{"gene":"EIF4ENIF1","run_date":"2026-06-09T23:54:42","timeline":{"discoveries":[{"year":2000,"finding":"4E-T mediates nuclear import of eIF4E via the importin αβ pathway by a piggyback mechanism; 4E-T contains a bipartite nuclear localization signal and two leucine-rich nuclear export signals, and eIF4E forms a complex with the importin αβ heterodimer only in the presence of 4E-T.","method":"Co-immunoprecipitation, overexpression of wild-type and eIF4E-binding-deficient mutant 4E-T, leptomycin B treatment, nuclear accumulation assay","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP with mutagenesis, multiple orthogonal methods in a single rigorous study, replicated in subsequent work","pmids":["10856257"],"is_preprint":false},{"year":2005,"finding":"4E-T colocalizes with mRNA decapping factors in P-bodies and controls mRNA half-life; siRNA depletion of 4E-T increases mRNA stability, and 4E-T interaction with eIF4E represses translation, which is a prerequisite for targeting mRNAs to P-bodies.","method":"siRNA knockdown with mRNA stability assay, co-localization by fluorescence microscopy, co-immunoprecipitation","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — loss-of-function with defined mRNA stability phenotype, co-localization, Co-IP; independently replicated across multiple subsequent studies","pmids":["16157702"],"is_preprint":false},{"year":2005,"finding":"Murine Clast4 (4E-T ortholog) is expressed in growing oocytes and undergoes phosphorylation upon meiotic maturation; direct interaction with eIF4E is mediated by a canonical and functional eIF4E-binding motif.","method":"Western blot, co-immunoprecipitation, phosphorylation assay, in situ hybridization","journal":"Gene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct binding confirmed by Co-IP with functional motif, post-translational modification by phosphorylation demonstrated, single lab","pmids":["16343815"],"is_preprint":false},{"year":2007,"finding":"In early Xenopus oocytes, 4E-T interacts with CPEB, the RNA helicase Xp54, RNA-binding proteins P100(Pat1) and RAP55, and the oocyte-specific eIF4E1b (not canonical eIF4E1a); 4E-T binding to eIF4E1b occurs independently of the consensus YSKEELL eIF4E-binding motif and represses translation in a cap-dependent manner.","method":"Co-immunoprecipitation, gel filtration, pull-down assays, tether function assays in Xenopus oocytes, antibody injection","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP, pull-down, gel filtration, and functional tether assays with multiple mutants; multiple orthogonal methods","pmids":["17942399"],"is_preprint":false},{"year":2012,"finding":"JNK phosphorylates 4E-T on six proline-directed sites in response to oxidative stress, and this phosphorylation is required for formation of the 4E-T complex and facilitates assembly of larger P-bodies under stress; 4E-T phosphorylation does not impact global translational control.","method":"Quantitative mass spectrometry, kinase assay, image-based computational P-body quantification, polysomal mRNA profiling, siRNA knockdown","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — quantitative MS site identification, kinase assay, multiple functional readouts including polysome profiling; rigorous single-lab study with multiple orthogonal methods","pmids":["22966201"],"is_preprint":false},{"year":2013,"finding":"4E-T represses translation of bound mRNAs in a tether-function assay independently of its eIF4E-binding site (YX4L) and independently of P-body localization; global translational repression requires eIF4E binding; depletion of 4E-T from HeLa cells increases steady-state translation and relieves microRNA-mediated silencing.","method":"Tether function assay, siRNA knockdown with polysome analysis, mutagenesis of eIF4E-binding motif, qPCR, northern blot","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — reconstitution via tether assay with mutagenesis, loss-of-function with multiple readouts, multiple orthogonal methods","pmids":["24335285"],"is_preprint":false},{"year":2014,"finding":"In embryonic cortical neural precursors, 4E-T forms a repressive complex with eIF4E1 that sequesters and represses translation of proneurogenic bHLH mRNAs; disruption of this complex causes premature neurogenesis and neural precursor depletion.","method":"Co-immunoprecipitation, RNA-immunoprecipitation, knockdown by shRNA/siRNA with neurogenesis phenotype readout, co-localization with Lsm1 and Rck in granules","journal":"Neuron","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP, RNA-IP, loss-of-function with defined cellular and molecular phenotype, multiple orthogonal methods","pmids":["25456498"],"is_preprint":false},{"year":2015,"finding":"4E-T interacts with DDX6 via its CUP-homology domain (CHD), which wraps around the RecA2 domain of DDX6 and contacts CNOT1; the crystal structure (2.1 Å) reveals that 4E-T CHD shares the same DDX6-binding surface as Edc3 and Pat1 FDF motifs, but unlike Edc3/Pat1, 4E-T CHD maintains DDX6 binding even upon CNOT1 MIF4G domain binding.","method":"X-ray crystallography at 2.1 Å, in vitro binding assay, co-immunoprecipitation","journal":"Cell reports","confidence":"High","confidence_rationale":"Tier 1 / Strong — atomic-resolution crystal structure with functional validation by binding assays; rigorous single-study with structural and biochemical methods","pmids":["26489469"],"is_preprint":false},{"year":2015,"finding":"4E-T bridges the 5' cap (via eIF4E binding) and 3' mRNA decay machinery (via interactions with DDX6, LSM14, and LSM1-7-PAT1 complex) to promote mRNA decay; 4E-T must interact with eIF4E to engender mRNA decay of microRNA targets.","method":"Co-immunoprecipitation, mass spectrometry, tether function assay, mRNA decay assay, mutagenesis","journal":"Cell reports","confidence":"High","confidence_rationale":"Tier 2 / Strong — MS-identified interactome with Co-IP validation, functional mutagenesis of eIF4E-binding site, multiple orthogonal methods","pmids":["26027925"],"is_preprint":false},{"year":2015,"finding":"In Xenopus oocytes, 4E-T acts downstream of NOT1 in a CAF1–CCR4-NOT–Xp54–4E-T repression chain; a 4E-T truncation that still binds eIF4E alleviates repression by tethered CAF1, NOT1, and Xp54, while a mutant 4E-T failing to bind eIF4E does not, indicating eIF4E-dependent activity is required for this repression axis.","method":"Tether function assay in Xenopus oocytes, affinity purification-mass spectrometry, co-immunoprecipitation, 4E-T truncation/mutation analysis","journal":"RNA (New York, N.Y.)","confidence":"High","confidence_rationale":"Tier 2 / Strong — epistasis via tether assay with multiple defined mutants, AP-MS, Co-IP; multiple orthogonal methods","pmids":["26015597"],"is_preprint":false},{"year":2015,"finding":"Phosphomimetic eIF4E (S209D) requires direct interaction with 4E-T to confer resistance to oxidative stress and DNA-damaging agents; knockdown of 4E-T or use of an eIF4E-W73A-S209D mutant unable to bind 4E-T abolishes the stress resistance phenotype.","method":"Retroviral expression of phosphomimetic/phospho-dead eIF4E mutants, 4E-T siRNA knockdown, eIF4E-W73A mutagenesis, cell viability assay, polysome analysis","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional mutagenesis and knockdown with defined phenotype, single lab, two orthogonal approaches","pmids":["25923732"],"is_preprint":false},{"year":2016,"finding":"4E-T interacts with DDX6, UNR, unrip, PAT1B, LSM14A, and CNOT4 via distinct sites identified by mass spectrometry; joint deletion of two short conserved motifs binding UNR and DDX6 relieves translational repression; the DDX6–4E-T interaction mediates both miRNA-dependent translational repression and de novo P-body assembly.","method":"Mass spectrometry, western blotting, tether function assay, deletion mutagenesis, miRNA reporter