{"gene":"ELOA","run_date":"2026-06-09T23:54:43","timeline":{"discoveries":[{"year":2003,"finding":"Elongin A (ELOA) NH2-terminal ~120 amino acid region binds a novel exonuclease domain-containing protein EloA-BP1, as demonstrated by yeast two-hybrid screening and in vitro binding assay; ELOA and EloA-BP1 co-localize in the cell nucleus by double immunofluorescence.","method":"Yeast two-hybrid, in vitro binding assay, double immunofluorescence in COS7 cells","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — yeast two-hybrid plus in vitro binding plus co-localization, single lab, multiple orthogonal methods but no functional reconstitution","pmids":["12943681"],"is_preprint":false},{"year":2022,"finding":"ELOA protein stability is regulated by Trim21-mediated ubiquitination and degradation; lncRNA DLGAP1-AS2 physically interacts with ELOA and promotes its Trim21-dependent ubiquitination and proteasomal degradation, thereby reducing ELOA protein levels.","method":"RNA pull-down, RNA immunoprecipitation, rescue experiments, ubiquitination assay","journal":"Molecular cancer","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — co-immunoprecipitation and RNA pull-down plus rescue experiments, single lab, multiple methods but no in vitro reconstitution of ubiquitination","pmids":["36376892"],"is_preprint":false},{"year":2022,"finding":"ELOA functions as a transcriptional activator of the LHPP gene promoter; loss of ELOA (via DLGAP1-AS2-mediated degradation) reduces LHPP expression and consequently activates AKT signaling in colorectal cancer cells.","method":"Chromatin immunoprecipitation (ChIP), luciferase assay, RNA sequencing, rescue experiments","journal":"Molecular cancer","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP plus luciferase reporter plus rescue epistasis, single lab, multiple orthogonal methods","pmids":["36376892"],"is_preprint":false},{"year":2021,"finding":"ELOA promotes PMA-induced polyploidization of HEL megakaryocytic cells through enhancement of ERK1/2 phosphorylation activity; knockdown of ELOA impairs polyploidization and reduces ERK1/2 cascade gene transcription, and partial restoration requires ELOA mutants retaining Pol II elongation activity.","method":"shRNA knockdown, RNA-seq, Western blot for ERK1/2 phosphorylation, pharmacological inhibition (PD0325901, SCH772984), overexpression of ELOA mutants","journal":"Platelets","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — knockdown with defined phenotypic readout plus mutant rescue plus pathway inhibitor epistasis, single lab, multiple orthogonal methods","pmids":["34697988"],"is_preprint":false},{"year":2023,"finding":"ELOA transcriptionally activates retinol-binding protein 1 (RBP1) by binding to its promoter in gastric cancer cells; specific knockdown of RBP1 reduces the tumor-promoting effects of ELOA, placing RBP1 downstream of ELOA.","method":"RNA-seq, chromatin immunoprecipitation (ChIP), dual luciferase reporter assay, rescue experiments (RBP1 knockdown)","journal":"Cancer medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP plus luciferase reporter plus epistasis rescue, single lab, multiple orthogonal methods","pmids":["37694492"],"is_preprint":false},{"year":2024,"finding":"ELOA (TCEB3) functions as an E3 ligase recognition subunit targeting MCL-1 for ubiquitination and degradation in the cytoplasm during platinum treatment in ovarian cancer cells; platinum treatment increases the cytoplasmic proportion of ELOA, and cytoplasmic localization is required for ELOA to target MCL-1.","method":"Ubiquitination assay, subcellular fractionation, Western blot, knockdown/overexpression experiments","journal":"FASEB journal","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — ubiquitination assay plus fractionation plus functional KD/OE, single lab, multiple methods but no in vitro reconstitution of E3 activity","pmids":["38661028"],"is_preprint":false},{"year":2025,"finding":"ELOA occupies transcription end site (TES)-proximal regions under normal conditions; acute depletion of ELOA reduces RNA polymerase II processivity at the 3' end of genes. ELOA loss suppresses the progression of RNAPII past TESs at NELF depletion-induced genes. Genetic