pressure: Dossier projects GO:0006415 translational termination as new_to_goa. Verified (OLS): GO:0006415 = "release of a polypeptide chain from the ribosome ... in response to a termination codon" — i.e. eRF1/eRF3 activity, NOT DENR's. DENR's true process, GO:0002188 translation reinitiation, is already in GOA (IBA + IDA PMID:37875108) and accepted as core in the review; GO:0001731 and GO:0032790 (recycling) are also present. So the PN node mis-assigns DENR to termination; the real function is already captured. The projected term over-reaches / is biologically wrong for this gene.
Mapping strategy: This gene argues the Translation termination|tRNA, mRNA release node mixes genuine release factors with post-termination recycling/reinitiation factors (DENR, EIF2D). Recommend re-placing DENR (and EIF2D) under a reinitiation/recycling node, or at minimum not propagating GO:0006415 to them.
Evidence alignment: Dossier row carries no reference titles; review evidence (PMID:20713520 recycling, PMID:29889857 heterodimer, PMID:37875108 JAK2/IFN-γ) is rich and verified — no overlap to compare, divergence is by omission in the dossier.
Verdict: Mapping mismatch — PN "translation termination" + GO:0006415 contradicts DENR's reinitiation/recycling biology (already in GOA as GO:0002188). Recommended edits: [MAP] do not project GO:0006415 to DENR; reclassify the PN node as translation reinitiation/40S recycling (GO:0002188 already in GOA).

PN Dossier Context

review_batch: proteostasis-batch-2026-06-07c
review_yaml: genes/human/DENR/DENR-ai-review.yaml
PN workbook rows: 1

PN row 1: Translation | Cytosolic translation | Translation termination | tRNA, mRNA release

UniProt: O43583
In branches: TR
PN-node mapping records (path + ancestors):
- [type] Translation|Cytosolic translation|Translation termination|tRNA, mRNA release
  status=no_mapping scope= GO=[]
  rationale: Reviewed as a broad PN category rather than a single GO class. The member genes span multiple activities, complexes, or contexts, so direct propagation from this node would overstate the shared biology.
- [group] Translation|Cytosolic translation|Translation termination
  status=mapped scope=ok_for_propagation_to_go GO=[GO:0006415 translational termination]
  rationale: This PN group denotes cytosolic translation termination and release factors. Translational termination is the shared process target.
- [class] Translation|Cytosolic translation
  status=context_only scope=too_broad_to_propagate GO=[GO:0002181 cytoplasmic translation]
  rationale: The PN class Cytosolic translation is centered on the cytoplasmic translation apparatus and process, but it also houses supporting machinery such as ribosome biogenesis factors. The GO process term is a useful high-level label for the class, but propagating it to all members would over-annotate genes whose PN placement is through assembly or maturation context rather than core cytoplasmic translation.
- [branch] Translation
  status=context_only scope=too_broad_to_propagate GO=[GO:0006412 translation]
  rationale: The PN Translation branch is organized around the translation apparatus and immediately associated cotranslational quality-control systems. GO translation is the closest high-level process label, but the PN branch also contains adjacent machinery such as ribosome biogenesis and nascent-chain handling. Keeping this relationship is useful for interpretation, but it is too broad to project safely onto every member.

Projected GO annotations (1)

GO:0006415 translational termination | scope=ok_for_propagation_to_go | goa_status=new_to_goa | from=Translation|Cytosolic translation|Translation termination

Note

This file is generated from the current PROTEOSTASIS phase-1 dossier and local gene-review artifacts. Edit the source review, PN mapping, or dossier rather than this generated note when correcting the underlying curation.