assay, P-body assembly assay","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 2 / Strong — MS-identified interactome with mutagenesis-validated binding sites, multiple functional readouts, multiple orthogonal methods in single rigorous study","pmids":["27342281"],"is_preprint":false},{"year":2020,"finding":"4E-T promotes deadenylation of bound mRNAs via recruitment of the CCR4-NOT complex through previously uncharacterized sites in its middle region, while simultaneously inhibiting mRNA decapping and degradation through its interaction with cap-binding proteins eIF4E/4EHP, thereby storing mRNAs in a deadenylated, repressed form.","method":"Tether function assay, mutagenesis of CCR4-NOT interaction sites, mRNA decay assay, co-immunoprecipitation, 4E-T overexpression","journal":"Genes & development","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — reconstitution by tether assay with defined mutagenesis of multiple interaction sites, mRNA stability assays, multiple orthogonal methods in single study","pmids":["32354837"],"is_preprint":false},{"year":2022,"finding":"The deubiquitinase OTUD4 and E3 ubiquitin ligase TRIM56 counter-regulate the ubiquitination status of 4E-T to control P-body assembly in neural progenitor cells; aberrant 4E-T ubiquitination promotes P-body assembly and delays cell cycle progression, while loss of 4E-T ubiquitination abrogates P-bodies and causes premature neurogenesis.","method":"Deubiquitinase/E3-ligase identification, ubiquitination assay, genetic manipulation of OTUD4 and TRIM56, P-body quantification, neural progenitor differentiation assay","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — writer/eraser identified with functional P-body and differentiation phenotypes, single lab with defined cellular readouts","pmids":["35830814"],"is_preprint":false},{"year":2023,"finding":"An intramolecular disulphide bond between two cysteines located between the 4E-binding motifs of human 4E-T reduces its affinity for eIF4E1a by approximately 300-fold, functioning as a redox-sensitive switch regulating the 4E-T–eIF4E interaction.","method":"Biophysical binding assay under non-reducing conditions, mutagenesis, affinity measurement","journal":"European biophysics journal : EBJ","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — in vitro biochemical reconstitution with quantitative affinity measurement, single lab, single study","pmids":["37798395"],"is_preprint":false},{"year":2023,"finding":"In early postnatal forebrain NPCs, 4E-T broadly associates with mRNAs encoding transcriptional regulators that are depleted from ribosomes; 4E-T knockdown or conditional knockout derepresses proneurogenic mRNA translation and perturbs NPC maintenance vs. differentiation in vivo.","method":"RNA-immunoprecipitation, ribosome profiling, conditional knockout, shRNA knockdown, in vivo neurogenesis phenotype assay","journal":"Cell reports","confidence":"High","confidence_rationale":"Tier 2 / Strong — conditional KO with defined in vivo phenotype, RNA-IP, ribosome profiling; multiple orthogonal methods","pmids":["36924490"],"is_preprint":false},{"year":2024,"finding":"Overexpression of EIF4ENIF1 wild-type significantly reduces global translation efficiency; a POI-associated mutant Q842P fails to repress global translation, while R208H has a reduced inhibitory effect on high-TE genes; several fertility-associated genes (AMH, SERPINE1, THBS1) are translationally upregulated in mutant groups versus wild-type.","method":"T&T-seq (translation-transcription dual-omics sequencing), overexpression of WT and mutant EIF4ENIF1 in 293FT cells","journal":"Gene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genome-wide translational profiling with defined mutant comparisons, single lab, single method platform","pmids":["38604507"],"is_preprint":false},{"year":2025,"finding":"4E-T is required to maintain prophase-I arrest in mouse and frog oocytes; acute loss of 4E-T (via TRIM-Away) causes spontaneous meiotic resumption due to untimely translation of c-Mos and cyclin-B1; 4E-T association with eIF4E and PATL2 is critical for target mRNA binding and repression; a POI-associated 4E-T mutant fails to maintain prophase-I arrest in Xenopus oocytes.","method":"TRIM-Away acute protein depletion, western blot for c-Mos and cyclin-B1, meiotic maturation assay in mouse and Xenopus oocytes, co-immunoprecipitation of 4E-T with eIF4E and PATL2, mutagenesis","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — fast-acting acute loss-of-function with defined molecular phenotype (meiotic driver derepression), multiple orthogonal methods, two species (mouse and frog), functional mutagenesis","pmids":["40877279"],"is_preprint":false}],"current_model":"EIF4ENIF1 (4E-T) is a nucleocytoplasmic shuttling protein that mediates nuclear import of eIF4E via the importin αβ pathway, localizes to P-bodies where it represses translation and modulates mRNA fate by simultaneously recruiting the CCR4-NOT deadenylase complex (through its middle region), binding eIF4E/4EHP at the 5' cap, and interacting with DDX6 (via its CUP-homology domain), LSM14A, PAT1B, UNR, and CNOT4 to form a multi-protein repressive network; it promotes deadenylation while inhibiting decapping to store mRNAs in a silenced form rather than committing them to degradation, can repress translation both in an eIF4E-dependent (global) and eIF4E-independent (tethered mRNA) manner, undergoes stress-induced phosphorylation by JNK on six proline-directed sites to drive P-body enlargement, and is regulated by ubiquitination (written by TRIM56, erased by OTUD4) and by an intramolecular disulphide bond that reduces eIF4E affinity ~300-fold; in neural progenitors it sequesters proneurogenic mRNAs to balance self-renewal and differentiation, and in oocytes it is essential for maintaining prophase-I arrest by repressing key meiotic drivers such as c-Mos and cyclin-B1."},"narrative":{"mechanistic_narrative":"EIF4ENIF1 (4E-T) is a translational repressor and mRNA-fate regulator that bridges 5' cap recognition to the 3' decay and storage machinery, partitioning bound transcripts into a silenced rather than degraded state [PMID:26027925, PMID:32354837]. It was first defined as a nucleocytoplasmic shuttling protein that mediates piggyback nuclear import of eIF4E via the importin αβ pathway, carrying a bipartite nuclear localization signal and leucine-rich export signals [PMID:10856257]. In the cytoplasm 4E-T concentrates in P-bodies, where its eIF4E interaction represses translation and controls mRNA half-life [PMID:16157702]. Mechanistically, 4E-T scaffolds a repressive ribonucleoprotein network: it binds the 5' cap through eIF4E (and the related 4EHP), engages the DEAD-box helicase DDX6 through its CUP-homology domain in a manner that uniquely tolerates simultaneous CNOT1 binding, and contacts LSM14A, the LSM1-7–PAT1B complex, UNR, and CNOT4 [PMID:26489469, PMID:26027925, PMID:27342281]. Through sites in its middle region it recruits the CCR4-NOT deadenylase to promote deadenylation while its cap-binding interactions inhibit decapping and degradation, thereby storing transcripts in a deadenylated, repressed form [PMID:32354837]. 