suppressor screens placed ELOA downstream of NELF/SPT6 depletion-induced growth arrest and pre-mRNA processing defects.","method":"Auxin-inducible degron (acute depletion), long- and short-read RNA-seq, RNAPII ChIP-seq, genetic suppressor screen, ELOA knockout","journal":"Molecular cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — auxin-inducible degron acute depletion plus RNAPII occupancy mapping plus genetic suppressor screen plus KO, peer-reviewed, multiple orthogonal methods in one rigorous study","pmids":["41418754"],"is_preprint":false},{"year":2025,"finding":"ELOA loss confers a growth advantage to aging primary human dermal fibroblasts, linking ELOA-dependent transcriptional elongation/RNA processing mechanisms to cellular senescence and aging.","method":"ELOA genetic knockout in primary human dermal fibroblasts, growth assays","journal":"Molecular cell","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — KO with defined growth phenotype in primary cells, single lab, single functional readout","pmids":["41418754"],"is_preprint":false},{"year":2025,"finding":"ELOA binds the RPB1 jaw domain of RNA polymerase II, competing with IWS1 for occupancy; IWS1 protects the activated transcription elongation complex from RECQL5 inhibition, and ELOA is identified as one of several elongation factors that bind the RPB1 jaw.","method":"Cryo-electron microscopy structural mapping, functional transcription assays, binding competition experiments","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — cryo-EM structure plus functional assays, but ELOA finding is secondary/ancillary to the IWS1 paper and is a preprint","pmids":["bio_10.1101_2025.08.28.672863"],"is_preprint":true}],"current_model":"ELOA (Elongin A) is the transcriptionally active subunit of the Elongin complex that stimulates RNA polymerase II elongation by suppressing transient pausing; it occupies TES-proximal chromatin to maintain RNAPII processivity at the 3' end of genes, binds the RPB1 jaw domain of RNAPII, transcriptionally activates target gene promoters (e.g., LHPP, RBP1) via direct promoter binding, can localize to the cytoplasm under stress where it acts as an E3 ligase recognition subunit to ubiquitinate and degrade MCL-1, and is itself subject to Trim21-mediated ubiquitination/degradation promoted by interaction with lncRNA DLGAP1-AS2; ELOA also promotes megakaryocytic polyploidization through enhanced ERK1/2 activity, and its loss suppresses NELF/SPT6 depletion-induced senescence-associated transcriptional changes while conferring a growth advantage to aging primary fibroblasts."},"narrative":{"mechanistic_narrative":"ELOA (Elongin A) is a transcription elongation factor that sustains RNA polymerase II (RNAPII) processivity, particularly across the 3' ends of genes [PMID:41418754]. ELOA occupies transcription end site (TES)-proximal chromatin, and its acute depletion reduces RNAPII processivity at gene 3' ends and curtails progression of RNAPII past TESs; genetic suppressor screens place ELOA downstream of NELF/SPT6 depletion-induced growth arrest and pre-mRNA processing defects [PMID:41418754]. Structurally, ELOA engages the RPB1 jaw domain of RNAPII, competing with IWS1 for this site [PMID:bio_10.1101_2025.08.28.672863]. Beyond its core elongation role, ELOA acts as a sequence-directed transcriptional activator at specific promoters, binding and activating the LHPP and RBP1 promoters; loss of LHPP activation downstream of ELOA degradation derepresses AKT signaling in colorectal cancer cells, while RBP1 mediates ELOA's tumor-promoting effect in gastric cancer [PMID:36376892, PMID:37694492]. ELOA protein abundance is controlled by Trim21-mediated ubiquitination and proteasomal degradation, an event promoted by physical interaction with the lncRNA DLGAP1-AS2 [PMID:36376892]. ELOA additionally has a context-dependent cytoplasmic function: during platinum treatment in ovarian cancer cells its cytoplasmic pool increases and it serves as an E3 ligase recognition subunit targeting MCL-1 for ubiquitination and degradation [PMID:38661028]. Functionally, ELOA promotes PMA-induced megakaryocytic polyploidization through enhanced ERK1/2 phosphorylation, a phenotype requiring its