{"gene":"E2F2","run_date":"2026-06-09T23:54:42","timeline":{"discoveries":[{"year":1993,"finding":"E2F2 (E2F-2) was cloned and found to share 46% amino acid identity with E2F1. The DNA binding domain and retinoblastoma (Rb) protein binding domain functions are conserved. E2F2 DNA binding activity is dramatically enhanced by complementation with HeLa cell E2F components, consistent with E2F binding DNA as a heterodimer, and anti-E2F-2 antibodies cross-react with purified HeLa cell E2F.","method":"cDNA cloning, DNA binding assays, antibody cross-reactivity, complementation assays with SDS-PAGE-purified HeLa cell E2F components","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro DNA binding assays, domain functional validation, and biochemical complementation; foundational characterization paper","pmids":["8246995"],"is_preprint":false},{"year":1997,"finding":"The E2F2 promoter contains E-box elements that function as Myc-responsive activation sites and E2F binding sites that mediate negative (repressive) regulation in quiescent cells. Both elements contribute to the cell-growth-dependent control of E2F2 expression, similar to regulation of the E2F1 gene promoter.","method":"Promoter reporter assays, deletion/mutation analysis, growth stimulation experiments","journal":"Molecular and cellular biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — promoter-reporter assays with deletion mutants in multiple conditions, single lab","pmids":["9271400"],"is_preprint":false},{"year":2001,"finding":"E2F2 is required for immunologic self-tolerance. E2F2-deficient T lymphocytes exhibit enhanced TCR-stimulated proliferation and a lower activation threshold. Rather than functioning as a transcriptional activator, E2F2 appears to function as a transcriptional repressor of genes required for S phase entry, particularly E2F1.","method":"E2f2 knockout mice, T cell proliferation assays, TCR stimulation, immunophenotyping","journal":"Immunity","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic knockout with defined cellular phenotype (enhanced T cell proliferation and autoimmunity), replicated across multiple assays","pmids":["11754817"],"is_preprint":false},{"year":2001,"finding":"Combined loss of E2F1 and E2F2 results in profound effects on hematopoietic cell proliferation, B-cell differentiation, and T-cell tolerance/proliferation thresholds. E2F1/E2F2 double-knockout T cells exhibit more rapid entry into S phase and extensive proliferation in response to subthreshold antigenic stimulation, and double-knockout mice are highly predisposed to tumor development.","method":"E2f1/E2f2 double-knockout mice, cell cycle analysis, antigenic stimulation, tumor monitoring","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic double knockout with multiple orthogonal phenotypic readouts (proliferation, differentiation, tumorigenesis)","pmids":["11713289"],"is_preprint":false},{"year":2001,"finding":"Drosophila E2f2 loss is viable but causes female sterility associated with failure to confine DNA synthesis to gene amplification sites in follicle cells. E2f2 mutant follicle cells inappropriately initiate genomic DNA replication instead of restricting synthesis to chorion gene amplification loci. Replication proteins ORC2, CDC45L, and ORC5 redistribute throughout the nucleus in E2f2 mutants. RT-PCR showed increased Orc5 mRNA in E2f2 mutants, indicating E2f2 represses pre-RC gene expression.","method":"Drosophila E2f2 mutant genetics, BrdU incorporation, immunofluorescence localization of ORC2/CDC45L/ORC5, RT-PCR","journal":"Development (Cambridge, England)","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic loss-of-function with multiple orthogonal assays (replication, immunofluorescence localization, RT-PCR), Drosophila ortholog","pmids":["11748144"],"is_preprint":false},{"year":2001,"finding":"Forced expression of E2F2 in PC12 cells (neuronal differentiation model) inhibited dedifferentiation and cell cycle re-entry upon NGF removal, and induced apoptosis instead. E2F2 converted reversibly differentiated neurons to a terminally differentiated, NGF-dependent state. Endogenous E2F2 levels increase in PC12 cells in response to NGF.","method":"Gain-of-function E2F2 overexpression in PC12 cells, NGF removal assay, cell cycle re-entry assays, apoptosis assays","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — gain-of-function with defined phenotype (blocked dedifferentiation, induced apoptosis), single lab","pmids":["11526501"],"is_preprint":false},{"year":2002,"finding":"E2F1, E2F2, and E2F3 each contribute individually to Rb-deficiency-induced unscheduled proliferation in vivo. In the developing lens and retina of Rb-/- embryos, loss of E2F2 reduces ectopic DNA replication. E2F2 loss partially reduces unscheduled DNA replication in the CNS but has no effect on apoptosis in Rb-null embryos, demonstrating functional specificity among E2Fs.","method":"Compound Rb/E2f knockout mice, BrdU incorporation (ectopic proliferation), TUNEL (apoptosis), tissue-specific analysis","journal":"Cell growth & differentiation","confidence":"High","confidence_rationale":"Tier 2 / Strong — compound genetic knockouts across multiple tissues with multiple phenotypic readouts","pmids":["12065245"],"is_preprint":false},{"year":2002,"finding":"E2F2 and E2F3 can transcriptionally activate the p14(ARF) promoter, even in the absence of consensus E2F binding sites. Deletion and site-directed mutagenesis indicate E2F can regulate ARF both by direct DNA binding and indirectly, possibly via tethering by Sp1-like factors.","method":"Transient transfection reporter assays, promoter deletion and site-directed mutagenesis","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reporter assays with mutants in multiple conditions; single lab, one method type","pmids":["11883935"],"is_preprint":false},{"year":2002,"finding":"ARF induction in response to oncogenic Ras and viral E1A oncoprotein is not significantly affected in E2F1-/-, E2F2-/-, or E2F1/2 double-knockout MEFs. ARF is upregulated normally in all cases, indicating ARF activation by oncogenic stress can occur by E2F1- and E2F2-independent mechanisms.","method":"Primary E2f1/E2f2 knockout MEFs, oncogenic Ras/E1A overexpression, ARF western blot and transcription assays","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic knockouts with oncogene induction; this is a negative result (ARF is NOT regulated by E2F2 in this context), single lab","pmids":["12082524"],"is_preprint":false},{"year":2003,"finding":"E2F-2 binds to the ECE-1b promoter specifically, as demonstrated by EMSA. The -338A allele of the ECE-1b promoter shows increased affinity for E2F-2 compared to the -338C allele, and is associated with increased promoter activity in reporter assays.","method":"EMSA (electrophoretic mobility shift assay), transient transfection reporter assay","journal":"Human molecular genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct DNA binding by EMSA plus functional reporter assay, single lab","pmids":["12566389"],"is_preprint":false},{"year":2003,"finding":"Drosophila RBF1 forms complexes with both E2F1/DP and E2F2/DP that cooperate to repress pre-replication complex (pre-RC) gene expression in follicle cells, thereby confining DNA synthesis to gene amplification sites. Reducing Orc2, Orc5, or Mcm2 gene dose by half suppresses the ectopic genomic replication phenotype of E2f2 mutants (genetic epistasis). E2F1 and E2F2 repressors function redundantly for some genes in the embryo but have context-dependent relative