📄 View Raw YAML

id: O43583
gene_symbol: DENR
product_type: PROTEIN
status: COMPLETE
taxon:
  id: NCBITaxon:9606
  label: Homo sapiens
description: DENR (Density-regulated protein, DRP) is a small cytoplasmic protein containing a C-terminal SUI1 (eIF1-like) domain. Together with its obligate partner MCTS1 it forms the MCTS1-DENR heterodimer, a non-canonical translation factor that is the functional equivalent of eIF2D (Ligatin) split into two polypeptides (MCTS1 corresponds to the N-terminal half, DENR to the C-terminal SUI1 half of Ligatin). The complex acts at the post-termination 40S ribosome to promote translation reinitiation, particularly after translation of short upstream ORFs (uORFs), enabling the small subunit to resume scanning and initiate at a downstream main ORF. Mechanistically the complex (i) promotes dissociation of deacylated tRNA and mRNA from recycled 40S subunits following ABCE1-mediated splitting of post-termination complexes, and (ii) recruits aminoacylated initiator tRNA into the ribosomal P-site in an eIF2-independent manner when the start codon is already positioned in the P-site (as on certain HCV-like IRESs and reinitiation events). This activity governs the translation of a defined set of mRNAs (including JAK2), and MCTS1-DENR-dependent reinitiation is required for IFN-gamma immunity.
existing_annotations:
- term:
    id: GO:0001731
    label: formation of translation preinitiation complex
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: involved_in
  review:
    summary: Phylogenetic transfer of preinitiation-complex formation, consistent with the experimentally documented role of the MCTS1-DENR complex in assembling tRNA onto 40S/mRNA complexes for (re)initiation.
    action: ACCEPT
    reason: The IBA is corroborated by direct experimental evidence that MCTS1/DENR promotes recruitment of initiator tRNA to 40S/mRNA complexes when the start codon is in the P-site.
    supported_by:
    - reference_id: file:human/DENR/DENR-uniprot.txt
      supporting_text: the recruitment in an EIF2-independent manner of aminoacylated initiator tRNA to P site of 40S ribosomes for a new round of translation
- term:
    id: GO:0002188
    label: translation reinitiation
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: involved_in
  review:
    summary: Translation reinitiation is the central, defining biological process of DENR, acting in the MCTS1-DENR complex after short uORFs to allow reinitiation at a downstream ORF. Reinitiation is selective for a subset of uORF-containing transcripts (not global uORF control), and DENR is functionally distinct from its single-chain homolog eIF2D.
    action: ACCEPT
    reason: Strongly supported by both phylogenetic inference and direct experimental evidence (UniProt FUNCTION; ComplexPortal IDA), and is core to DENR function. Recent review/biochemical literature synthesized in the falcon deep research reinforces the uORF-selective reinitiation role of the DENR-MCTS1 complex.
    supported_by:
    - reference_id: file:human/DENR/DENR-uniprot.txt
      supporting_text: Translation regulator forming a complex with MCTS1 to promote translation reinitiation.
    - reference_id: file:human/DENR/DENR-deep-research-falcon.md
      supporting_text: DENR enables post-termination 40S subunits to resume scanning and initiate translation at downstream start codons, most critically at the main ORF of the mRNA
- term:
    id: GO:0002183
    label: cytoplasmic translational initiation
  evidence_type: IEA
  original_reference_id: GO_REF:0000117
  qualifier: involved_in
  review:
    summary: Automated (ARBA) assignment of cytoplasmic translational initiation. DENR does participate in cytoplasmic (re)initiation, but its specific role is non-canonical reinitiation/recycling rather than canonical initiation.
    action: KEEP_AS_NON_CORE
    reason: Broadly correct compartment and process, but more general than DENR's specific reinitiation/recycling role; retained as non-core.
    supported_by:
    - reference_id: file:human/DENR/DENR-uniprot.txt
      supporting_text: the recruitment in an EIF2-independent manner of aminoacylated initiator tRNA to P site of 40S ribosomes for a new round of translation
- term:
    id: GO:0003743
    label: translation initiation factor activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000002
  qualifier: enables
  review:
    summary: InterPro/SUI1-domain-based assignment of translation initiation factor activity. DENR contributes the SUI1 module of the MCTS1-DENR complex that delivers tRNA to the 40S P-site, so this molecular function is appropriate.
    action: ACCEPT
    reason: The eIF2D-like (re)initiation-factor activity is experimentally established for the MCTS1-DENR complex; DENR is an essential subunit. This is a core molecular function.
    supported_by:
    - reference_id: file:human/DENR/DENR-uniprot.txt
      supporting_text: the recruitment in an EIF2-independent manner of aminoacylated initiator tRNA to P site of 40S ribosomes for a new round of translation