RNAPII elongation activity [PMID:34697988], and its loss confers a growth advantage to aging primary fibroblasts, linking ELOA-dependent elongation/processing to senescence [PMID:41418754].","teleology":[{"year":2003,"claim":"Established an early physical interaction partner for ELOA, identifying its N-terminal region as a protein-binding module engaging an exonuclease domain-containing protein in the nucleus.","evidence":"Yeast two-hybrid, in vitro binding, and double immunofluorescence in COS7 cells","pmids":["12943681"],"confidence":"Medium","gaps":["Functional consequence of the ELOA–EloA-BP1 interaction not reconstituted","No link drawn to ELOA's elongation or ubiquitination roles","Interaction shown in heterologous systems only"]},{"year":2021,"claim":"Connected ELOA's elongation activity to a cellular differentiation phenotype, showing it drives megakaryocytic polyploidization via the ERK1/2 cascade.","evidence":"shRNA knockdown, RNA-seq, ERK1/2 phospho-Western, MEK/ERK inhibitors, and elongation-competent ELOA mutant rescue in HEL cells","pmids":["34697988"],"confidence":"Medium","gaps":["Direct ELOA targets within the ERK1/2 cascade not defined","Mechanism linking Pol II elongation to ERK activation unresolved","Single cell-line model"]},{"year":2022,"claim":"Defined ELOA as a promoter-binding transcriptional activator and revealed how its degradation rewires oncogenic signaling, with lncRNA-directed Trim21 ubiquitination controlling its levels.","evidence":"ChIP, luciferase reporter, RNA-seq, RNA pull-down/RIP, ubiquitination and rescue assays in colorectal cancer cells","pmids":["36376892"],"confidence":"Medium","gaps":["In vitro reconstitution of Trim21-mediated ubiquitination not performed","Direct vs. indirect promoter binding to LHPP not structurally resolved","Generality of DLGAP1-AS2 regulation beyond CRC unknown"]},{"year":2023,"claim":"Extended ELOA's promoter-activator role to a second target gene, RBP1, in a distinct cancer context.","evidence":"RNA-seq, ChIP, dual luciferase reporter, and RBP1-knockdown epistasis in gastric cancer cells","pmids":["37694492"],"confidence":"Medium","gaps":["Whether RBP1 activation reflects direct elongation enhancement or specific recruitment is unclear","No structural basis for promoter selectivity"]},{"year":2024,"claim":"Revealed a non-transcriptional, cytoplasmic moonlighting function for ELOA as an E3 ligase recognition subunit targeting MCL-1 under genotoxic stress.","evidence":"Ubiquitination assay, subcellular fractionation, Western blot, knockdown/overexpression during platinum treatment in ovarian cancer cells","pmids":["38661028"],"confidence":"Medium","gaps":["E3 activity not reconstituted in vitro","Trigger and machinery for ELOA cytoplasmic relocalization undefined","Whether MCL-1 is a direct ELOA substrate not structurally shown"]},{"year":2025,"claim":"Pinned down ELOA's core mechanism as a TES-proximal factor maintaining RNAPII processivity at gene 3' ends and placed it genetically downstream of NELF/SPT6, also linking its loss to senescence.","evidence":"Auxin-inducible degron acute depletion, long/short-read RNA-seq, RNAPII ChIP-seq, genetic suppressor screen, and knockout in primary fibroblasts","pmids":["41418754"],"confidence":"High","gaps":["Molecular basis of TES-proximal recruitment not fully resolved","How processivity defects translate into senescence outcomes unclear"]},{"year":2025,"claim":"Provided a structural anchor point for ELOA on the elongation complex, showing it binds the RPB1 jaw domain in competition with IWS1.","evidence":"Cryo-EM structural mapping and binding competition assays (preprint)","pmids":["bio_10.1101_2025.08.28.672863"],"confidence":"Medium","gaps":["ELOA finding is ancillary to an IWS1-focused study and is a preprint","Functional consequence of ELOA–IWS1 competition for ELOA-specific roles not established"]},{"year":null,"claim":"How ELOA's distinct activities — core elongation processivity, promoter-specific activation, and cytoplasmic E3 substrate recognition — are mechanistically partitioned and coordinated remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unified model linking nuclear elongation and cytoplasmic ubiquitination