contributions.","method":"Drosophila genetics (epistasis by dosage reduction), RT-PCR, DNA microarray analysis of pre-RC gene transcripts","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — genetic epistasis with dosage reduction combined with transcriptome analysis; Drosophila ortholog with replicated findings","pmids":["12612083"],"is_preprint":false},{"year":2003,"finding":"E2F2 transgenic mice (driven by Emu/pim1 promoter targeting thymic epithelial cells) develop cortical thymomas from 20 weeks, demonstrating that E2F2 deregulation promotes cell division and oncogenic transformation of thymic epithelial cells. In contrast, E2F1 transgenic mice do not develop cortical thymomas under the same promoter, indicating functional specificity.","method":"Transgenic mouse generation, tumor monitoring, immunohistochemistry (cytokeratin, ER-TR4), thymocyte subset analysis","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — transgenic mouse model with defined tumor phenotype and histological characterization, single lab","pmids":["14684733"],"is_preprint":false},{"year":2003,"finding":"Loss of both E2F1 and E2F2 in pancreatic cells leads to increased rates of DNA replication, apoptosis, and severe pancreatic atrophy. DNA replication and cell cycle control genes are upregulated in E2F1/E2F2 compound-mutant pancreas, indicating these genes are normally repressed by E2F1/E2F2 activity. E2F1/E2F2 activity is also required for maintenance of differentiated pancreatic phenotypes, as ductal and adipocyte marker genes were upregulated while pancreatic cell markers were downregulated.","method":"E2f1/E2f2 compound-mutant mice, gene expression profiling, histology, cell cycle analysis","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 / Strong — compound genetic knockouts with gene expression profiling and multiple tissue phenotypes; replicated independently from PMID:15146237","pmids":["14566047","15146237"],"is_preprint":false},{"year":2004,"finding":"The Drosophila Myb-MuvB complex contains E2F2, DP, RBF1, RBF2, LIN-52, L(3)MBT, and Rpd3 (HDAC), identified by affinity chromatography fractionation of embryo extracts. Members of this complex localize to promoters and co-repress transcription of developmentally regulated genes.","method":"Affinity chromatography of Drosophila embryo extracts, co-purification, chromatin immunoprecipitation, transcriptional repression assays","journal":"Genes & development","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — biochemical purification plus ChIP plus functional transcription repression assay; Drosophila ortholog, multiple orthogonal methods","pmids":["15545624"],"is_preprint":false},{"year":2005,"finding":"HPV31 E7 activates E2F2 transcription specifically in differentiating (suprabasal) keratinocytes by inhibiting HDAC binding to the E2F2 promoter, as demonstrated by chromatin immunoprecipitation. siRNA knockdown of E2F2 confirmed that E2F2 expression is required for HPV replication but not for cell proliferation in this context.","method":"Chromatin immunoprecipitation (ChIP), siRNA knockdown, HPV replication assays, differentiated keratinocyte model","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 2 / Strong — ChIP plus siRNA knockdown with direct functional readout (viral replication); multiple orthogonal methods, single lab","pmids":["15861133"],"is_preprint":false},{"year":2005,"finding":"Directed expression of E2F2 (but not E2F1, E2F3, or E2F5) in neonatal cardiomyocytes induces mitotic cell division without triggering apoptosis, while E2F1 and E2F3 induce both S-phase entry and apoptosis. E2F2 and E2F4 both induce S-phase entry, but only E2F2 results in actual mitotic division. E2F2/E2F4 expression down-regulate pro-apoptotic genes that are activated by E2F1/E2F3.","method":"Adenovirus-mediated gene transfer, BrdU incorporation, TUNEL apoptosis assay, quantitative RT-PCR of cell cycle and apoptotic genes","journal":"Circulation research","confidence":"High","confidence_rationale":"Tier 2 / Strong — comparative overexpression of multiple E2F family members with clear phenotypic specificity, multiple orthogonal readouts (BrdU, TUNEL, qRT-PCR)","pmids":["15718499"],"is_preprint":false},{"year":2005,"finding":"Overexpression of E2F2 in nonproliferating human corneal endothelial cells (ex vivo adenoviral delivery) induces G1-to-S phase progression and increased cell density without significant apoptosis, as shown by BrdU incorporation and specular microscopy.","method":"Adenoviral E2F2 overexpression in ex vivo human corneas, BrdU incorporation, specular microscopy, TUNEL assay","journal":"Investigative ophthalmology & visual science","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct overexpression with BrdU and cell counting readouts; single lab, one model system","pmids":["16186339"],"is_preprint":false},{"year":2006,"finding":"E2f1, E2f2, and E2f3 are required for oncogene-mediated transformation. Their combined inactivation elevates p21(CIP1) protein levels and causes cell cycle arrest at G1/S and G2/M. Loss of p21(CIP1) (but not p53) restores G1/S entry in triple-knockout cells. Loss of p53 (but not p21) allows cells to progress through both G1/S and mitosis and renders cells sensitive to transformation, indicating the critical function of E2F1-3 is in negative regulation of the p53-p21(CIP1) axis.","method":"Compound E2f conditional knockout MEFs, cell synchronization, p21/p53 inactivation by genetic crossing or dominant-negative, oncogene transformation assays","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — compound conditional knockouts combined with genetic epistasis (p21 and p53 inactivation) and transformation assays; multiple orthogonal methods","pmids":["17008321"],"is_preprint":false},{"year":2007,"finding":"E2F2 functions as a transcriptional repressor of cell cycle genes to establish G0 quiescence. Loss of E2F2 causes T cells and MEFs to enter S phase early and undergo accelerated cell division. A large set of E2F target genes (Mcm's, cyclins, Cdc2a) that are normally silent in G0 are actively expressed in quiescent E2F2-knockout cells. ChIP analysis shows E2F2 occupies promoters of these genes in G0, confirming direct repressive role. Classic E2F activators E2F1 and E2F3 are largely dispensable for this quiescence maintenance.","method":"E2f2 knockout mice, S phase entry assays (BrdU), ChIP, shRNA knockdown of E2F3, compound E2F1/E2F2 double-knockout","journal":"Cell cycle (Georgetown, Tex.)","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — genetic knockout combined with ChIP (direct promoter binding) and orthogonal shRNA knockdown; multiple labs confirming quiescence role","pmids":["19066456"],"is_preprint":false},{"year":2007,"finding":"Combined inactivation of E2f1, E2f2, and E2f3 in MEFs activates p53 and induces p21(CIP1), leading to inhibition of CDK activity and Rb phosphorylation, Rb/E2F-mediated target gene repression, and severe proliferative block. Inactivation of p53 in E2f1/2/3-deficient cells prevents p21 induction, restores CDK activity and Rb phosphorylation, and allows near-normal E2F target gene expression and response to growth signals.","method":"Conditional triple knockout MEFs, p53 conditional knockout, immunoblot for CDK activity and Rb phosphorylation, RT-PCR of E2F targets","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — conditional compound knockouts with genetic rescue (p53 deletion), multiple biochemical readouts","pmids":["17167174"],"is_preprint":false},{"year":2007,"finding":"Loss of E2f2 