4E-T can silence tethered mRNAs independently of its eIF4E-binding motif and independently of P-body localization, whereas global translational repression and miRNA-mediated decay require eIF4E binding [PMID:24335285, PMID:26027925]. Its activity is tuned post-translationally: JNK phosphorylates six proline-directed sites under oxidative stress to drive P-body enlargement and complex assembly [PMID:22966201], TRIM56 and OTUD4 write and erase ubiquitin to control P-body formation [PMID:35830814], and a redox-sensitive intramolecular disulphide bond lowers eIF4E affinity ~300-fold [PMID:37798395]. Biologically, 4E-T sequesters proneurogenic bHLH and transcription-regulator mRNAs in neural precursors to balance self-renewal against differentiation, with its loss causing premature neurogenesis [PMID:25456498, PMID:36924490], and it maintains oocyte prophase-I arrest by repressing meiotic drivers c-Mos and cyclin-B1 [PMID:40877279].","teleology":[{"year":2000,"claim":"Established the founding molecular role of 4E-T: how the cap-binding protein eIF4E reaches the nucleus, by showing 4E-T is an eIF4E-dependent nuclear import adaptor.","evidence":"Co-IP, eIF4E-binding-deficient mutants, leptomycin B and nuclear accumulation assays","pmids":["10856257"],"confidence":"High","gaps":["Did not address cytoplasmic translational functions","Functional consequence of eIF4E nuclear import on gene expression not defined"]},{"year":2005,"claim":"Reframed 4E-T as a cytoplasmic mRNA-fate regulator by placing it in P-bodies and linking its eIF4E interaction to translational repression and mRNA stability control.","evidence":"siRNA knockdown with mRNA stability assay, fluorescence co-localization, Co-IP","pmids":["16157702"],"confidence":"High","gaps":["Did not resolve whether 4E-T promotes or protects against decay","Repressive partners beyond eIF4E not yet identified"]},{"year":2007,"claim":"Showed the repressive complex is context-specific, identifying an oocyte 4E-T network with CPEB, Xp54, Pat1, RAP55 and the oocyte-specific eIF4E1b, with cap-dependent repression not requiring the canonical eIF4E-binding motif.","evidence":"Co-IP, gel filtration, pull-downs and tether assays in Xenopus oocytes","pmids":["17942399"],"confidence":"High","gaps":["Mechanism of motif-independent eIF4E1b binding undefined","Direct vs. indirect nature of several interactions not resolved"]},{"year":2012,"claim":"Identified stress-responsive regulation of 4E-T, defining JNK phosphorylation of six proline-directed sites as a switch for complex assembly and P-body enlargement.","evidence":"Quantitative MS, kinase assay, image-based P-body quantification, polysome profiling, siRNA","pmids":["22966201"],"confidence":"High","gaps":["Which target mRNAs are affected by phosphorylation not mapped","Phosphorylation shown not to alter global translation, leaving the functional output narrow"]},{"year":2013,"claim":"Dissected the two modes of repression, showing tethered-mRNA silencing is eIF4E-independent and P-body-independent while global repression and miRNA silencing relief require eIF4E binding.","evidence":"Tether assay, polysome analysis, eIF4E-binding-motif mutagenesis, qPCR, northern blot","pmids":["24335285"],"confidence":"High","gaps":["Effector mediating eIF4E-independent repression not identified","Endogenous target set not defined"]},{"year":2014,"claim":"Assigned an in vivo developmental function, showing a 4E-T–eIF4E1 complex sequesters proneurogenic bHLH mRNAs to maintain neural precursors.","evidence":"Co-IP, RNA-IP, shRNA/siRNA with neurogenesis phenotype, granule co-localization","pmids":["25456498"],"confidence":"High","gaps":["Mechanism of mRNA selectivity unclear","Reversibility/derepression trigger during normal differentiation not defined"]},{"year":2015,"claim":"Resolved at atomic resolution how 4E-T engages the decay machinery, showing its CUP-homology domain wraps DDX6 and contacts CNOT1, uniquely retaining DDX6 binding when CNOT1 is engaged.","evidence":"2.1 Å X-ray crystallography, in vitro binding, Co-IP","pmids":["26489469"],"confidence":"High","gaps":["Functional consequence of simultaneous DDX6/CNOT1 engagement on individual mRNAs not measured","Structure of full repressive assembly unresolved"]},{"year":2015,"claim":"Defined 4E-T as a cap-to-decay bridge, mapping interactions with eIF4E, DDX6, LSM14 and LSM1-7–PAT1 and showing eIF4E binding is required for decay of miRNA targets.","evidence":"Co-IP, MS interactome, tether and mRNA decay assays, mutagenesis","pmids":["26027925"],"confidence":"High","gaps":["Why some 4E-T activities favor decay while others favor storage not reconciled here"]},{"year":2015,"claim":"Placed 4E-T epistatically downstream of CCR4-NOT, establishing a CAF1–CCR4-NOT–Xp54–4E-T repression chain dependent on eIF4E binding.","evidence":"Tether/epistasis assays in Xenopus oocytes, AP-MS, Co-IP, truncation/mutation analysis","pmids":["26015597"],"confidence":"High","gaps":["Generality of the chain order outside oocytes not tested"]},{"year":2015,"claim":"Linked 4E-T to stress survival, showing phosphomimetic eIF4E requires 4E-T binding to confer resistance to oxidative and DNA-damaging stress.","evidence":"Phosphomimetic/phospho-dead eIF4E expression, 4E-T knockdown, eIF4E-W73A mutagenesis, viability and polysome assays","pmids":["25923732"],"confidence":"Medium","gaps":["Single lab; downstream survival effectors not identified","Mechanistic link between 4E-T binding and stress resistance unresolved"]},{"year":2016,"claim":"Comprehensively mapped the 4E-T interactome to distinct motifs, showing UNR and DDX6 binding sites cooperatively mediate repression and DDX6 binding drives de novo P-body assembly.","evidence":"MS, western blot, tether assay, deletion mutagenesis, miRNA reporter and P-body assays","pmids":["27342281"],"confidence":"High","gaps":["Stoichiometry and order of assembly of the multi-partner complex not defined"]},{"year":2020,"claim":"Reconciled the storage-versus-decay paradox, showing 4E-T promotes deadenylation via middle-region CCR4-NOT recruitment while cap-binding interactions inhibit decapping, storing mRNAs in a deadenylated repressed state.","evidence":"Tether assay, CCR4-NOT site mutagenesis, mRNA decay assay, Co-IP, overexpression","pmids":["32354837"],"confidence":"High","gaps":["Signals that convert stored mRNAs to degradation or reactivation not defined","In vivo relevance of the storage state across tissues untested here"]},{"year":2022,"claim":"Identified ubiquitin as a regulatory layer, with TRIM56 (writer) and OTUD4 (eraser) tuning 4E-T ubiquitination to control P-body assembly and neural progenitor cell-cycle progression.","evidence":"DUB/E3 identification, ubiquitination assays, OTUD4/TRIM56 manipulation, P-body and differentiation assays","pmids":["35830814"],"confidence":"Medium","gaps":["Ubiquitinated residues and chain type not defined","Single lab; link between ubiquitination and specific mRNA fate not established"]},{"year":2023,"claim":"Defined a redox switch on 4E-T, showing an intramolecular disulphide between the 4E-binding motifs reduces eIF4E affinity ~300-fold.","evidence":"Biophysical binding under non-reducing conditions, mutagenesis, affinity measurement","pmids":["37798395"],"confidence":"Medium","gaps":["In vitro only; cellular evidence that the disulphide forms under physiological oxidation lacking","Functional consequence for mRNA fate not tested"]},{"year":2023,"claim":"Extended the neural role transcriptome-wide and in vivo, showing 4E-T associates with ribosome-depleted transcription-regulator mRNAs and is required for NPC maintenance versus differentiation.","evidence":"RNA-IP, ribosome profiling, conditional KO and shRNA, in vivo neurogenesis phenotype","pmids":["36924490"],"confidence":"High","gaps":["Selectivity determinants for bound mRNAs not defined","Coupling to specific decay/storage outcomes per transcript unresolved"]},{"year":2024,"claim":"Connected 4E-T to human fertility disease, showing wild-type represses global translation while POI-associated mutants (Q842P, R208H) fail to repress and derepress fertility-associated transcripts.","evidence":"T&T-seq dual-omics with WT and mutant overexpression in 293FT cells","pmids":["38604507"],"confidence":"Medium","gaps":["Heterologous 293FT system, not oocytes","Causal link between specific derepressed transcripts and disease phenotype not established"]},{"year":2025,"claim":"Established 4E-T as essential for oocyte prophase-I arrest, showing