| 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. (pqac-00000001, pqac-00000004, pqac-00000013) | (pqac-00000001, pqac-00000004, pqac-00000013) |
| 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. (pqac-00000004, pqac-00000005, pqac-00000007, pqac-00000011, pqac-00000012) | (pqac-00000004, pqac-00000005, pqac-00000007, pqac-00000011, pqac-00000012) |
| 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. (pqac-00000001, pqac-00000005, pqac-00000006, pqac-00000007, pqac-00000012, pqac-00000013) | (pqac-00000001, pqac-00000005, pqac-00000006, pqac-00000007, pqac-00000012, pqac-00000013) |
| 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. (pqac-00000004, pqac-00000007, pqac-00000011, pqac-00000012, pqac-00000014) | (pqac-00000004, pqac-00000007, pqac-00000011, pqac-00000012, pqac-00000014) |
| 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. (pqac-00000009) | (pqac-00000009) |
| 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. (pqac-00000004, pqac-00000008, pqac-00000011, pqac-00000012) | (pqac-00000004, pqac-00000008, pqac-00000011, pqac-00000012) |
| 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. (pqac-00000004, pqac-00000014) | (pqac-00000004, pqac-00000014) |
| 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. (pqac-00000004, pqac-00000010, pqac-00000011) | (pqac-00000004, pqac-00000010, pqac-00000011) |


*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.*