accelerates Myc-driven T cell lymphomagenesis in a bitransgenic mouse model, while loss of E2f1 or E2f3 has no significant effect. Loss of a single copy of E2f2 also accelerates tumorigenesis (haploinsufficiency). Myc-overexpressing T cells are more resistant to apoptosis in the absence of E2f2, and reintroduction of E2F2 into tumor cells increases apoptosis and inhibits tumorigenesis, identifying E2f2 as a tumor suppressor that modulates apoptosis.","method":"Bitransgenic mouse model (MMTV-Myc × E2f KO), tumor progression monitoring, apoptosis assays, E2F2 reintroduction into tumor cells","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 / Strong — in vivo bitransgenic genetic model with rescue experiment (E2F2 reintroduction), multiple readouts","pmids":["17881568"],"is_preprint":false},{"year":2007,"finding":"p53 and Rb (via E2Fs) repress survivin transcription in normal human melanocytes through direct promoter binding. E2F2 specifically binds a novel E2F site in the survivin promoter and negatively regulates survivin expression. Mutation of either the p53 or E2F binding sites is sufficient to increase survivin promoter activity.","method":"ChIP assay, promoter-reporter assays with site-directed mutation, siRNA knockdown of E2F2","journal":"Carcinogenesis","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP plus reporter assays with mutation, single lab","pmids":["17916908"],"is_preprint":false},{"year":2007,"finding":"E2f-2 is the major pRb-associated E2F in end-stage red cells (erythroblasts) and the predominant E2F detected at key target gene promoters during terminal erythroid differentiation. E2f-2 loss restores terminal erythroid maturation (including enucleation) to Rb-null red cells. Deletion of E2f-2 also extends the lifespan of Rb-null mice. Aberrant S-phase entry of Rb-null erythroblasts is inhibited by E2f-2 deletion.","method":"Compound Rb/E2f-2 knockout mice, ChIP at target gene promoters, cell cycle analysis, enucleation assays, survival analysis","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — compound knockout with ChIP and multiple phenotypic readouts (maturation, enucleation, lifespan); orthogonally confirmed","pmids":["17923680"],"is_preprint":false},{"year":2008,"finding":"EKLF/KLF1 directly occupies the proximal E2f2 promoter in erythroid progenitor cells in vivo. Loss of EKLF reduces E2f2 mRNA and protein levels in early erythroid progenitors, leading to a delay in G1-to-S phase transition. EKLF binding sites in the E2f2 promoter lie in a region of EKLF-dependent DNase I sensitivity.","method":"Eklf-knockout mice, ChIP (EKLF occupancy at E2f2 promoter), DNase I hypersensitivity, RT-PCR, western blot, cell cycle analysis","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — ChIP for direct occupancy combined with knockout phenotype and DNase I sensitivity; multiple orthogonal methods","pmids":["18852285"],"is_preprint":false},{"year":2008,"finding":"Directed expression of E2F2 in adult mouse hearts (via adenoviral vector) induces proliferation of cardiomyocytes in vivo, without increasing apoptosis. E2F2 in vivo causes strong induction of cyclin A and cyclin E while not affecting CDK inhibitor p21. E2F2 also down-regulates pro-apoptotic genes caspase-6 and apaf-1.","method":"Adenoviral E2F2 delivery in mice, histological section analysis, quantitative RT-PCR, western blot of cell cycle regulatory proteins","journal":"Cardiovascular research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo overexpression with histology and gene expression analysis; single lab replicating prior in vitro finding","pmids":["18628254"],"is_preprint":false},{"year":2009,"finding":"GATA-1 forms a tricomplex with pRb and E2F-2 during terminal erythroid differentiation. This interaction requires a LXCXE motif conserved in GATA-1 orthologs (absent from other GATA family members). The GATA-1/pRb/E2F-2 complex stalls cell proliferation and steers erythroid precursors toward terminal differentiation. FOG-1 can disrupt this complex by displacing pRb/E2F-2 from GATA-1. A GATA-1 mutant unable to bind pRb fails to inhibit proliferation and causes embryonic lethality by anemia.","method":"Co-immunoprecipitation, domain mapping (LXCXE motif), GATA-1 mutant mouse models, in vitro disruption assay with FOG-1, cell proliferation assays","journal":"PLoS biology","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — reciprocal Co-IP, domain mutant, in vivo rescue/lethality, in vitro disruption; multiple orthogonal methods in a single rigorous study","pmids":["19513100"],"is_preprint":false},{"year":2009,"finding":"EKLF/KLF1 directly activates E2f2 through a novel intronic enhancer containing conserved CACC, GATA, and E-BOX elements. EKLF occupies this E2f2 enhancer in vivo (ChIP). Loss of EKLF causes aberrant S-phase entry, and additional genetic depletion of Rb (epistasis) partially restores normal cell cycle dynamics, establishing a causal link between reduced E2f2 and the EKLF cell cycle defect.","method":"ChIP (EKLF occupancy at E2f2 intronic enhancer), Rb/EKLF double-knockout epistasis, cell cycle analysis","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — ChIP plus genetic epistasis; replicates and extends PMID:18852285 findings with enhancer identification","pmids":["19457859"],"is_preprint":false},{"year":2009,"finding":"E2F2 directly binds the ECE-1b promoter in endothelial cells (confirmed by ChIP) and activates ECE-1b transcription (confirmed by promoter-reporter assay). Loss of E2F2 leads to decreased ECE-1b mRNA, elevated membranous ECE-1 isoforms (ECE-1a, -1c, -1d), deregulated ECE-1 activity, increased vascular contractility, and higher blood pressure in E2F2-null mice. Sam68 co-immunoprecipitates with E2F2, occupies the ECE-1b promoter (ChIP), and represses E2F2-mediated ECE-1b transcription.","method":"ChIP (E2F2 and Sam68 at ECE-1b promoter), promoter-reporter assays, co-immunoprecipitation (Sam68-E2F2), tail-cuff blood pressure measurement in E2F2-null mice, ex vivo aortic ring contractility","journal":"Circulation","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — ChIP, co-IP, promoter-reporter, and in vivo physiological phenotype; multiple orthogonal methods","pmids":["19752322"],"is_preprint":false},{"year":2009,"finding":"miR-24 directly regulates E2F2 expression by binding seedless but highly complementary sequences in the E2F2 3'UTR. Enhanced proliferation from antagonizing miR-24 is abrogated by knocking down E2F2, and miR-24-insensitive E2F2 rescues miR-24-mediated inhibition of proliferation, demonstrating that E2F2 is a critical functional target of miR-24.","method":"miRNA overexpression/antagonism, E2F2 knockdown rescue experiment, miR-24-resistant E2F2 rescue, microarray-based target identification","journal":"Molecular cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple complementary experiments including rescue with miRNA-insensitive E2F2 and knockdown epistasis","pmids":["19748357"],"is_preprint":false},{"year":2010,"finding":"E2F1/E2F2 deficiency in differentiating bone marrow-derived macrophages results in accelerated DNA replication and cellular division, accompanied by early expression of DNA replication and cell cycle regulators. Rapid proliferation is followed by induction of a DNA damage response and p21(CIP1)-dependent senescence. Senescence is not triggered in the absence of DNA replication, establishing a causal link between E2F1/E2F2 loss, DNA hyper-replication, and senescence.","method":"Compound E2f1/E2f2 knockout bone marrow differentiation, BrdU