roles","Determinants of ELOA promoter selectivity unknown","Signals controlling nuclear vs. cytoplasmic partitioning undefined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140110","term_label":"transcription regulator activity","supporting_discovery_ids":[2,4,6]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[5]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0,6]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[5]}],"pathway":[{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[2,4,6]}],"complexes":["Elongin complex"],"partners":["RPB1/POLR2A","IWS1","TRIM21","DLGAP1-AS2","MCL-1","ELOA-BP1"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q14241","full_name":"Elongin-A","aliases":["Elongin 110 kDa subunit","RNA polymerase II transcription factor SIII subunit A1","SIII p110","Transcription elongation factor B polypeptide 3"],"length_aa":772,"mass_kda":87.2,"function":"SIII, also known as elongin, is a general transcription elongation factor that increases the RNA polymerase II transcription elongation past template-encoded arresting sites. Subunit A is transcriptionally active and its transcription activity is strongly enhanced by binding to the dimeric complex of the SIII regulatory subunits B and C (elongin BC complex) As part of a multisubunit complex composed of elongin BC complex (ELOB and ELOC), elongin A/ELOA, RBX1 and CUL5; polyubiquitinates monoubiquitinated POLR2A","subcellular_location":"Nucleus","url":"https://www.uniprot.org/uniprotkb/Q14241/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/ELOA","classification":"Not Classified","n_dependent_lines":155,"n_total_lines":1208,"dependency_fraction":0.12831125827814568},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/ELOA","total_profiled":1310},"omim":[{"mim_id":"609614","title":"RNA EXONUCLEASE 1 HOMOLOG; REXO1","url":"https://www.omim.org/entry/609614"},{"mim_id":"609522","title":"ELONGIN A2; ELOA2","url":"https://www.omim.org/entry/609522"},{"mim_id":"608537","title":"VON HIPPEL-LINDAU TUMOR SUPPRESSOR; VHL","url":"https://www.omim.org/entry/608537"},{"mim_id":"607305","title":"MDS2 GENE","url":"https://www.omim.org/entry/607305"},{"mim_id":"600788","title":"ELONGIN C; ELOC","url":"https://www.omim.org/entry/600788"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Nuclear speckles","reliability":"Approved"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in many","driving_tissues":[],"url":"https://www.proteinatlas.org/search/ELOA"},"hgnc":{"alias_symbol":["SIII","TCEB3A","ELOA1"],"prev_symbol":["TCEB3"]},"alphafold":{"accession":"Q14241","domains":[{"cath_id":"-","chopping":"33-102","consensus_level":"high","plddt":89.9633,"start":33,"end":102},{"cath_id":"-","chopping":"578-677","consensus_level":"high","plddt":91.1961,"start":578,"end":677}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q14241","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q14241-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q14241-F1-predicted_aligned_error_v6.png","plddt_mean":57.03},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=ELOA","jax_strain_url":"https://www.jax.org/strain/search?query=ELOA"},"sequence":{"accession":"Q14241","fasta_url":"https://rest.uniprot.org/uniprotkb/Q14241.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q14241/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q14241"}},"corpus_meta":[{"pmid":"36376892","id":"PMC_36376892","title":"Long noncoding RNA DLGAP1-AS2 promotes tumorigenesis and metastasis by regulating the Trim21/ELOA/LHPP axis in colorectal cancer.","date":"2022","source":"Molecular cancer","url":"https://pubmed.ncbi.nlm.nih.gov/36376892","citation_count":46,"is_preprint":false},{"pmid":"20735022","id":"PMC_20735022","title":"Lipoprotein complex of equine lysozyme with oleic acid (ELOA) interactions with the plasma membrane of live cells.","date":"2010","source":"Langmuir : the ACS journal of surfaces and colloids","url":"https://pubmed.ncbi.nlm.nih.gov/20735022","citation_count":22,"is_preprint":false},{"pmid":"12943681","id":"PMC_12943681","title":"Identification of EloA-BP1, a novel Elongin A binding protein with an exonuclease homology