acute loss triggers meiotic resumption via untimely c-Mos and cyclin-B1 translation, dependent on eIF4E and PATL2 binding.","evidence":"TRIM-Away acute depletion, western blot, meiotic maturation assays in mouse and Xenopus, Co-IP, mutagenesis","pmids":["40877279"],"confidence":"High","gaps":["Full set of arrest-maintaining target mRNAs not defined","How fertilization/maturation signals relieve 4E-T repression unresolved"]},{"year":null,"claim":"How the multiple regulatory inputs (JNK phosphorylation, TRIM56/OTUD4 ubiquitination, redox disulphide) are integrated to choose between mRNA storage, decay, and reactivation in a tissue-specific manner remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unified model linking the regulatory modifications to specific mRNA-fate outcomes","Determinants of 4E-T target mRNA selectivity unknown","Reactivation/derepression triggers across cell types undefined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0045182","term_label":"translation regulator activity","supporting_discovery_ids":[1,5,8,12,16,17]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[0,7,8,11]},{"term_id":"GO:0140313","term_label":"molecular sequestering activity","supporting_discovery_ids":[12,6,15]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[12,9]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[1,4,11]}],"pathway":[{"term_id":"R-HSA-8953854","term_label":"Metabolism of RNA","supporting_discovery_ids":[1,8,12]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[6,15]},{"term_id":"R-HSA-1474165","term_label":"Reproduction","supporting_discovery_ids":[17]}],"complexes":["P-body","CCR4-NOT (recruited)","4E-T–eIF4E repressive complex","LSM1-7–PAT1 complex (associated)"],"partners":["EIF4E","DDX6","LSM14A","PATL2","CNOT1","UNR","CNOT4","EIF4E1B"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9NRA8","full_name":"Eukaryotic translation initiation factor 4E transporter","aliases":["Eukaryotic translation initiation factor 4E nuclear import factor 1"],"length_aa":985,"mass_kda":108.2,"function":"EIF4E-binding protein that regulates translation and stability of mRNAs in processing bodies (P-bodies) (PubMed:16157702, PubMed:24335285, PubMed:27342281, PubMed:32354837). Plays a key role in P-bodies to coordinate the storage of translationally inactive mRNAs in the cytoplasm and prevent their degradation (PubMed:24335285, PubMed:32354837). Acts as a binding platform for multiple RNA-binding proteins: promotes deadenylation of mRNAs via its interaction with the CCR4-NOT complex, and blocks decapping via interaction with eIF4E (EIF4E and EIF4E2), thereby protecting deadenylated and repressed mRNAs from degradation (PubMed:27342281, PubMed:32354837). Component of a multiprotein complex that sequesters and represses translation of proneurogenic factors during neurogenesis (By similarity). Promotes miRNA-mediated translational repression (PubMed:24335285, PubMed:27342281, PubMed:28487484). Required for the formation of P-bodies (PubMed:16157702, PubMed:22966201, PubMed:27342281, PubMed:32354837). Involved in mRNA translational repression mediated by the miRNA effector TNRC6B by protecting TNRC6B-targeted mRNAs from decapping and subsequent decay (PubMed:32354837). Also acts as a nucleoplasmic shuttling protein, which mediates the nuclear import of EIF4E and DDX6 by a piggy-back mechanism (PubMed:10856257, PubMed:28216671)","subcellular_location":"Cytoplasm, P-body; Cytoplasm; Nucleus; Nucleus, PML body; Nucleus speckle","url":"https://www.uniprot.org/uniprotkb/Q9NRA8/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/EIF4ENIF1","classification":"Not Classified","n_dependent_lines":56,"n_total_lines":1208,"dependency_fraction":0.046357615894039736},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"CAPZB","stoichiometry":0.2},{"gene":"DDX6","stoichiometry":0.2},{"gene":"LSM14A","stoichiometry":0.2},{"gene":"LSM14B","stoichiometry":0.2},{"gene":"SNRPC","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/EIF4ENIF1","total_profiled":1310},"omim":[{"mim_id":"614660","title":"PAT1 HOMOLOG 1, PROCESSING BODY mRNA DECAY FACTOR; PATL1","url":"https://www.omim.org/entry/614660"},{"mim_id":"607445","title":"EUKARYOTIC TRANSLATION INITIATION FACTOR 4E NUCLEAR IMPORT FACTOR 1; EIF4ENIF1","url":"https://www.omim.org/entry/607445"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Vesicles","reliability":"Approved"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/EIF4ENIF1"},"hgnc":{"alias_symbol":["4E-T","FLJ21601","Clast4","2610509L04Rik"],"prev_symbol":[]},"alphafold":{"accession":"Q9NRA8","domains":[],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9NRA8","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9NRA8-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9NRA8-F1-predicted_aligned_error_v6.png","plddt_mean":50.59},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=EIF4ENIF1","jax_strain_url":"https://www.jax.org/strain/search?query=EIF4ENIF1"},"sequence":{"accession":"Q9NRA8","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9NRA8.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9NRA8/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9NRA8"}},"corpus_meta":[{"pmid":"16157702","id":"PMC_16157702","title":"A role for the eIF4E-binding protein 4E-T in P-body formation and mRNA decay.","date":"2005","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/16157702","citation_count":204,"is_preprint":false},{"pmid":"10856257","id":"PMC_10856257","title":"A novel shuttling protein, 4E-T, mediates the nuclear import of the mRNA 5' cap-binding protein, eIF4E.","date":"2000","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/10856257","citation_count":165,"is_preprint":false},{"pmid":"17942399","id":"PMC_17942399","title":"CPEB interacts with an ovary-specific eIF4E and 4E-T in early Xenopus oocytes.","date":"2007","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/17942399","citation_count":151,"is_preprint":false},{"pmid":"27342281","id":"PMC_27342281","title":"The DDX6-4E-T interaction mediates translational repression and P-body assembly.","date":"2016","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/27342281","citation_count":104,"is_preprint":false},{"pmid":"26489469","id":"PMC_26489469","title":"Structure of a Human 4E-T/DDX6/CNOT1 Complex Reveals the Different Interplay of DDX6-Binding Proteins with the CCR4-NOT Complex.","date":"2015","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/26489469","citation_count":90,"is_preprint":false},{"pmid":"25456498","id":"PMC_25456498","title":"An eIF4E1/4E-T complex determines the genesis of neurons from precursors by translationally repressing a proneurogenic transcription program.","date":"2014","source":"Neuron","url":"https://pubmed.ncbi.nlm.nih.gov/25456498","citation_count":80,"is_preprint":false},{"pmid":"24335285","id":"PMC_24335285","title":"Human 4E-T represses translation of bound mRNAs and enhances microRNA-mediated silencing.","date":"2013","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/24335285","citation_count":70,"is_preprint":false},{"pmid":"26027925","id":"PMC_26027925","title":"The eIF4E-Binding Protein 4E-T Is a Component of the mRNA Decay Machinery that Bridges the 5' and 3' Termini of Target mRNAs.","date":"2015","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/26027925","citation_count":69,"is_preprint":false},{"pmid":"23902945","id":"PMC_23902945","title":"Mutations in eIF4ENIF1 are associated with primary ovarian insufficiency.","date":"2013","source":"The Journal of clinical endocrinology and metabolism","url":"https://pubmed.ncbi.nlm.nih.gov/23902945","citation_count":53,"is_preprint":false},{"pmid":"32354837","id":"PMC_32354837","title":"4E-T-bound mRNAs are stored in a silenced and deadenylated form.","date":"2020","source":"Genes & development","url":"https://pubmed.ncbi.nlm.nih.gov/32354837","citation_count":41,"is_preprint":false},{"pmid":"25923732","id":"PMC_25923732","title":"Phosphorylation of eIF4E Confers Resistance to Cellular Stress and DNA-Damaging Agents through an Interaction with 4E-T: A Rationale for Novel Therapeutic Approaches.","date":"2015","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/25923732","citation_count":38,"is_preprint":false},{"pmid":"31810472","id":"PMC_31810472","title":"A novel EIF4ENIF1 mutation associated with a diminished ovarian reserve and premature ovarian insufficiency identified by whole-exome sequencing.","date":"2019","source":"Journal of ovarian research","url":"https://pubmed.ncbi.nlm.nih.gov/31810472","citation_count":35,"is_preprint":false},{"pmid":"22966201","id":"PMC_22966201","title":"Phosphorylation of the eukaryotic translation initiation factor 4E-transporter (4E-T) by c-Jun N-terminal kinase promotes stress-dependent P-body assembly.","date":"2012","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/22966201","citation_count":30,"is_preprint":false},{"pmid":"16343815","id":"PMC_16343815","title":"Clast4, the murine homologue of human eIF4E-Transporter, is highly expressed in developing oocytes and post-translationally modified at meiotic maturation.","date":"2005","source":"Gene","url":"https://pubmed.ncbi.nlm.nih.gov/16343815","citation_count":27,"is_preprint":false},{"pmid":"26015597","id":"PMC_26015597","title":"Xenopus CAF1 requires NOT1-mediated interaction with 4E-T to repress translation in vivo.","date":"2015","source":"RNA (New York, N.Y.)","url":"https://pubmed.ncbi.nlm.nih.gov/26015597","citation_count":25,"is_preprint":false},{"pmid":"35830814","id":"PMC_35830814","title":"Ubiquitination and deubiquitination of 4E-T regulate neural progenitor cell maintenance and neurogenesis by controlling P-body formation.","date":"2022","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/35830814","citation_count":11,"is_preprint":false},{"pmid":"36030004","id":"PMC_36030004","title":"EIF4ENIF1 variants in two patients with non-syndromic premature ovarian insufficiency.","date":"2022","source":"European journal of medical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/36030004","citation_count":10,"is_preprint":false},{"pmid":"36924490","id":"PMC_36924490","title":"The P-body protein 4E-T represses translation to regulate the balance between cell genesis and establishment of the postnatal NSC pool.","date":"2023","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/36924490","citation_count":6,"is_preprint":false},{"pmid":"34377067","id":"PMC_34377067","title":"Loss-of-function of Nicotiana tabacum L. eukaryotic translation initiation factors eIF4E1-S and eIF(iso)4E-T synergistically confers high-level resistance to both Potato virus Y (PVY) and resistance-breaking PVY.","date":"2021","source":"Breeding science","url":"https://pubmed.ncbi.nlm.nih.gov/34377067","citation_count":5,"is_preprint":false},{"pmid":"38604507","id":"PMC_38604507","title":"POI-associated EIF4ENIF1 mutations exhibit impaired translation regulation abilities.","date":"2024","source":"Gene","url":"https://pubmed.ncbi.nlm.nih.gov/38604507","citation_count":4,"is_preprint":false},{"pmid":"40877279","id":"PMC_40877279","title":"Translational repression by 4E-T is crucial to maintain the prophase-I arrest in vertebrate oocytes.","date":"2025","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/40877279","citation_count":2,"is_preprint":false},{"pmid":"37798395","id":"PMC_37798395","title":"An intramolecular disulphide bond in human 4E-T affects its binding to eIF4E1a protein.","date":"2023","source":"European biophysics journal : EBJ","url":"https://pubmed.ncbi.nlm.nih.gov/37798395","citation_count":1,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":12282,"output_tokens":4722,"usd":0.053838,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":12739,"output_tokens":5381,"usd":0.09911,"stage2_stop_reason":"end_turn"},"total_usd":0.152948,"stage1_batch_id":"msgbatch_01AsR7g8dGTEiEw9U83bJeWn","stage2_batch_id":"msgbatch_01YV5ZyxtFNUZEjxRcpd9jzb","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2000,\n      \"finding\": \"4E-T mediates nuclear import of eIF4E via the importin αβ pathway by a piggyback mechanism; 4E-T contains a bipartite nuclear localization signal and two leucine-rich nuclear export signals, and eIF4E forms a complex with the importin αβ heterodimer only in the presence of 4E-T.\",\n      \"method\": \"Co-immunoprecipitation, overexpression of wild-type and eIF4E-binding-deficient mutant 4E-T, leptomycin B treatment, nuclear accumulation assay\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP with mutagenesis, multiple orthogonal methods in a single rigorous study, replicated in subsequent work\",\n      \"pmids\": [\"10856257\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"4E-T colocalizes with mRNA decapping factors in P-bodies and controls mRNA half-life; siRNA depletion of 4E-T increases mRNA stability, and 4E-T interaction with eIF4E represses translation, which is a prerequisite for targeting mRNAs to P-bodies.\",\n      \"method\": \"siRNA knockdown with mRNA stability assay, co-localization by fluorescence microscopy, co-immunoprecipitation\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — loss-of-function with defined mRNA stability phenotype, co-localization, Co-IP; independently replicated across multiple subsequent studies\",\n      \"pmids\": [\"16157702\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Murine Clast4 (4E-T ortholog) is expressed in growing oocytes and undergoes phosphorylation upon meiotic maturation; direct interaction with eIF4E is mediated by a canonical and functional eIF4E-binding motif.\",\n      \"method\": \"Western blot, co-immunoprecipitation, phosphorylation assay, in situ hybridization\",\n      \"journal\": \"Gene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct binding confirmed by Co-IP with functional motif, post-translational modification by phosphorylation demonstrated, single lab\",\n      \"pmids\": [\"16343815\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"In early Xenopus oocytes, 4E-T interacts with CPEB, the RNA helicase Xp54, RNA-binding proteins P100(Pat1) and RAP55, and the oocyte-specific eIF4E1b (not canonical eIF4E1a); 4E-T binding to eIF4E1b occurs independently of the consensus YSKEELL eIF4E-binding motif and represses translation in a cap-dependent manner.\",\n      \"method\": \"Co-immunoprecipitation, gel filtration, pull-down assays, tether function assays in Xenopus oocytes, antibody injection\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP, pull-down, gel filtration, and functional tether assays with multiple mutants; multiple orthogonal methods\",\n      \"pmids\": [\"17942399\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"JNK phosphorylates 4E-T on six proline-directed sites in response to oxidative stress, and this phosphorylation is required for formation of the 4E-T complex and facilitates assembly of larger P-bodies under stress; 4E-T phosphorylation does not impact global translational control.\",\n      \"method\": \"Quantitative mass spectrometry, kinase assay, image-based computational P-body quantification, polysomal mRNA profiling, siRNA knockdown\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — quantitative MS site identification, kinase assay, multiple functional readouts including polysome profiling; rigorous single-lab study with multiple orthogonal methods\",\n      \"pmids\": [\"22966201\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"4E-T represses translation of bound mRNAs in a tether-function assay independently of its eIF4E-binding site (YX4L) and independently of P-body localization; global translational repression requires eIF4E binding; depletion of 4E-T from HeLa cells increases steady-state translation and relieves microRNA-mediated silencing.