incorporation, gene expression profiling, aphidicolin (replication inhibitor) experiment, p21 pathway analysis","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 2 / Strong — compound knockout with pharmacological intervention (aphidicolin) to establish causal link; multiple orthogonal methods","pmids":["20676136"],"is_preprint":false},{"year":2010,"finding":"Drosophila dE2F2 (E2F2), together with net E2F activity (assessed by dDp mutation), inhibits p53-independent IR-induced apoptosis in larval imaginal discs. dE2F1 promotes IR-induced p53-independent apoptosis and is required for transcriptional induction of the pro-apoptotic gene hid after irradiation when p53 is mutated. These two E2F homologs have opposing effects on p53-independent apoptosis.","method":"Drosophila genetics (E2f2 and Dp mutants), transcriptional reporters (hid), irradiation, p53 mutation background","journal":"Developmental biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic mutants with transcriptional reporter readout in Drosophila; Drosophila ortholog, single lab","pmids":["20659447"],"is_preprint":false},{"year":2011,"finding":"E2F2 is required for adult hepatocyte proliferation and timely liver regeneration after partial hepatectomy. E2F2-knockout hepatocytes exhibit a reduced rate of S-phase entry and delayed liver regeneration. Transcriptome analysis shows that genes for cell cycle, apoptosis, and wound-healing response are absent in posthepatectomized E2F2-/- mice.","method":"E2f2-knockout mice, partial hepatectomy model, BrdU incorporation, transcriptome analysis","journal":"American journal of physiology. Gastrointestinal and liver physiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — knockout mouse with defined phenotype (delayed regeneration, reduced S-phase) plus transcriptome analysis; single lab","pmids":["21527726"],"is_preprint":false},{"year":2013,"finding":"E2F2 occupies promoters of a large number of cell cycle and DNA metabolism genes during T cell quiescence (ChIP-chip genome-wide analysis). E2F2 and CREB cooperate in transcriptional repression of a subset of target genes (Mcm5, Chk1). CREB knockdown (siRNA), dominant-negative KCREB expression, or mutation of the CRE motif in the Mcm5 promoter relieves E2F2-mediated repression. This repression is retinoblastoma-independent.","method":"ChIP-chip (genome-wide), expression profiling, luciferase reporter assays, siRNA knockdown (CREB), dominant-negative CREB, CRE site mutation","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — ChIP-chip combined with multiple orthogonal functional assays (siRNA, dominant-negative, promoter mutation); single lab but highly rigorous","pmids":["24038359"],"is_preprint":false},{"year":2013,"finding":"Drosophila Myb-null cytokinesis failure (binucleate cells) is suppressed by loss of E2F2 or Mip130 (dREAM complex subunits), indicating that transcriptional repression by the dREAM complex requires E2F2 for its full activity. The Myb-null phenotype is sensitive to dosage of E2F2, Mip120, Caf1, and Lin-52. Reduction of histone variant H2Av/H2A.z also suppresses the Myb-null phenotype, implicating H2A.z in dREAM-mediated transcriptional repression.","method":"Drosophila genetics (Myb-null with E2F2/dREAM subunit mutations), quantitative phenotypic readout (binucleate cell frequency), H2Av dosage reduction","journal":"Molecular and cellular biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis in Drosophila with clear quantitative readout; Drosophila ortholog, single lab","pmids":["23438598"],"is_preprint":false},{"year":2013,"finding":"E2f2 (but not E2f1 or E2f3) is required and sufficient for cone photoreceptor apoptosis in Rb/p107 double-null retinas, demonstrating a direct, E2f1-independent apoptotic function. E2f2-induced cone death is p53-dependent (in contrast to E2f1-dependent apoptosis in other neurons which is p53-independent). E2f2 deletion rescues cone survival in Rb/p107-null retinas.","method":"Compound Rb/p107/E2f knockout mice, TUNEL apoptosis assay, genetic rescue experiments","journal":"Cell death and differentiation","confidence":"High","confidence_rationale":"Tier 2 / Strong — compound genetic knockouts with clear rescue; multiple E2f family members tested to establish specificity","pmids":["23558950"],"is_preprint":false},{"year":2013,"finding":"ALY (THO complex 4) associates with DNA-bound E2F2 and represses its transcriptional activity. ALY influences the expression of over 400 genes, including 98 genes with consensus E2F motifs, as determined by expression microarrays in ALY-overexpressing or ALY-silenced HEK293T cells expressing E2F2.","method":"Co-immunoprecipitation (ALY-E2F2 interaction), expression microarrays (ALY overexpression and siRNA silencing in E2F2-expressing cells)","journal":"Molecular & cellular proteomics : MCP","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP plus microarray functional readout; single lab","pmids":["23297349"],"is_preprint":false},{"year":2015,"finding":"Loss of E2F1 and E2F2 together (but not individually) prevents replicative stress in the pancreas. Combined inactivation leads to unscheduled DNA replication, DNA damage response activation, and p53-mediated mitochondrial apoptosis causing pancreatic atrophy and diabetes. Suppression of DNA replication in vivo with aphidicolin significantly inhibits the p53 pathway in double-knockout pancreas. Targeted p53 inactivation abrogates cellular apoptosis and prevents organ involution, establishing a causal E2F-p53 regulatory axis.","method":"E2f1/E2f2 double-knockout mice, aphidicolin treatment (in vivo replication suppression), p53 triple-knockout mice, DNA damage marker analysis, apoptosis assays","journal":"Cell death and differentiation","confidence":"High","confidence_rationale":"Tier 2 / Strong — compound knockout with pharmacological intervention plus genetic epistasis (p53 deletion); multiple orthogonal approaches","pmids":["25656653"],"is_preprint":false},{"year":2015,"finding":"E2F1 and E2F2 are transcriptionally induced in neuronal cells after DNA damage (genotoxic treatment), leading to increased protein levels via de novo synthesis. E2F1/E2F2 accumulate at sites of oxidative and UV-induced DNA damage and interact with γH2AX. E2F2 promotes Rad51 foci formation, interacts with GCN5 acetyltransferase, and induces histone acetylation following genotoxic insult. Ablation of E2F1 and E2F2 leads to DNA lesion accumulation, increased apoptosis, and reduced DNA repair capacity.","method":"Genotoxic treatment, de novo protein synthesis assays, co-immunoprecipitation (E2F2-γH2AX and E2F2-GCN5), immunofluorescence (E2F2 accumulation at damage sites, Rad51 foci), siRNA knockdown, cell viability assays","journal":"Cell cycle (Georgetown, Tex.)","confidence":"High","confidence_rationale":"Tier 2 / Strong — Co-IP with damage-response factors, immunofluorescence localization at damage sites, functional ablation; multiple orthogonal methods","pmids":["25892555"],"is_preprint":false},{"year":2016,"finding":"E2F-2 is required for efficient erythroblast enucleation and nuclear condensation during terminal erythroid differentiation. Citron Rho-interacting kinase (CRIK) is induced in erythroblasts in an E2F-2-dependent manner, and CRIK activity promotes efficient erythroblast enucleation and nuclear condensation. E2F-2 deletion impairs nuclear condensation in mature erythroblasts.","method":"E2f-2 knockout mice, enucleation assays, transcriptome profiling of E2F-2-null erythroblasts, functional inhibition/activation of CRIK","journal":"Molecular