- term:
    id: GO:0005737
    label: cytoplasm
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  qualifier: located_in
  review:
    summary: Automated cytoplasmic localization, consistent with the experimentally determined cytoplasmic site of action.
    action: ACCEPT
    reason: Agrees with IDA cytoplasm evidence (PMID:16982740); DENR acts on cytoplasmic ribosomes.
    supported_by:
    - reference_id: file:human/DENR/DENR-uniprot.txt
      supporting_text: 'SUBCELLULAR LOCATION: Cytoplasm'
- term:
    id: GO:0006413
    label: translational initiation
  evidence_type: IEA
  original_reference_id: GO_REF:0000002
  qualifier: involved_in
  review:
    summary: General translational initiation, assigned from the SUI1 domain. DENR's specific role is non-canonical reinitiation and recycling rather than canonical cap-dependent initiation.
    action: KEEP_AS_NON_CORE
    reason: Correct parent process but less informative than the specific reinitiation role; retained as non-core.
    supported_by:
    - reference_id: file:human/DENR/DENR-uniprot.txt
      supporting_text: Translation regulator forming a complex with MCTS1 to promote translation reinitiation.
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:16169070
  qualifier: enables
  review:
    summary: IntAct interaction with MCTS1 (Q9ULC4), DENR's obligate functional partner. The bare protein binding term is uninformative, but the interaction itself is central to DENR function as part of the MCTS1-DENR heterodimer.
    action: KEEP_AS_NON_CORE
    reason: Records a real and functionally pivotal MCTS1 interaction; per curation guidelines bare protein binding is not elevated to core, but the heterodimerization is captured in core_functions.
    supported_by:
    - reference_id: file:human/DENR/DENR-goa.tsv
      supporting_text: GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:16169070 UniProtKB:Q9ULC4
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:16874301
  qualifier: enables
  review:
    summary: IntAct interactions with UBC (P0CG48) and MARCHF5 (Q9NX47) from a high-throughput screen, unrelated to DENR's reinitiation function.
    action: KEEP_AS_NON_CORE
    reason: Bare protein binding from high-throughput screens with partners not connected to the MCTS1-DENR reinitiation/recycling function; uninformative and non-core.
    supported_by:
    - reference_id: file:human/DENR/DENR-goa.tsv
      supporting_text: GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:16874301 UniProtKB:Q9NX47
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:16936636
  qualifier: enables
  review:
    summary: IntAct interactions with UBC (P0CG48) and MARCHF5 (Q9NX47); high-throughput, not connected to DENR's translation function.
    action: KEEP_AS_NON_CORE
    reason: Bare protein binding from high-throughput screens with partners unrelated to reinitiation; uninformative and non-core.
    supported_by:
    - reference_id: file:human/DENR/DENR-goa.tsv
      supporting_text: GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:16936636 UniProtKB:Q9NX47
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:20195357
  qualifier: enables
  review:
    summary: IntAct interaction with NELFB (Q8WX92) from a high-throughput screen; not related to DENR's reinitiation/recycling function.
    action: KEEP_AS_NON_CORE
    reason: Bare protein binding from a high-throughput screen with a partner unrelated to DENR's core function; uninformative.
    supported_by:
    - reference_id: file:human/DENR/DENR-goa.tsv
      supporting_text: GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:20195357 UniProtKB:Q8WX92
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:21516116
  qualifier: enables
  review:
    summary: IntAct interaction with MCTS1 (Q9ULC4), the obligate DENR partner.
    action: KEEP_AS_NON_CORE
    reason: Records the functionally central MCTS1 interaction; bare protein binding is not elevated to core but the heterodimer is captured in core_functions.
    supported_by:
    - reference_id: file:human/DENR/DENR-goa.tsv
      supporting_text: GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:21516116 UniProtKB:Q9ULC4
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:32296183
  qualifier: enables
  review:
    summary: IntAct interaction with MCTS1 (Q9ULC4), the obligate DENR partner.
    action: KEEP_AS_NON_CORE
    reason: Records the functionally central MCTS1 interaction; bare protein binding is not elevated to core but the heterodimer is captured in core_functions.
    supported_by:
    - reference_id: file:human/DENR/DENR-goa.tsv
      supporting_text: GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:32296183 UniProtKB:Q9ULC4
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:33961781
  qualifier: enables
  review:
    summary: BioPlex interactions including MCTS1 (Q9ULC4) and MAPT/tau (P10636). The MCTS1 interaction is functionally central; the tau interaction is a high-throughput observation.
    action: KEEP_AS_NON_CORE