\",\n      \"method\": \"Tether function assay, siRNA knockdown with polysome analysis, mutagenesis of eIF4E-binding motif, qPCR, northern blot\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — reconstitution via tether assay with mutagenesis, loss-of-function with multiple readouts, multiple orthogonal methods\",\n      \"pmids\": [\"24335285\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"In embryonic cortical neural precursors, 4E-T forms a repressive complex with eIF4E1 that sequesters and represses translation of proneurogenic bHLH mRNAs; disruption of this complex causes premature neurogenesis and neural precursor depletion.\",\n      \"method\": \"Co-immunoprecipitation, RNA-immunoprecipitation, knockdown by shRNA/siRNA with neurogenesis phenotype readout, co-localization with Lsm1 and Rck in granules\",\n      \"journal\": \"Neuron\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP, RNA-IP, loss-of-function with defined cellular and molecular phenotype, multiple orthogonal methods\",\n      \"pmids\": [\"25456498\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"4E-T interacts with DDX6 via its CUP-homology domain (CHD), which wraps around the RecA2 domain of DDX6 and contacts CNOT1; the crystal structure (2.1 Å) reveals that 4E-T CHD shares the same DDX6-binding surface as Edc3 and Pat1 FDF motifs, but unlike Edc3/Pat1, 4E-T CHD maintains DDX6 binding even upon CNOT1 MIF4G domain binding.\",\n      \"method\": \"X-ray crystallography at 2.1 Å, in vitro binding assay, co-immunoprecipitation\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — atomic-resolution crystal structure with functional validation by binding assays; rigorous single-study with structural and biochemical methods\",\n      \"pmids\": [\"26489469\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"4E-T bridges the 5' cap (via eIF4E binding) and 3' mRNA decay machinery (via interactions with DDX6, LSM14, and LSM1-7-PAT1 complex) to promote mRNA decay; 4E-T must interact with eIF4E to engender mRNA decay of microRNA targets.\",\n      \"method\": \"Co-immunoprecipitation, mass spectrometry, tether function assay, mRNA decay assay, mutagenesis\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — MS-identified interactome with Co-IP validation, functional mutagenesis of eIF4E-binding site, multiple orthogonal methods\",\n      \"pmids\": [\"26027925\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"In Xenopus oocytes, 4E-T acts downstream of NOT1 in a CAF1–CCR4-NOT–Xp54–4E-T repression chain; a 4E-T truncation that still binds eIF4E alleviates repression by tethered CAF1, NOT1, and Xp54, while a mutant 4E-T failing to bind eIF4E does not, indicating eIF4E-dependent activity is required for this repression axis.\",\n      \"method\": \"Tether function assay in Xenopus oocytes, affinity purification-mass spectrometry, co-immunoprecipitation, 4E-T truncation/mutation analysis\",\n      \"journal\": \"RNA (New York, N.Y.)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — epistasis via tether assay with multiple defined mutants, AP-MS, Co-IP; multiple orthogonal methods\",\n      \"pmids\": [\"26015597\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"Phosphomimetic eIF4E (S209D) requires direct interaction with 4E-T to confer resistance to oxidative stress and DNA-damaging agents; knockdown of 4E-T or use of an eIF4E-W73A-S209D mutant unable to bind 4E-T abolishes the stress resistance phenotype.\",\n      \"method\": \"Retroviral expression of phosphomimetic/phospho-dead eIF4E mutants, 4E-T siRNA knockdown, eIF4E-W73A mutagenesis, cell viability assay, polysome analysis\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional mutagenesis and knockdown with defined phenotype, single lab, two orthogonal approaches\",\n      \"pmids\": [\"25923732\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"4E-T interacts with DDX6, UNR, unrip, PAT1B, LSM14A, and CNOT4 via distinct sites identified by mass spectrometry; joint deletion of two short conserved motifs binding UNR and DDX6 relieves translational repression; the DDX6–4E-T interaction mediates both miRNA-dependent translational repression and de novo P-body assembly.\",\n      \"method\": \"Mass spectrometry, western blotting, tether function assay, deletion mutagenesis, miRNA reporter assay, P-body assembly assay\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — MS-identified interactome with mutagenesis-validated binding sites, multiple functional readouts, multiple orthogonal methods in single rigorous study\",\n      \"pmids\": [\"27342281\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"4E-T promotes deadenylation of bound mRNAs via recruitment of the CCR4-NOT complex through previously uncharacterized sites in its middle region, while simultaneously inhibiting mRNA decapping and degradation through its interaction with cap-binding proteins eIF4E/4EHP, thereby storing mRNAs in a deadenylated, repressed form.\",\n      \"method\": \"Tether function assay, mutagenesis of CCR4-NOT interaction sites, mRNA decay assay, co-immunoprecipitation, 4E-T overexpression\",\n      \"journal\": \"Genes & development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — reconstitution by tether assay with defined mutagenesis of multiple interaction sites, mRNA stability assays, multiple orthogonal methods in single study\",\n      \"pmids\": [\"32354837\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"The deubiquitinase OTUD4 and E3 ubiquitin ligase TRIM56 counter-regulate the ubiquitination status of 4E-T to control P-body assembly in neural progenitor cells; aberrant 4E-T ubiquitination promotes P-body assembly and delays cell cycle progression, while loss of 4E-T ubiquitination abrogates P-bodies and causes premature neurogenesis.\",\n      \"method\": \"Deubiquitinase/E3-ligase identification, ubiquitination assay, genetic manipulation of OTUD4 and TRIM56, P-body quantification, neural progenitor differentiation assay\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — writer/eraser identified with functional P-body and differentiation phenotypes, single lab with defined cellular readouts\",\n      \"pmids\": [\"35830814\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"An intramolecular disulphide bond between two cysteines located between the 4E-binding motifs of human 4E-T reduces its affinity for eIF4E1a by approximately 300-fold, functioning as a redox-sensitive switch regulating the 4E-T–eIF4E interaction.\",\n      \"method\": \"Biophysical binding assay under non-reducing conditions, mutagenesis, affinity measurement\",\n      \"journal\": \"European biophysics journal : EBJ\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — in vitro biochemical reconstitution with quantitative affinity measurement, single lab, single study\",\n      \"pmids\": [\"37798395\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"In early postnatal forebrain NPCs, 4E-T broadly associates with mRNAs encoding transcriptional regulators that are depleted from ribosomes; 4E-T knockdown or conditional knockout derepresses proneurogenic mRNA translation and perturbs NPC maintenance vs. differentiation in vivo.\",\n      \"method\": \"RNA-immunoprecipitation, ribosome profiling, conditional knockout, shRNA knockdown, in vivo neurogenesis phenotype assay\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — conditional KO with defined in vivo phenotype, RNA-IP, ribosome profiling; multiple orthogonal methods\",\n      \"pmids\": [\"36924490\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Overexpression of EIF4ENIF1 wild-type significantly reduces global translation efficiency; a POI-associated mutant Q842P fails to repress global translation, while R208H has a reduced inhibitory effect on high-TE genes; several fertility-associated genes (AMH, SERPINE1, THBS1) are translationally upregulated in mutant groups versus wild-type.