and cellular biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — knockout mice with transcriptome profiling and functional CRIK assays; single lab","pmids":["27795297"],"is_preprint":false},{"year":2016,"finding":"BRD4 inhibition (by JQ1) identifies E2F2 as a direct downstream target of BRD4 in liver cancer cells, confirmed by ChIP assay. Loss-of-function of E2F2 in liver cancer cells recapitulates BRD4 inhibition effects on cell cycle arrest.","method":"ChIP assay (BRD4 at E2F2 promoter), siRNA knockdown of E2F2, JQ1 treatment with gene expression analysis","journal":"Oncotarget","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP plus functional loss-of-function; single lab","pmids":["27081696"],"is_preprint":false},{"year":2018,"finding":"E2F2 directly binds the promoters of STAT1 and MyD88 (confirmed by ChIP and luciferase assays) and upregulates their expression, facilitating formation of STAT1/MyD88 complexes and AKT activation. This E2F2-STAT1/MyD88-AKT axis drives inflammatory cytokine (IL-1α, IL-1β, TNF-α) production in rheumatoid arthritis synovial fibroblasts. Silencing STAT1/MyD88 or inactivating AKT attenuates cytokine induction by E2F2.","method":"ChIP-PCR, luciferase reporter assay, co-immunoprecipitation (STAT1-MyD88 complex), western blot, E2f2-knockout mouse collagen arthritis model, siRNA knockdown","journal":"Arthritis research & therapy","confidence":"High","confidence_rationale":"Tier 2 / Strong — ChIP, Co-IP, reporter assay, in vivo knockout model, and epistasis by silencing downstream effectors; multiple orthogonal methods","pmids":["30286793"],"is_preprint":false},{"year":2021,"finding":"E2F2 directly binds the CPT2 promoter (confirmed by ChIP) and represses its transcription, inhibiting fatty acid oxidation. E2f2-knockout mice show enhanced fatty acid oxidation and increased CPT2 expression. E2f2 knockdown in liver recapitulates this, while E2f2 overexpression has opposing effects. This E2F2-CPT2 axis creates a lipid-rich environment promoting hepatocarcinogenesis.","method":"ChIP (E2F2 at CPT2 promoter), E2f2-knockout mice, shRNA knockdown in liver, E2f2 overexpression, fatty acid oxidation assays, DEN/HFD hepatocarcinogenesis model","journal":"Cancer research","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — ChIP for direct promoter binding combined with knockout, knockdown, overexpression and in vivo metabolic assays; multiple orthogonal methods","pmids":["33771899"],"is_preprint":false},{"year":2021,"finding":"E2F2 transcriptionally activates PFKFB4 by directly binding its promoter (confirmed by ChIP and luciferase assay), activating the PI3K/AKT signaling pathway to promote glioma cell glycolysis and malignant progression. PFKFB4 knockdown mitigates E2F2-driven glioma metastasis and glycolysis.","method":"ChIP, luciferase assay, PFKFB4 knockdown, E2F2 overexpression/knockdown, glycolysis assays, in vivo tumor growth/metastasis models","journal":"Life sciences","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP plus reporter assay plus functional epistasis; single lab","pmids":["33774025"],"is_preprint":false},{"year":2021,"finding":"B-Myb directly transactivates E2F2, and E2F2 in turn directly transactivates B-Myb, forming a reciprocal feed-forward transcriptional loop in colorectal cancer. B-Myb and E2F2 physically interact and co-occupy each other's promoters. Both B-Myb and E2F2 are required for ERK and AKT signaling pathway activation in colorectal cancer cells.","method":"Co-immunoprecipitation (B-Myb/E2F2 interaction), ChIP (B-Myb and E2F2 at each other's promoters), luciferase reporter assay, siRNA knockdown, in vivo orthotopic tumor model","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP, reciprocal ChIP, reporter assay, knockdown; multiple orthogonal methods","pmids":["34316028"],"is_preprint":false},{"year":2022,"finding":"E2F2 undergoes ubiquitination and proteasomal degradation via the atypical E3 ligase ZFP91. The natural product bufalin promotes E2F2-ZFP91 complex formation (identified by human proteome microarray and Co-IP/SILAC quantitative proteomics), leading to E2F2 polyubiquitination via K48-linked ubiquitin chains and degradation. E2F2 degradation causes transcriptional suppression of oncogenes including c-Myc, CCNE1, CCNE2, MCM5 and CDK1.","method":"Human proteome microarray, Co-IP with SILAC-based quantitative proteomics, ubiquitination assay (K48-linkage), proteasome inhibitor experiments, gene expression analysis","journal":"EBioMedicine","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — proteome microarray plus Co-IP/quantitative proteomics plus ubiquitination chain analysis; multiple orthogonal methods identifying E3 ligase and mechanism","pmids":["36375317"],"is_preprint":false},{"year":2010,"finding":"Loss of E2F2 in E2F2-deficient T lymphocytes leads to deregulated Aryl-hydrocarbon-receptor (Ahr) pathway. Proliferating E2F2-/- T cells express significantly higher levels of Aip, Ahr, and Arnt. E2F2 directly regulates the Aip gene promoter (binding confirmed), and E2F2-/- T cells show increased sensitivity to TCDD-triggered apoptosis. ChIP showed E2F2 binding to Ahr and Arnt promoters as well.","method":"Differential proteomics (E2F2-/- vs WT T cells), ChIP (E2F2 at Aip/Ahr/Arnt promoters), TCDD treatment apoptosis assay","journal":"Molecular & cellular proteomics : MCP","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — proteomics plus ChIP plus functional apoptosis assay; single lab","pmids":["20573986"],"is_preprint":false},{"year":2022,"finding":"E2F2 forms part of a core transcription regulatory circuitry with B-Myb and FOXM1 in lung adenocarcinoma; these three factors positively correlate in expression, physically associate, mutually transactivate each other, and regulate similar downstream gene cascades. E2F2 promotes LUAD growth in orthotopic mouse models.","method":"Co-immunoprecipitation (E2F2/B-Myb/FOXM1 interaction), ChIP, luciferase reporter assay, siRNA knockdown, orthotopic mouse tumor model","journal":"International journal of biological sciences","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP, ChIP, and reporter assays confirming physical and functional interaction; single lab","pmids":["35844795"],"is_preprint":false}],"current_model":"E2F2 is a transcription factor that functions primarily as a transcriptional repressor of cell cycle genes (including Mcm's, cyclins, and Cdc2a) to establish and maintain cellular quiescence (G0), forms a stable tricomplex with pRb and GATA-1 during erythroid differentiation, represses pre-replication complex gene expression in a conserved Myb-MuvB/dREAM complex, directly binds and represses the CPT2 promoter to regulate fatty acid oxidation, activates ECE-1b transcription in endothelial cells (regulated by Sam68 co-repressor) to control blood pressure, and is degraded via K48-linked ubiquitination by the atypical E3 ligase ZFP91; its loss in vivo leads to enhanced lymphocyte proliferation and autoimmunity, accelerated Myc-driven tumorigenesis, defective erythroid enucleation, and replicative stress-driven p53-dependent apoptosis, while its overexpression uniquely drives cardiomyocyte mitotic division without apoptosis."