    reason: Captures the functionally central MCTS1 interaction (alongside a peripheral tau hit); bare protein binding is not elevated to core.
    supported_by:
    - reference_id: file:human/DENR/DENR-goa.tsv
      supporting_text: GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:33961781 UniProtKB:Q9ULC4
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:34757590
  qualifier: enables
  review:
    summary: IntAct interaction with MAPT/tau (P10636) from a high-throughput study; not connected to DENR's reinitiation function.
    action: KEEP_AS_NON_CORE
    reason: Bare protein binding from a high-throughput screen with tau, unrelated to DENR's core function; uninformative.
    supported_by:
    - reference_id: file:human/DENR/DENR-goa.tsv
      supporting_text: GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:34757590 UniProtKB:P10636
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:40205054
  qualifier: enables
  review:
    summary: Cell-maps interactome interaction with MCTS1 (Q9ULC4), the obligate DENR partner.
    action: KEEP_AS_NON_CORE
    reason: Records the functionally central MCTS1 interaction; bare protein binding is not elevated to core but is captured in core_functions.
    supported_by:
    - reference_id: file:human/DENR/DENR-goa.tsv
      supporting_text: GO:0005515 protein binding molecular_function ECO:0000353 IPI PMID:40205054 UniProtKB:Q9ULC4
- term:
    id: GO:0002188
    label: translation reinitiation
  evidence_type: IDA
  original_reference_id: PMID:37875108
  qualifier: involved_in
  review:
    summary: Direct evidence (ComplexPortal/IDA) that the MCTS1-DENR complex mediates translation reinitiation, demonstrated for JAK2 and other targets.
    action: ACCEPT
    reason: Direct experimental support for the core reinitiation function of DENR within the MCTS1-DENR complex.
    supported_by:
    - reference_id: file:human/DENR/DENR-uniprot.txt
      supporting_text: Translation regulator forming a complex with MCTS1 to promote translation reinitiation.
- term:
    id: GO:0070992
    label: translation initiation complex
  evidence_type: IPI
  original_reference_id: PMID:29889857
  qualifier: part_of
  review:
    summary: DENR is part of the MCTS1-DENR (re)initiation complex; heterodimerization with MCTS1 and tRNA recruitment are required for reinitiation.
    action: ACCEPT
    reason: Supported by structural/biochemical demonstration that DENR-MCTS1 heterodimerize to form the functional reinitiation complex.
    supported_by:
    - reference_id: PMID:29889857
      supporting_text: DENR-MCTS1 heterodimerization and tRNA recruitment are required for translation reinitiation
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:16982740
  qualifier: enables
  review:
    summary: UniProt-curated interaction with MCTS1 (Q9ULC4); this is the foundational report that DENR/DRP is recruited by MCTS1 via the PUA/SUI1 interface.
    action: KEEP_AS_NON_CORE
    reason: Records the functionally central MCTS1 interaction; bare protein binding is not elevated to core but the heterodimer is captured in core_functions.
    supported_by:
    - reference_id: PMID:16982740
      supporting_text: recruits the density-regulated protein (DENR/DRP), containing the SUI1 translation initiation domain
- term:
    id: GO:0005737
    label: cytoplasm
  evidence_type: IDA
  original_reference_id: PMID:16982740
  qualifier: is_active_in
  review:
    summary: Direct evidence that DENR is active in the cytoplasm, where it associates with the cap complex/translation machinery via MCTS1.
    action: ACCEPT
    reason: IDA-supported cytoplasmic site of action, consistent with DENR's role on cytoplasmic ribosomes.
    supported_by:
    - reference_id: file:human/DENR/DENR-uniprot.txt
      supporting_text: 'SUBCELLULAR LOCATION: Cytoplasm'
- term:
    id: GO:0075522
    label: IRES-dependent viral translational initiation
  evidence_type: IDA
  original_reference_id: PMID:20713520
  qualifier: involved_in
  review:
    summary: MCT-1/DENR promotes eIF2-independent recruitment of initiator tRNA on HCV-like IRESs and SV 26S mRNA, where the start codon is placed directly in the P-site.
    action: KEEP_AS_NON_CORE
    reason: A genuine but specialized application of DENR's P-site tRNA delivery activity (viral IRES context); retained as non-core relative to cellular reinitiation.
    supported_by:
    - reference_id: PMID:20713520
      supporting_text: promote efficient eIF2-independent recruitment of Met-tRNA(Met)(i) to 40S/mRNA complexes, if attachment of 40S subunits to the mRNA places the initiation codon directly in the P site, as on HCV-like IRESs
- term:
    id: GO:0001731
    label: formation of translation preinitiation complex
  evidence_type: IDA
  original_reference_id: PMID:20713520
  qualifier: involved_in
  review:
    summary: Direct evidence that MCT-1/DENR assembles initiator tRNA onto 40S/mRNA complexes, forming a preinitiation-type complex for reinitiation/recycling.
    action: ACCEPT