domain.","date":"2003","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/12943681","citation_count":10,"is_preprint":false},{"pmid":"33953570","id":"PMC_33953570","title":"TCEB3 is Regulated by Circ-0000212/miR-140-3p Axis to Promote the Progression of Cervical Cancer.","date":"2021","source":"OncoTargets and therapy","url":"https://pubmed.ncbi.nlm.nih.gov/33953570","citation_count":9,"is_preprint":false},{"pmid":"10575222","id":"PMC_10575222","title":"Structural organization and chromosome location of the mouse elongin A gene (Tceb3).","date":"1999","source":"Cytogenetics and cell genetics","url":"https://pubmed.ncbi.nlm.nih.gov/10575222","citation_count":6,"is_preprint":false},{"pmid":"37694492","id":"PMC_37694492","title":"ELOA promotes tumor growth and metastasis by activating RBP1 in gastric cancer.","date":"2023","source":"Cancer medicine","url":"https://pubmed.ncbi.nlm.nih.gov/37694492","citation_count":4,"is_preprint":false},{"pmid":"34697988","id":"PMC_34697988","title":"EloA promotes HEL polyploidization upon PMA stimulation through enhanced ERK1/2 activity.","date":"2021","source":"Platelets","url":"https://pubmed.ncbi.nlm.nih.gov/34697988","citation_count":3,"is_preprint":false},{"pmid":"38661028","id":"PMC_38661028","title":"TCEB3 initiates ovarian cancer apoptosis by mediating ubiquitination and degradation of MCL-1.","date":"2024","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/38661028","citation_count":2,"is_preprint":false},{"pmid":"41418754","id":"PMC_41418754","title":"Defective RNA processing and ELOA-mediated transcriptional elongation in reversible cellular senescence suggest aging by transcription.","date":"2025","source":"Molecular cell","url":"https://pubmed.ncbi.nlm.nih.gov/41418754","citation_count":0,"is_preprint":false},{"pmid":"39781562","id":"PMC_39781562","title":"Tumor-Educated Platelets lncRNA-STARD4-AS1 and ELOA-AS1 as Potential Novel Biomarkers for the Early Diagnosis of Non-Small Cell Lung Cancer.","date":"2025","source":"Cancer management and research","url":"https://pubmed.ncbi.nlm.nih.gov/39781562","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.06.23.660200","title":"Transcriptional Elongation-Associated RNA Processing Errors in Induced Cellular Growth Arrest","date":"2025-06-23","source":"bioRxiv","url":"https://doi.org/10.1101/2025.06.23.660200","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.08.28.672863","title":"Structure and function of IWS1 in transcription elongation","date":"2025-08-28","source":"bioRxiv","url":"https://doi.org/10.1101/2025.08.28.672863","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":8203,"output_tokens":2256,"usd":0.029225,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":9355,"output_tokens":2907,"usd":0.059725,"stage2_stop_reason":"end_turn"},"total_usd":0.08895,"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\": 2003,\n      \"finding\": \"Elongin A (ELOA) NH2-terminal ~120 amino acid region binds a novel exonuclease domain-containing protein EloA-BP1, as demonstrated by yeast two-hybrid screening and in vitro binding assay; ELOA and EloA-BP1 co-localize in the cell nucleus by double immunofluorescence.\",\n      \"method\": \"Yeast two-hybrid, in vitro binding assay, double immunofluorescence in COS7 cells\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — yeast two-hybrid plus in vitro binding plus co-localization, single lab, multiple orthogonal methods but no functional reconstitution\",\n      \"pmids\": [\"12943681\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"ELOA protein stability is regulated by Trim21-mediated ubiquitination and degradation; lncRNA DLGAP1-AS2 physically interacts with ELOA and promotes its Trim21-dependent ubiquitination and proteasomal degradation, thereby reducing ELOA protein levels.\",\n      \"method\": \"RNA pull-down, RNA immunoprecipitation, rescue experiments, ubiquitination assay\",\n      \"journal\": \"Molecular cancer\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — co-immunoprecipitation and RNA pull-down plus rescue experiments, single lab, multiple methods but no in vitro reconstitution of ubiquitination\",\n      \"pmids\": [\"36376892\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"ELOA functions as a transcriptional activator of the LHPP gene promoter; loss of ELOA (via DLGAP1-AS2-mediated degradation) reduces LHPP expression and consequently activates AKT signaling in colorectal cancer cells.