},"narrative":{"mechanistic_narrative":"E2F2 is a sequence-specific transcription factor of the E2F family that binds DNA as a heterodimer and contains conserved DNA-binding and retinoblastoma (Rb)-binding domains [PMID:8246995], functioning predominantly as a transcriptional repressor that establishes and maintains cellular quiescence (G0) by occupying and silencing cell-cycle and DNA-metabolism gene promoters (Mcm's, cyclins, Cdc2a) in resting cells [PMID:19066456, PMID:24038359]. In vivo, this repressive activity enforces immunologic self-tolerance and proliferative restraint: loss of E2F2 lowers the lymphocyte activation threshold and produces autoimmunity, and combined loss with E2F1 drives accelerated, unscheduled DNA replication that triggers a DNA-damage response and p53/p21-dependent apoptosis or senescence [PMID:11754817, PMID:20676136, PMID:25656653]. E2F2-mediated repression operates through conserved corepressor machinery — within the Drosophila Myb-MuvB/dREAM complex containing DP, RBF1/RBF2, LIN-52, L(3)MBT and Rpd3/HDAC [PMID:15545624, PMID:23438598], and in cooperation with partners such as CREB at human cell-cycle promoters in an Rb-independent manner [PMID:24038359]. Beyond cell-cycle control, E2F2 acts as a context-specific transcriptional activator, directly binding and inducing the ECE-1b promoter in endothelial cells (with Sam68 as a corepressor) to regulate vascular tone and blood pressure [PMID:19752322], and repressing the CPT2 promoter to limit fatty acid oxidation [PMID:33771899]. During terminal erythroid differentiation, E2F2 is the predominant pRb-associated E2F and assembles a pRb/E2F2/GATA-1 tricomplex that halts proliferation and promotes maturation and enucleation [PMID:17923680, PMID:19513100, PMID:27795297]. E2F2 is itself a node of regulation — transcriptionally controlled by Myc-responsive and E2F sites in its promoter [PMID:9271400] and by EKLF/KLF1 in erythroid cells [PMID:18852285, PMID:19457859], post-transcriptionally targeted by miR-24 [PMID:19748357], and degraded via K48-linked polyubiquitination by the atypical E3 ligase ZFP91 [PMID:36375317]. Functionally, E2F2 behaves as a tumor suppressor whose loss accelerates Myc-driven lymphomagenesis and modulates apoptosis [PMID:17881568], yet acts oncogenically in other contexts by driving glycolytic and proliferative programs [PMID:33774025, PMID:34316028].","teleology":[{"year":1993,"claim":"Established E2F2 as a distinct E2F-family transcription factor, defining its DNA-binding and Rb-binding domains and its requirement to function as a DNA-binding heterodimer.","evidence":"cDNA cloning, in vitro DNA-binding and complementation assays with HeLa E2F components, antibody cross-reactivity","pmids":["8246995"],"confidence":"High","gaps":["Did not define endogenous target genes or in vivo function","Heterodimer partner (DP) not directly mapped here"]},{"year":1997,"claim":"Clarified how E2F2 expression is itself controlled, showing its promoter integrates Myc-responsive activating E-boxes and repressive E2F sites for growth-dependent regulation.","evidence":"Promoter-reporter assays with deletion/mutation under growth stimulation","pmids":["9271400"],"confidence":"Medium","gaps":["Reporter-based, not endogenous chromatin context","Identity of repressive E2F at its own promoter unresolved"]},{"year":2001,"claim":"Defined the in vivo physiological role of E2F2 as a repressor enforcing immune self-tolerance and proliferative restraint, reframing it from an activator to a repressor.","evidence":"E2f2-knockout and E2f1/E2f2 double-knockout mice, T-cell proliferation/tolerance assays, tumor monitoring; Drosophila E2f2 loss-of-function with replication assays","pmids":["11754817","11713289","11748144"],"confidence":"High","gaps":["Direct promoter occupancy not yet shown in mammalian cells","Corepressor complexes mediating repression not identified"]},{"year":2002,"claim":"Demonstrated functional specificity among E2Fs in vivo, with E2F2 selectively contributing to Rb-loss-driven ectopic replication in defined tissues but not uniformly to apoptosis or ARF induction.","evidence":"Compound Rb/E2f knockout mice with BrdU/TUNEL; E2f1/2 knockout MEFs with oncogenic Ras/E1A and ARF assays; ARF promoter reporter analysis","pmids":["12065245","11883935","12082524"],"confidence":"High","gaps":["Mechanistic basis of E2F2 tissue specificity unresolved","Mixed activator/repressor behavior at ARF not reconciled"]},{"year":2003,"claim":"Showed E2F2 represses pre-replication-complex genes through a conserved RBF-containing repressor mechanism and that E2F2 deregulation can transform cells, while also acting as a sequence-specific activator at ECE-1b.","evidence":"Drosophila genetic epistasis with pre-RC dosage and microarray; E2F2 transgenic mice developing thymomas; compound mutant pancreas profiling; EMSA/reporter at ECE-1b promoter","pmids":["12612083","14684733","14566047","15146237","12566389"],"confidence":"High","gaps":["Full subunit composition of the repressor complex not yet defined","Activator versus repressor switch determinants unknown"]},{"year":2004,"claim":"Identified the molecular machinery for E2F2 repression by purifying the Myb-MuvB/dREAM complex containing E2F2, DP, RBF1/RBF2, LIN-52, L(3)MBT, and the HDAC Rpd3.","evidence":"Affinity chromatography of Drosophila embryo extracts, ChIP, transcriptional repression assays","pmids":["15545624"],"confidence":"High","gaps":["Human ortholog complex composition not directly demonstrated here","Recruitment hierarchy of subunits to promoters not resolved"]},{"year":2005,"claim":"Revealed unique E2F2 cell-fate outputs — viral exploitation of E2F2 induction for replication and an apoptosis-free proliferative program in cardiomyocytes that distinguishes it from E2F1/E2F3.","evidence":"ChIP and siRNA in differentiating keratinocytes with HPV replication assays; comparative adenoviral E2F overexpression in cardiomyocytes and corneal endothelium with BrdU/TUNEL/qRT-PCR","pmids":["15861133","15718499","16186339"],"confidence":"High","gaps":["Molecular basis for E2F2 suppressing apoptosis while inducing division not fully defined","Target genes distinguishing E2F2 from E2F1 incompletely mapped"]},{"year":2007,"claim":"Defined E2F2 as a direct repressor maintaining quiescence by occupying cell-cycle gene promoters, and established that combined E2F1-3 loss enforces arrest through the p53-p21 axis.","evidence":"E2f2 knockout mice with ChIP and BrdU; conditional triple-knockout MEFs with p53/p21 genetic epistasis and CDK/Rb biochemistry; bitransgenic Myc model with E2F2 reintroduction; survivin promoter ChIP/reporter","pmids":["19066456","17008321","17167174","17881568","17916908"],"confidence":"High","gaps":["Corepressors at quiescence promoters not all identified","Relationship between repressive and pro-apoptotic functions unresolved"]},{"year":2008,"claim":"Connected E2F2 to erythroid cell-cycle control upstream and downstream — as an EKLF/KLF1 transcriptional target driving G1/S progression and as an in vivo cardiomyocyte proliferation inducer that downregulates pro-apoptotic genes.","evidence":"Eklf-knockout mice with ChIP and DNase I hypersensitivity; adenoviral E2F2 delivery in adult mouse hearts with histology and qRT-PCR","pmids":["18852285","18628254"],"confidence":"High","gaps":["Whether EKLF-E2F2 axis generalizes beyond erythroid lineage unknown","Mechanism of pro-apoptotic gene downregulation by E2F2 not defined"]},{"year":2009,"claim":"Resolved the erythroid pRb/E2F2/GATA-1 tricomplex and an EKLF intronic enhancer driving E2F2, and defined E2F2 as a direct ECE-1b activator controlling blood pressure with Sam68 as corepressor and miR-24 as a post-transcriptional regulator.","evidence":"Co-IP and LXCXE domain mapping with GATA-1 mutant mice; ChIP and Rb/EKLF epistasis at E2f2 enhancer; ChIP/co-IP/reporter and in vivo blood pressure in E2F2-null mice; miR-24 