    reason: Direct experimental support for DENR's role in assembling the tRNA-loaded 40S complex.
    supported_by:
    - reference_id: PMID:20713520
      supporting_text: promote efficient eIF2-independent recruitment of Met-tRNA(Met)(i) to 40S/mRNA complexes
- term:
    id: GO:0032790
    label: ribosome disassembly
  evidence_type: IDA
  original_reference_id: PMID:20713520
  qualifier: involved_in
  review:
    summary: MCT-1/DENR promotes release of deacylated tRNA and mRNA from recycled 40S subunits after ABCE1-mediated splitting of post-termination ribosomes, i.e. the recycling/recovery step. Recent reviews reinforce that this tRNA-release/40S-recycling activity (a property of the DENR-MCTS1 complex) is a defining function and that penultimate-codon identity in the uORF modulates the efficiency of DENR-MCTS1-dependent recycling.
    action: ACCEPT
    reason: Direct experimental support for DENR's role in 40S recycling (clearing deacylated tRNA/mRNA), a core part of its function, corroborated by recent review literature synthesized in the falcon deep research. Recycling is a property of the DENR-MCTS1 heterodimer, of which DENR is the essential SUI1-bearing subunit.
    supported_by:
    - reference_id: PMID:20713520
      supporting_text: Ligatin and MCT-1/DENR can promote release of deacylated tRNA and mRNA from recycled 40S subunits after ABCE1-mediated dissociation of post-termination ribosomes
    - reference_id: file:human/DENR/DENR-deep-research-falcon.md
      supporting_text: This tRNA release is essential for 40S ribosome dissociation from mRNA and recycling back into the translational pool
references:
- id: file:human/DENR/DENR-deep-research-falcon.md
  title: Falcon deep research report for DENR
  reference_review:
    relevance: HIGH
    correctness: UNVERIFIED
    review_notes: 'LLM-synthesized deep-research report (Edison/Falcon). DENR-specific claims
      that are well-anchored to the primary literature and consistent with the curated picture:
      DENR is a non-canonical translation factor acting only as part of the DENR-MCTS1 (or
      DENR-MCTS2) heterodimer; core activities are post-termination 40S recycling (release of
      deacylated tRNA from the P-site) and reinitiation after short uORFs; cytoplasmic, ribosome-associated
      localization with stress-granule relocalization under oxidative (arsenite) stress; cell-cycle
      regulation via Ser73 phosphorylation by Cyclin B/CDK1 and Cyclin A/CDK2. CAVEAT: the report
      frequently attributes the heterodimer''s biochemical activities to "DENR" alone; recycling/reinitiation/tRNA-handling
      are properties of the DENR-MCTS1 complex, of which DENR contributes the SUI1/eIF1-like half.
      Pathway/disease claims (ATF4/ISR, JAK2/IFN-gamma immunity, mitotic translation, RAN-translation
      suppression, neurodevelopment) are largely heterodimer- or MCTS1-centric inferences and not
      DENR-only molecular functions. Underlying PMIDs not individually verified here (report cites by
      internal keys, not PMIDs), hence UNVERIFIED.'
  findings:
  - statement: The DENR-MCTS1 complex acts on post-termination 40S ribosomal subunits to facilitate
      removal of deacylated tRNA from the P-site, which is essential for 40S dissociation from mRNA
      and recycling back into the translational pool.
    reference_section_type: OTHER
  - statement: DENR-MCTS1 promotes translation reinitiation, particularly after short uORFs in 5'UTRs,
      and this reinitiation is selective for only a subset of uORF-containing transcripts; DENR is functionally
      distinct from its single-chain homolog eIF2D.
    reference_section_type: OTHER
  - statement: Under oxidative (arsenite) stress, DENR relocalizes together with MCTS1, eIF2D, ABCE1,
      eRF1 and eRF3 to cytoplasmic stress granules, suggesting spatial regulation of post-termination/reinitiation
      factors during stress.
    reference_section_type: OTHER
- id: GO_REF:0000002
  title: Gene Ontology annotation through association of InterPro records with GO terms
  findings: []
- id: GO_REF:0000033
  title: Annotation inferences using phylogenetic trees
  findings: []
- id: GO_REF:0000044
  title: Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping
  findings: []
- id: GO_REF:0000117
  title: Electronic Gene Ontology annotations created by ARBA machine learning models
  findings: []
- id: PMID:16169070
  title: 'A human protein-protein interaction network: a resource for annotating the proteome.'
  findings: []
- id: PMID:16874301
  title: A novel mitochondrial ubiquitin ligase plays a critical role in mitochondrial dynamics.
  findings: []
- id: PMID:16936636
  title: MARCH-V is a novel mitofusin 2- and Drp1-binding protein able to change mitochondrial morphology.
  findings: []
- id: PMID:16982740
  title: MCT-1 protein interacts with the cap complex and modulates messenger RNA translational profiles.
  findings:
  - statement: MCT-1 (MCTS1) interacts with the cap complex through its PUA domain and recruits DENR/DRP, which contains the SUI1 translation initiation domain.