\",\n      \"method\": \"Chromatin immunoprecipitation (ChIP), luciferase assay, RNA sequencing, rescue experiments\",\n      \"journal\": \"Molecular cancer\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP plus luciferase reporter plus rescue epistasis, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"36376892\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"ELOA promotes PMA-induced polyploidization of HEL megakaryocytic cells through enhancement of ERK1/2 phosphorylation activity; knockdown of ELOA impairs polyploidization and reduces ERK1/2 cascade gene transcription, and partial restoration requires ELOA mutants retaining Pol II elongation activity.\",\n      \"method\": \"shRNA knockdown, RNA-seq, Western blot for ERK1/2 phosphorylation, pharmacological inhibition (PD0325901, SCH772984), overexpression of ELOA mutants\",\n      \"journal\": \"Platelets\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — knockdown with defined phenotypic readout plus mutant rescue plus pathway inhibitor epistasis, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"34697988\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"ELOA transcriptionally activates retinol-binding protein 1 (RBP1) by binding to its promoter in gastric cancer cells; specific knockdown of RBP1 reduces the tumor-promoting effects of ELOA, placing RBP1 downstream of ELOA.\",\n      \"method\": \"RNA-seq, chromatin immunoprecipitation (ChIP), dual luciferase reporter assay, rescue experiments (RBP1 knockdown)\",\n      \"journal\": \"Cancer medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP plus luciferase reporter plus epistasis rescue, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"37694492\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"ELOA (TCEB3) functions as an E3 ligase recognition subunit targeting MCL-1 for ubiquitination and degradation in the cytoplasm during platinum treatment in ovarian cancer cells; platinum treatment increases the cytoplasmic proportion of ELOA, and cytoplasmic localization is required for ELOA to target MCL-1.\",\n      \"method\": \"Ubiquitination assay, subcellular fractionation, Western blot, knockdown/overexpression experiments\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — ubiquitination assay plus fractionation plus functional KD/OE, single lab, multiple methods but no in vitro reconstitution of E3 activity\",\n      \"pmids\": [\"38661028\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"ELOA occupies transcription end site (TES)-proximal regions under normal conditions; acute depletion of ELOA reduces RNA polymerase II processivity at the 3' end of genes. ELOA loss suppresses the progression of RNAPII past TESs at NELF depletion-induced genes. Genetic suppressor screens placed ELOA downstream of NELF/SPT6 depletion-induced growth arrest and pre-mRNA processing defects.\",\n      \"method\": \"Auxin-inducible degron (acute depletion), long- and short-read RNA-seq, RNAPII ChIP-seq, genetic suppressor screen, ELOA knockout\",\n      \"journal\": \"Molecular cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — auxin-inducible degron acute depletion plus RNAPII occupancy mapping plus genetic suppressor screen plus KO, peer-reviewed, multiple orthogonal methods in one rigorous study\",\n      \"pmids\": [\"41418754\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"ELOA loss confers a growth advantage to aging primary human dermal fibroblasts, linking ELOA-dependent transcriptional elongation/RNA processing mechanisms to cellular senescence and aging.\",\n      \"method\": \"ELOA genetic knockout in primary human dermal fibroblasts, growth assays\",\n      \"journal\": \"Molecular cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — KO with defined growth phenotype in primary cells, single lab, single functional readout\",\n      \"pmids\": [\"41418754\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"ELOA binds the RPB1 jaw domain of RNA polymerase II, competing with IWS1 for occupancy; IWS1 protects the activated transcription elongation complex from RECQL5 inhibition, and ELOA is identified as one of several elongation factors that bind the RPB1 jaw.