3'UTR rescue experiments","pmids":["19513100","19457859","19752322","19748357"],"confidence":"High","gaps":["How the same factor switches between repression and activation at different promoters unresolved","Sam68 mechanism of corepression not structurally defined"]},{"year":2010,"claim":"Established a causal chain from E2F1/E2F2 loss through DNA hyper-replication to senescence, and extended E2F2 targets to the Ahr xenobiotic pathway and p53-independent apoptosis regulation.","evidence":"Compound knockout bone-marrow differentiation with aphidicolin; differential proteomics and ChIP at Aip/Ahr/Arnt with TCDD apoptosis; Drosophila E2f2/Dp genetics on IR-induced apoptosis","pmids":["20676136","20573986","20659447"],"confidence":"High","gaps":["Direct versus indirect contribution of E2F2 to senescence not separated from E2F1","Ahr regulation in other cell types untested"]},{"year":2013,"claim":"Identified E2F2's combinatorial repression partners (CREB) genome-wide and an unexpected role in the DNA-damage response, with E2F2 localizing to lesions, interacting with γH2AX and GCN5, and promoting Rad51 foci and repair.","evidence":"ChIP-chip with CREB siRNA/dominant-negative and promoter mutation; compound Rb/p107/E2f knockout retinas with TUNEL rescue; co-IP and immunofluorescence at damage sites; ALY co-IP and microarray; Drosophila dREAM/Myb epistasis","pmids":["24038359","23558950","25892555","23297349","23438598"],"confidence":"High","gaps":["Whether DNA-repair role is transcriptional or direct chromatin function not resolved","Stoichiometry of E2F2 with CREB/ALY corepressors unknown"]},{"year":2015,"claim":"Cemented the E2F-p53 axis in vivo, showing pancreatic involution from E2F1/E2F2 loss arises causally from replicative stress driving p53-mediated mitochondrial apoptosis.","evidence":"E2f1/E2f2 double-knockout mice with in vivo aphidicolin and p53 genetic inactivation, DNA-damage and apoptosis assays","pmids":["25656653"],"confidence":"High","gaps":["Tissue-selectivity of the replicative-stress phenotype unexplained","E2F2-specific versus shared E2F1 contribution not separated"]},{"year":2016,"claim":"Linked E2F2 mechanistically to erythroblast enucleation via CRIK induction and identified E2F2 as a direct BRD4 transcriptional target in liver cancer.","evidence":"E2f-2 knockout erythroblast enucleation assays with transcriptome and CRIK functional manipulation; BRD4/JQ1 ChIP and E2F2 loss-of-function in liver cancer cells","pmids":["27795297","27081696"],"confidence":"Medium","gaps":["Direct E2F2 occupancy at CRIK not shown","BRD4-E2F2 axis tested in a single cancer context"]},{"year":2018,"claim":"Revealed an activating, pro-inflammatory E2F2 program in rheumatoid arthritis, directly inducing STAT1 and MyD88 to drive an AKT-dependent cytokine cascade.","evidence":"ChIP-PCR, luciferase, co-IP of STAT1/MyD88, E2f2-knockout collagen arthritis model, downstream effector silencing","pmids":["30286793"],"confidence":"High","gaps":["How E2F2 switches to an activator at inflammatory promoters not defined","Generalizability beyond synovial fibroblasts untested"]},{"year":2021,"claim":"Expanded E2F2's direct target repertoire into metabolism and oncogenic signaling — repressing CPT2 to suppress fatty acid oxidation, activating PFKFB4 to drive glycolysis, and forming a reciprocal feed-forward loop with B-Myb.","evidence":"ChIP with knockout/knockdown/overexpression and in vivo metabolic and tumor models for CPT2; ChIP/reporter/knockdown for PFKFB4 glycolysis; reciprocal co-IP/ChIP for B-Myb loop","pmids":["33771899","33774025","34316028"],"confidence":"High","gaps":["Determinants of E2F2 repressor-versus-activator behavior at metabolic genes unresolved","Direct partners stabilizing E2F2 on these promoters not mapped"]},{"year":2022,"claim":"Defined E2F2 degradation by the atypical E3 ligase ZFP91 via K48-linked ubiquitination and placed E2F2 within a B-Myb/FOXM1 core transcriptional circuit in cancer.","evidence":"Proteome microarray, co-IP/SILAC proteomics, K48-ubiquitination assays, bufalin treatment; co-IP/ChIP/reporter and orthotopic models for the B-Myb/FOXM1 circuit","pmids":["36375317","35844795"],"confidence":"High","gaps":["Physiological signals controlling ZFP91-E2F2 degradation beyond bufalin unknown","Structural basis of ZFP91 substrate recognition not defined"]},{"year":null,"claim":"It remains unresolved what molecular determinants switch E2F2 between transcriptional repressor (cell-cycle, CPT2) and activator (ECE-1b, STAT1/MyD88, PFKFB4) on different promoters, and how corepressor versus coactivator recruitment is selected in a given cell context.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unifying mechanism distinguishing activator from repressor promoters","Cell-type-specific cofactor determinants undefined","Structural basis of context-dependent partner selection unknown"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140110","term_label":"transcription regulator activity","supporting_discovery_ids":[0,18,27,32,40,41]},{"term_id":"GO:0003677","term_label":"DNA binding","supporting_discovery_ids":[0,9,27,41]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[13,18,32,37]}],"pathway":[{"term_id":"R-HSA-1640170","term_label":"Cell Cycle","supporting_discovery_ids":[18,19,36]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[0,18,27,41]},{"term_id":"R-HSA-73894","term_label":"DNA Repair","supporting_discovery_ids":[37]},{"term_id":"R-HSA-5357801","term_label":"Programmed Cell Death","supporting_discovery_ids":[20,34,36]}],"complexes":["Myb-MuvB/dREAM complex","pRb/E2F2/GATA-1 tricomplex"],"partners":["RB1","GATA1","CREB","SAM68 (KHDRBS1)","ZFP91","B-MYB (MYBL2)","FOXM1","GCN5 (KAT2A)"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q14209","full_name":"Transcription factor E2F2","aliases":[],"length_aa":437,"mass_kda":47.5,"function":"Transcription activator that binds DNA cooperatively with DP proteins through the E2 recognition site, 5'-TTTC[CG]CGC-3' found in the promoter region of a number of genes whose products are involved in cell cycle regulation or in DNA replication. The DRTF1/E2F complex functions in the control of cell-cycle progression from g1 to s phase. E2F2 binds specifically to RB1 in a cell-cycle dependent manner","subcellular_location":"Nucleus","url":"https://www.uniprot.org/uniprotkb/Q14209/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/E2F2","classification":"Not Classified","n_dependent_lines":4,"n_total_lines":1208,"dependency_fraction":0.0033112582781456954},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/E2F2","total_profiled":1310},"omim":[{"mim_id":"615576","title":"MICRO RNA 185; MIR185","url":"https://www.omim.org/entry/615576"},{"mim_id":"612270","title":"CELL DIVISION CYCLE-ASSOCIATED PROTEIN 4; CDCA4","url":"https://www.omim.org/entry/612270"},{"mim_id":"609486","title":"E2F-ASSOCIATED PHOSPHOPROTEIN; EAPP","url":"https://www.omim.org/entry/609486"},{"mim_id":"607305","title":"MDS2 GENE","url":"https://www.omim.org/entry/607305"},{"mim_id":"601990","title":"TUMOR PROTEIN p73; TP73","url":"https://www.omim.org/entry/601990"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Group enriched","tissue_distribution":"Detected in some","driving_tissues":[{"tissue":"bone marrow","ntpm":23.7},{"tissue":"esophagus","ntpm":8.3},{"tissue":"lymphoid tissue","ntpm":14.7}],"url":"https://www.proteinatlas.org/search/E2F2"},"hgnc":{"alias_symbol":["E2F-2"],"prev_symbol":[]},"alphafold":{"accession":"Q14209","domains":[{"cath_id":"1.10.10.10","chopping":"132-193","consensus_level":"high","plddt":91.4685,"start":132,"end":193},{"cath_id":"-","chopping":"250-282_290-304","consensus_level":"medium","plddt":91.8892,"start":250,"end":304},{"cath_id":"1.20.5","chopping":"202-249","consensus_level":"medium","plddt":91.8531,"start":202,"end":249}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q14209","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q14209-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q14209-F1-predicted_aligned_error_v6.png","plddt_mean":63.12},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=E2F2","jax_strain_url":"https://www.jax.org/strain/search?query=E2F2"},"sequence":{"accession":"Q14209","fasta_url":"https://rest.uniprot.org/uniprotkb/Q14209.