    reference_section_type: ABSTRACT
- id: PMID:20195357
  title: A comprehensive resource of interacting protein regions for refining human transcription factor networks.
  findings: []
- id: PMID:20713520
  title: Activities of Ligatin and MCT-1/DENR in eukaryotic translation initiation and ribosomal recycling.
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: Cached publication title matches; abstract establishes the eIF2-independent initiator-tRNA recruitment and 40S recycling activities of MCT-1/DENR, directly supporting DENR's core reinitiation/recycling function.
  findings:
  - statement: MCT-1 and DENR (homologous to N- and C-terminal regions of Ligatin) together promote eIF2-independent recruitment of initiator tRNA to 40S/mRNA complexes when the initiation codon is placed directly in the P-site.
    reference_section_type: ABSTRACT
  - statement: MCT-1/DENR can promote release of deacylated tRNA and mRNA from recycled 40S subunits after ABCE1-mediated dissociation of post-termination ribosomes.
    reference_section_type: ABSTRACT
- id: PMID:21516116
  title: Next-generation sequencing to generate interactome datasets.
  findings: []
- id: PMID:29889857
  title: DENR-MCTS1 heterodimerization and tRNA recruitment are required for translation reinitiation.
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: Cached publication title matches; establishes that DENR-MCTS1 heterodimerization and tRNA recruitment are required for translation reinitiation, directly supporting DENR's core function.
  findings:
  - statement: DENR and MCTS1 heterodimerize and this, together with tRNA recruitment, is required for translation reinitiation.
    reference_section_type: TITLE
- id: PMID:32296183
  title: A reference map of the human binary protein interactome.
  findings: []
- id: PMID:33961781
  title: Dual proteome-scale networks reveal cell-specific remodeling of the human interactome.
  findings: []
- id: PMID:34757590
  title: Targeting Tau Mitigates Mitochondrial Fragmentation and Oxidative Stress in Amyotrophic Lateral Sclerosis.
  findings: []
- id: PMID:37875108
  title: Human MCTS1-dependent translation of JAK2 is essential for IFN-γ immunity to mycobacteria.
  findings:
  - statement: MCTS1-DENR-dependent translation reinitiation is required for translation of JAK2 and for IFN-gamma immunity to mycobacteria.
    reference_section_type: ABSTRACT
- id: PMID:40205054
  title: Multimodal cell maps as a foundation for structural and functional genomics.
  findings: []
core_functions:
- description: As an essential subunit of the MCTS1-DENR heterodimer (an eIF2D-like non-canonical factor), provides the SUI1 module that delivers aminoacylated tRNA into the 40S ribosomal P-site in an eIF2-independent manner to drive translation reinitiation after short uORFs.
  molecular_function:
    id: GO:0003743
    label: translation initiation factor activity
  locations:
  - id: GO:0005737
    label: cytoplasm
  supported_by:
  - reference_id: file:human/DENR/DENR-uniprot.txt
    supporting_text: the recruitment in an EIF2-independent manner of aminoacylated initiator tRNA to P site of 40S ribosomes for a new round of translation
  - reference_id: PMID:29889857
    supporting_text: DENR-MCTS1 heterodimerization and tRNA recruitment are required for translation reinitiation
- description: Within the MCTS1-DENR complex, promotes recycling/recovery of post-termination 40S subunits by promoting dissociation of deacylated tRNA and mRNA after ABCE1-mediated ribosome splitting.
  molecular_function:
    id: GO:0003743
    label: translation initiation factor activity
  locations:
  - id: GO:0005737
    label: cytoplasm
  supported_by:
  - reference_id: PMID:20713520
    supporting_text: Ligatin and MCT-1/DENR can promote release of deacylated tRNA and mRNA from recycled 40S subunits after ABCE1-mediated dissociation of post-termination ribosomes
  - reference_id: file:human/DENR/DENR-deep-research-falcon.md
    supporting_text: to facilitate the removal of deacylated tRNA from the ribosomal P-site
proposed_new_terms: []
suggested_questions:
- question: What determines the subset of >150 mRNAs whose reinitiation depends on MCTS1-DENR, and do uORF features (length, Kozak context, terminator distance) predict dependence?
- question: Does phosphorylation of DENR (Ser-73 and other mitotic sites) regulate MCTS1-DENR complex assembly or reinitiation activity?
- question: To what extent can the MCTS1 paralog MCTS2 substitute for MCTS1 as a DENR partner in vivo, and does DENR-MCTS2 have distinct transcript selectivity from DENR-MCTS1?
suggested_experiments:
- description: Ribosome profiling in DENR-knockout versus wild-type cells to map reinitiation-dependent mORFs genome-wide and define uORF determinants of MCTS1-DENR dependence.
- description: Reconstituted 40S recycling assays with purified DENR/MCTS1, ABCE1 and post-termination complexes to quantify the kinetics of deacylated tRNA/mRNA release contributed by DENR.