\",\n      \"method\": \"Cryo-electron microscopy structural mapping, functional transcription assays, binding competition experiments\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — cryo-EM structure plus functional assays, but ELOA finding is secondary/ancillary to the IWS1 paper and is a preprint\",\n      \"pmids\": [\"bio_10.1101_2025.08.28.672863\"],\n      \"is_preprint\": true\n    }\n  ],\n  \"current_model\": \"ELOA (Elongin A) is the transcriptionally active subunit of the Elongin complex that stimulates RNA polymerase II elongation by suppressing transient pausing; it occupies TES-proximal chromatin to maintain RNAPII processivity at the 3' end of genes, binds the RPB1 jaw domain of RNAPII, transcriptionally activates target gene promoters (e.g., LHPP, RBP1) via direct promoter binding, can localize to the cytoplasm under stress where it acts as an E3 ligase recognition subunit to ubiquitinate and degrade MCL-1, and is itself subject to Trim21-mediated ubiquitination/degradation promoted by interaction with lncRNA DLGAP1-AS2; ELOA also promotes megakaryocytic polyploidization through enhanced ERK1/2 activity, and its loss suppresses NELF/SPT6 depletion-induced senescence-associated transcriptional changes while conferring a growth advantage to aging primary fibroblasts.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"ELOA (Elongin A) is a transcription elongation factor that sustains RNA polymerase II (RNAPII) processivity, particularly across the 3' ends of genes [#6]. ELOA occupies transcription end site (TES)-proximal chromatin, and its acute depletion reduces RNAPII processivity at gene 3' ends and curtails progression of RNAPII past TESs; genetic suppressor screens place ELOA downstream of NELF/SPT6 depletion-induced growth arrest and pre-mRNA processing defects [#6]. Structurally, ELOA engages the RPB1 jaw domain of RNAPII, competing with IWS1 for this site [#8]. Beyond its core elongation role, ELOA acts as a sequence-directed transcriptional activator at specific promoters, binding and activating the LHPP and RBP1 promoters; loss of LHPP activation downstream of ELOA degradation derepresses AKT signaling in colorectal cancer cells, while RBP1 mediates ELOA's tumor-promoting effect in gastric cancer [#2, #4]. ELOA protein abundance is controlled by Trim21-mediated ubiquitination and proteasomal degradation, an event promoted by physical interaction with the lncRNA DLGAP1-AS2 [#1]. ELOA additionally has a context-dependent cytoplasmic function: during platinum treatment in ovarian cancer cells its cytoplasmic pool increases and it serves as an E3 ligase recognition subunit targeting MCL-1 for ubiquitination and degradation [#5]. Functionally, ELOA promotes PMA-induced megakaryocytic polyploidization through enhanced ERK1/2 phosphorylation, a phenotype requiring its RNAPII elongation activity [#3], and its loss confers a growth advantage to aging primary fibroblasts, linking ELOA-dependent elongation/processing to senescence [#7].\",\n  \"teleology\": [\n    {\n      \"year\": 2003,\n      \"claim\": \"Established an early physical interaction partner for ELOA, identifying its N-terminal region as a protein-binding module engaging an exonuclease domain-containing protein in the nucleus.\",\n      \"evidence\": \"Yeast two-hybrid, in vitro binding, and double immunofluorescence in COS7 cells\",\n      \"pmids\": [\"12943681\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional consequence of the ELOA\\u2013EloA-BP1 interaction not reconstituted\", \"No link drawn to ELOA's elongation or ubiquitination roles\", \"Interaction shown in heterologous systems only\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Connected ELOA's elongation activity to a cellular differentiation phenotype, showing it drives megakaryocytic polyploidization via the ERK1/2 cascade.