\",\n      \"method\": \"T&T-seq (translation-transcription dual-omics sequencing), overexpression of WT and mutant EIF4ENIF1 in 293FT cells\",\n      \"journal\": \"Gene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genome-wide translational profiling with defined mutant comparisons, single lab, single method platform\",\n      \"pmids\": [\"38604507\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"4E-T is required to maintain prophase-I arrest in mouse and frog oocytes; acute loss of 4E-T (via TRIM-Away) causes spontaneous meiotic resumption due to untimely translation of c-Mos and cyclin-B1; 4E-T association with eIF4E and PATL2 is critical for target mRNA binding and repression; a POI-associated 4E-T mutant fails to maintain prophase-I arrest in Xenopus oocytes.\",\n      \"method\": \"TRIM-Away acute protein depletion, western blot for c-Mos and cyclin-B1, meiotic maturation assay in mouse and Xenopus oocytes, co-immunoprecipitation of 4E-T with eIF4E and PATL2, mutagenesis\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — fast-acting acute loss-of-function with defined molecular phenotype (meiotic driver derepression), multiple orthogonal methods, two species (mouse and frog), functional mutagenesis\",\n      \"pmids\": [\"40877279\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"EIF4ENIF1 (4E-T) is a nucleocytoplasmic shuttling protein that mediates nuclear import of eIF4E via the importin αβ pathway, localizes to P-bodies where it represses translation and modulates mRNA fate by simultaneously recruiting the CCR4-NOT deadenylase complex (through its middle region), binding eIF4E/4EHP at the 5' cap, and interacting with DDX6 (via its CUP-homology domain), LSM14A, PAT1B, UNR, and CNOT4 to form a multi-protein repressive network; it promotes deadenylation while inhibiting decapping to store mRNAs in a silenced form rather than committing them to degradation, can repress translation both in an eIF4E-dependent (global) and eIF4E-independent (tethered mRNA) manner, undergoes stress-induced phosphorylation by JNK on six proline-directed sites to drive P-body enlargement, and is regulated by ubiquitination (written by TRIM56, erased by OTUD4) and by an intramolecular disulphide bond that reduces eIF4E affinity ~300-fold; in neural progenitors it sequesters proneurogenic mRNAs to balance self-renewal and differentiation, and in oocytes it is essential for maintaining prophase-I arrest by repressing key meiotic drivers such as c-Mos and cyclin-B1.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"EIF4ENIF1 (4E-T) is a translational repressor and mRNA-fate regulator that bridges 5' cap recognition to the 3' decay and storage machinery, partitioning bound transcripts into a silenced rather than degraded state [#8, #12]. It was first defined as a nucleocytoplasmic shuttling protein that mediates piggyback nuclear import of eIF4E via the importin \\u03b1\\u03b2 pathway, carrying a bipartite nuclear localization signal and leucine-rich export signals [#0]. In the cytoplasm 4E-T concentrates in P-bodies, where its eIF4E interaction represses translation and controls mRNA half-life [#1]. Mechanistically, 4E-T scaffolds a repressive ribonucleoprotein network: it binds the 5' cap through eIF4E (and the related 4EHP), engages the DEAD-box helicase DDX6 through its CUP-homology domain in a manner that uniquely tolerates simultaneous CNOT1 binding, and contacts LSM14A, the LSM1-7\\u2013PAT1B complex, UNR, and CNOT4 [#7, #8, #11]. Through sites in its middle region it recruits the CCR4-NOT deadenylase to promote deadenylation while its cap-binding interactions inhibit decapping and degradation, thereby storing transcripts in a deadenylated, repressed form [#12]. 4E-T can silence tethered mRNAs independently of its eIF4E-binding motif and independently of P-body localization, whereas global translational repression and miRNA-mediated decay require eIF4E binding [#5, #8]. Its activity is tuned post-translationally: JNK phosphorylates six proline-directed sites under oxidative stress to drive P-body enlargement and complex assembly [#4], TRIM56 and OTUD4 write and erase ubiquitin to control P-body formation [#13], and a redox-sensitive intramolecular disulphide bond lowers eIF4E affinity ~300-fold [#14]. Biologically, 4E-T sequesters proneurogenic bHLH and transcription-regulator mRNAs in neural precursors to balance self-renewal against differentiation, with its loss causing premature neurogenesis [#6, #15], and it maintains oocyte prophase-I arrest by repressing meiotic drivers c-Mos and cyclin-B1 [#17].\",\n  \"teleology\": [\n    {\n      \"year\": 2000,\n      \"claim\": \"Established the founding molecular role of 4E-T: how the cap-binding protein eIF4E reaches the nucleus, by showing 4E-T is an eIF4E-dependent nuclear import adaptor.\",\n      \"evidence\": \"Co-IP, eIF4E-binding-deficient mutants, leptomycin B and nuclear accumulation assays\",\n      \"pmids\": [\"10856257\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not address cytoplasmic translational functions\", \"Functional consequence of eIF4E nuclear import on gene expression not defined\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Reframed 4E-T as a cytoplasmic mRNA-fate regulator by placing it in P-bodies and linking its eIF4E interaction to translational repression and mRNA stability control.\",\n      \"evidence\": \"siRNA knockdown with mRNA stability assay, fluorescence co-localization, Co-IP\",\n      \"pmids\": [\"16157702\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not resolve whether 4E-T promotes or protects against decay\", \"Repressive partners beyond eIF4E not yet identified\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Showed the repressive complex is context-specific, identifying an oocyte 4E-T network with CPEB, Xp54, Pat1, RAP55 and the oocyte-specific eIF4E1b, with cap-dependent repression not requiring the canonical eIF4E-binding motif.\",\n      \"evidence\": \"Co-IP, gel filtration, pull-downs and tether assays in Xenopus oocytes\",\n      \"pmids\": [\"17942399\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of motif-independent eIF4E1b binding undefined\", \"Direct vs. indirect nature of several interactions not resolved\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Identified stress-responsive regulation of 4E-T, defining JNK phosphorylation of six proline-directed sites as a switch for complex assembly and P-body enlargement.\",\n      \"evidence\": \"Quantitative MS, kinase assay, image-based P-body quantification, polysome profiling, siRNA\",\n      \"pmids\": [\"22966201\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Which target mRNAs are affected by phosphorylation not mapped\", \"Phosphorylation shown not to alter global translation, leaving the functional output narrow\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Dissected the two modes of repression, showing tethered-mRNA silencing is eIF4E-independent and P-body-independent while global repression and miRNA silencing relief require eIF4E binding.\",\n      \"evidence\": \"Tether assay, polysome analysis, eIF4E-binding-motif mutagenesis, qPCR, northern blot\",\n      \"pmids\": [\"24335285\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Effector mediating eIF4E-independent repression not identified\", \"Endogenous target set not defined\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Assigned an in vivo developmental function, showing a 4E-T\\u2013eIF4E1 complex sequesters proneurogenic bHLH mRNAs to maintain neural precursors.