DENR

Gene Description

Existing Annotations Review

Core Functions

As an essential subunit of the MCTS1-DENR heterodimer (an eIF2D-like non-canonical factor), provides the SUI1 module that delivers aminoacylated tRNA into the 40S ribosomal P-site in an eIF2-independent manner to drive translation reinitiation after short uORFs.

Within the MCTS1-DENR complex, promotes recycling/recovery of post-termination 40S subunits by promoting dissociation of deacylated tRNA and mRNA after ABCE1-mediated ribosome splitting.

References

Suggested Questions for Experts

Suggested Experiments

Deep Research

Falcon

Comprehensive Research Report on DENR (Density-Regulated Protein)

Gene and Protein Identity Verification

Primary Molecular Function

1. Ribosome Recycling

2. Translation Reinitiation

Biochemical Mechanism and Substrate Specificity

Substrate Specificity

Subcellular Localization

Biological Pathways and Processes

1. Integrated Stress Response (ISR)

2. Cell Cycle and Mitotic Translational Control

3. Immune Signaling and Antimycobacterial Immunity

4. Neurological Function and Development

Protein Interactions and Regulatory Partners

MCTS1 (Primary Partner)

MCTS2 (Alternative Partner)

Ribosome and tRNA Interactions

Regulatory Kinases

Relationship to eIF2D

Summary Table

Conclusions

Artifacts

Citations

📚 Additional Documentation

Notes

DENR (Density-regulated protein, DRP) — research notes

Core function

Interactions (IPI)

Localization

Decisions

Pn Notes

DENR PN Consistency Notes

Source Files Checked

Deep Research Files

AIGR Review Snapshot

PN Consistency Summary

Full Consistency Review

PN Dossier Context

PN row 1: Translation | Cytosolic translation | Translation termination | tRNA, mRNA release

Projected GO annotations (1)

Note

📄 View Raw YAML