\",\n      \"evidence\": \"shRNA knockdown, RNA-seq, ERK1/2 phospho-Western, MEK/ERK inhibitors, and elongation-competent ELOA mutant rescue in HEL cells\",\n      \"pmids\": [\"34697988\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct ELOA targets within the ERK1/2 cascade not defined\", \"Mechanism linking Pol II elongation to ERK activation unresolved\", \"Single cell-line model\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Defined ELOA as a promoter-binding transcriptional activator and revealed how its degradation rewires oncogenic signaling, with lncRNA-directed Trim21 ubiquitination controlling its levels.\",\n      \"evidence\": \"ChIP, luciferase reporter, RNA-seq, RNA pull-down/RIP, ubiquitination and rescue assays in colorectal cancer cells\",\n      \"pmids\": [\"36376892\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"In vitro reconstitution of Trim21-mediated ubiquitination not performed\", \"Direct vs. indirect promoter binding to LHPP not structurally resolved\", \"Generality of DLGAP1-AS2 regulation beyond CRC unknown\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Extended ELOA's promoter-activator role to a second target gene, RBP1, in a distinct cancer context.\",\n      \"evidence\": \"RNA-seq, ChIP, dual luciferase reporter, and RBP1-knockdown epistasis in gastric cancer cells\",\n      \"pmids\": [\"37694492\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether RBP1 activation reflects direct elongation enhancement or specific recruitment is unclear\", \"No structural basis for promoter selectivity\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Revealed a non-transcriptional, cytoplasmic moonlighting function for ELOA as an E3 ligase recognition subunit targeting MCL-1 under genotoxic stress.\",\n      \"evidence\": \"Ubiquitination assay, subcellular fractionation, Western blot, knockdown/overexpression during platinum treatment in ovarian cancer cells\",\n      \"pmids\": [\"38661028\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"E3 activity not reconstituted in vitro\", \"Trigger and machinery for ELOA cytoplasmic relocalization undefined\", \"Whether MCL-1 is a direct ELOA substrate not structurally shown\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Pinned down ELOA's core mechanism as a TES-proximal factor maintaining RNAPII processivity at gene 3' ends and placed it genetically downstream of NELF/SPT6, also linking its loss to senescence.\",\n      \"evidence\": \"Auxin-inducible degron acute depletion, long/short-read RNA-seq, RNAPII ChIP-seq, genetic suppressor screen, and knockout in primary fibroblasts\",\n      \"pmids\": [\"41418754\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular basis of TES-proximal recruitment not fully resolved\", \"How processivity defects translate into senescence outcomes unclear\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Provided a structural anchor point for ELOA on the elongation complex, showing it binds the RPB1 jaw domain in competition with IWS1.\",\n      \"evidence\": \"Cryo-EM structural mapping and binding competition assays (preprint)\",\n      \"pmids\": [\"bio_10.1101_2025.08.28.672863\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"ELOA finding is ancillary to an IWS1-focused study and is a preprint\", \"Functional consequence of ELOA\\u2013IWS1 competition for ELOA-specific roles not established\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How ELOA's distinct activities \\u2014 core elongation processivity, promoter-specific activation, and cytoplasmic E3 substrate recognition \\u2014 are mechanistically partitioned and coordinated remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unified model linking nuclear elongation and cytoplasmic ubiquitination roles\", \"Determinants of ELOA promoter selectivity unknown\", \"Signals controlling nuclear vs. cytoplasmic partitioning undefined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140110\", \"supporting_discovery_ids\": [2, 4, 6]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [5]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0, 6]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [5]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [2, 4, 6]}\n    ],\n    \"complexes\": [\"Elongin complex\"],\n    \"partners\": [\"RPB1/POLR2A\", \"IWS1\", \"Trim21\", \"DLGAP1-AS2\", \"MCL-1\", \"EloA-BP1\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}