\",\n      \"evidence\": \"Co-IP, RNA-IP, shRNA/siRNA with neurogenesis phenotype, granule co-localization\",\n      \"pmids\": [\"25456498\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of mRNA selectivity unclear\", \"Reversibility/derepression trigger during normal differentiation not defined\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Resolved at atomic resolution how 4E-T engages the decay machinery, showing its CUP-homology domain wraps DDX6 and contacts CNOT1, uniquely retaining DDX6 binding when CNOT1 is engaged.\",\n      \"evidence\": \"2.1 \\u00c5 X-ray crystallography, in vitro binding, Co-IP\",\n      \"pmids\": [\"26489469\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional consequence of simultaneous DDX6/CNOT1 engagement on individual mRNAs not measured\", \"Structure of full repressive assembly unresolved\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Defined 4E-T as a cap-to-decay bridge, mapping interactions with eIF4E, DDX6, LSM14 and LSM1-7\\u2013PAT1 and showing eIF4E binding is required for decay of miRNA targets.\",\n      \"evidence\": \"Co-IP, MS interactome, tether and mRNA decay assays, mutagenesis\",\n      \"pmids\": [\"26027925\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Why some 4E-T activities favor decay while others favor storage not reconciled here\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Placed 4E-T epistatically downstream of CCR4-NOT, establishing a CAF1\\u2013CCR4-NOT\\u2013Xp54\\u20134E-T repression chain dependent on eIF4E binding.\",\n      \"evidence\": \"Tether/epistasis assays in Xenopus oocytes, AP-MS, Co-IP, truncation/mutation analysis\",\n      \"pmids\": [\"26015597\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Generality of the chain order outside oocytes not tested\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Linked 4E-T to stress survival, showing phosphomimetic eIF4E requires 4E-T binding to confer resistance to oxidative and DNA-damaging stress.\",\n      \"evidence\": \"Phosphomimetic/phospho-dead eIF4E expression, 4E-T knockdown, eIF4E-W73A mutagenesis, viability and polysome assays\",\n      \"pmids\": [\"25923732\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single lab; downstream survival effectors not identified\", \"Mechanistic link between 4E-T binding and stress resistance unresolved\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Comprehensively mapped the 4E-T interactome to distinct motifs, showing UNR and DDX6 binding sites cooperatively mediate repression and DDX6 binding drives de novo P-body assembly.\",\n      \"evidence\": \"MS, western blot, tether assay, deletion mutagenesis, miRNA reporter and P-body assays\",\n      \"pmids\": [\"27342281\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Stoichiometry and order of assembly of the multi-partner complex not defined\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Reconciled the storage-versus-decay paradox, showing 4E-T promotes deadenylation via middle-region CCR4-NOT recruitment while cap-binding interactions inhibit decapping, storing mRNAs in a deadenylated repressed state.\",\n      \"evidence\": \"Tether assay, CCR4-NOT site mutagenesis, mRNA decay assay, Co-IP, overexpression\",\n      \"pmids\": [\"32354837\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Signals that convert stored mRNAs to degradation or reactivation not defined\", \"In vivo relevance of the storage state across tissues untested here\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Identified ubiquitin as a regulatory layer, with TRIM56 (writer) and OTUD4 (eraser) tuning 4E-T ubiquitination to control P-body assembly and neural progenitor cell-cycle progression.\",\n      \"evidence\": \"DUB/E3 identification, ubiquitination assays, OTUD4/TRIM56 manipulation, P-body and differentiation assays\",\n      \"pmids\": [\"35830814\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Ubiquitinated residues and chain type not defined\", \"Single lab; link between ubiquitination and specific mRNA fate not established\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Defined a redox switch on 4E-T, showing an intramolecular disulphide between the 4E-binding motifs reduces eIF4E affinity ~300-fold.\",\n      \"evidence\": \"Biophysical binding under non-reducing conditions, mutagenesis, affinity measurement\",\n      \"pmids\": [\"37798395\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"In vitro only; cellular evidence that the disulphide forms under physiological oxidation lacking\", \"Functional consequence for mRNA fate not tested\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Extended the neural role transcriptome-wide and in vivo, showing 4E-T associates with ribosome-depleted transcription-regulator mRNAs and is required for NPC maintenance versus differentiation.\",\n      \"evidence\": \"RNA-IP, ribosome profiling, conditional KO and shRNA, in vivo neurogenesis phenotype\",\n      \"pmids\": [\"36924490\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Selectivity determinants for bound mRNAs not defined\", \"Coupling to specific decay/storage outcomes per transcript unresolved\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Connected 4E-T to human fertility disease, showing wild-type represses global translation while POI-associated mutants (Q842P, R208H) fail to repress and derepress fertility-associated transcripts.\",\n      \"evidence\": \"T&T-seq dual-omics with WT and mutant overexpression in 293FT cells\",\n      \"pmids\": [\"38604507\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Heterologous 293FT system, not oocytes\", \"Causal link between specific derepressed transcripts and disease phenotype not established\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Established 4E-T as essential for oocyte prophase-I arrest, showing acute loss triggers meiotic resumption via untimely c-Mos and cyclin-B1 translation, dependent on eIF4E and PATL2 binding.\",\n      \"evidence\": \"TRIM-Away acute depletion, western blot, meiotic maturation assays in mouse and Xenopus, Co-IP, mutagenesis\",\n      \"pmids\": [\"40877279\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Full set of arrest-maintaining target mRNAs not defined\", \"How fertilization/maturation signals relieve 4E-T repression unresolved\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How the multiple regulatory inputs (JNK phosphorylation, TRIM56/OTUD4 ubiquitination, redox disulphide) are integrated to choose between mRNA storage, decay, and reactivation in a tissue-specific manner remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unified model linking the regulatory modifications to specific mRNA-fate outcomes\", \"Determinants of 4E-T target mRNA selectivity unknown\", \"Reactivation/derepression triggers across cell types undefined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0045182\", \"supporting_discovery_ids\": [1, 5, 8, 12, 16, 17]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [0, 7, 8, 11]},\n      {\"term_id\": \"GO:0140313\", \"supporting_discovery_ids\": [12, 6, 15]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [12, 9]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [1, 4, 11]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-8953854\", \"supporting_discovery_ids\": [1, 8, 12]},\n      {\"term_id\": \"R-HSA-72766\", \"supporting_discovery_ids\": [5]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [6, 15]},\n      {\"term_id\": \"R-HSA-1474165\", \"supporting_discovery_ids\": [17]}\n    ],\n    \"complexes\": [\n      \"P-body\",\n      \"CCR4-NOT (recruited)\",\n      \"4E-T\\u2013eIF4E repressive complex\",\n      \"LSM1-7\\u2013PAT1 complex (associated)\"\n    ],\n    \"partners\": [\n      \"EIF4E\",\n      \"DDX6\",\n      \"LSM14A\",\n      \"PATL2\",\n      \"CNOT1\",\n      \"UNR\",\n      \"CNOT4\",\n      \"EIF4E1B\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}