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q14209/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q14209"}},"corpus_meta":[{"pmid":"19748357","id":"PMC_19748357","title":"miR-24 Inhibits cell proliferation by targeting E2F2, MYC, and other cell-cycle genes via binding to \"seedless\" 3'UTR microRNA recognition elements.","date":"2009","source":"Molecular cell","url":"https://pubmed.ncbi.nlm.nih.gov/19748357","citation_count":498,"is_preprint":false},{"pmid":"33221435","id":"PMC_33221435","title":"M2 Macrophage-Derived Exosomes Promote Angiogenesis and Growth of Pancreatic Ductal Adenocarcinoma by Targeting E2F2.","date":"2020","source":"Molecular therapy : the journal of the American Society of Gene Therapy","url":"https://pubmed.ncbi.nlm.nih.gov/33221435","citation_count":250,"is_preprint":false},{"pmid":"15545624","id":"PMC_15545624","title":"Identification of a Drosophila Myb-E2F2/RBF transcriptional repressor complex.","date":"2004","source":"Genes & development","url":"https://pubmed.ncbi.nlm.nih.gov/15545624","citation_count":229,"is_preprint":false},{"pmid":"20418948","id":"PMC_20418948","title":"MicroRNA let-7a inhibits proliferation of human prostate cancer cells in vitro and in vivo by targeting E2F2 and CCND2.","date":"2010","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/20418948","citation_count":200,"is_preprint":false},{"pmid":"8246995","id":"PMC_8246995","title":"Cloning and characterization of E2F-2, a novel protein with the biochemical properties of transcription factor E2F.","date":"1993","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/8246995","citation_count":191,"is_preprint":false},{"pmid":"9271400","id":"PMC_9271400","title":"Identification of positively and negatively acting elements regulating expression of the E2F2 gene in response to cell growth signals.","date":"1997","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/9271400","citation_count":185,"is_preprint":false},{"pmid":"11754817","id":"PMC_11754817","title":"Mutation of E2F2 in mice causes enhanced T lymphocyte proliferation, leading to the development of autoimmunity.","date":"2001","source":"Immunity","url":"https://pubmed.ncbi.nlm.nih.gov/11754817","citation_count":127,"is_preprint":false},{"pmid":"30537738","id":"PMC_30537738","title":"Circular RNA circPVT1 Promotes Proliferation and Invasion Through Sponging miR-125b and Activating E2F2 Signaling in Non-Small Cell Lung Cancer.","date":"2018","source":"Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry, and pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/30537738","citation_count":108,"is_preprint":false},{"pmid":"17916908","id":"PMC_17916908","title":"Survivin repression by p53, Rb and E2F2 in normal human melanocytes.","date":"2007","source":"Carcinogenesis","url":"https://pubmed.ncbi.nlm.nih.gov/17916908","citation_count":95,"is_preprint":false},{"pmid":"11713289","id":"PMC_11713289","title":"E2F1 and E2F2 determine thresholds for antigen-induced T-cell proliferation and suppress 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proteomics analysis reveals a role for E2F2 in the regulation of the Ahr pathway in T lymphocytes.","date":"2010","source":"Molecular & cellular proteomics : MCP","url":"https://pubmed.ncbi.nlm.nih.gov/20573986","citation_count":17,"is_preprint":false},{"pmid":"36140689","id":"PMC_36140689","title":"Alteration of E2F2 Expression in Governing Endothelial Cell Senescence.","date":"2022","source":"Genes","url":"https://pubmed.ncbi.nlm.nih.gov/36140689","citation_count":16,"is_preprint":false},{"pmid":"30655803","id":"PMC_30655803","title":"miR-218 suppresses the proliferation of osteosarcoma through downregulation of E2F2.","date":"2018","source":"Oncology letters","url":"https://pubmed.ncbi.nlm.nih.gov/30655803","citation_count":16,"is_preprint":false},{"pmid":"31467515","id":"PMC_31467515","title":"PPAR-γ Ligand Inhibits Nasopharyngeal Carcinoma Cell Proliferation and Metastasis by Regulating E2F2.","date":"2019","source":"PPAR research","url":"https://pubmed.ncbi.nlm.nih.gov/31467515","citation_count":15,"is_preprint":false},{"pmid":"23297349","id":"PMC_23297349","title":"The nuclear protein ALY binds to and modulates the activity of transcription factor E2F2.","date":"2013","source":"Molecular & cellular proteomics : MCP","url":"https://pubmed.ncbi.nlm.nih.gov/23297349","citation_count":15,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":50439,"output_tokens":12783,"usd":0.171531,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":24142,"output_tokens":6231,"usd":0.138242,"stage2_stop_reason":"end_turn"},"total_usd":0.309773,"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\": 1993,\n      \"finding\": \"E2F2 (E2F-2) was cloned and found to share 46% amino acid identity with E2F1. The DNA binding domain and retinoblastoma (Rb) protein binding domain functions are conserved. E2F2 DNA binding activity is dramatically enhanced by complementation with HeLa cell E2F components, consistent with E2F binding DNA as a heterodimer, and anti-E2F-2 antibodies cross-react with purified HeLa cell E2F.\",\n      \"method\": \"cDNA cloning, DNA binding assays, antibody cross-reactivity, complementation assays with SDS-PAGE-purified HeLa cell E2F components\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro DNA binding assays, domain functional validation, and biochemical complementation; foundational characterization paper\",\n      \"pmids\": [\"8246995\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1997,\n      \"finding\": \"The E2F2 promoter contains E-box elements that function as Myc-responsive activation sites and E2F binding sites that mediate negative (repressive) regulation in quiescent cells. Both elements contribute to the cell-growth-dependent control of E2F2 expression, similar to regulation of the E2F1 gene promoter.\",\n      \"method\": \"Promoter reporter assays, deletion/mutation analysis, growth stimulation experiments\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — promoter-reporter assays with deletion mutants in multiple conditions, single lab\",\n      \"pmids\": [\"9271400\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"E2F2 is required for immunologic self-tolerance. E2F2-deficient T lymphocytes exhibit enhanced TCR-stimulated proliferation and a lower activation threshold. Rather than functioning as a transcriptional activator, E2F2 appears to function as a transcriptional repressor of genes required for S phase entry, particularly E2F1.\",\n      \"method\": \"E2f2 knockout mice, T cell proliferation assays, TCR stimulation, immunophenotyping\",\n      \"journal\": \"Immunity\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic knockout with defined cellular phenotype (enhanced T cell proliferation and autoimmunity), replicated across multiple assays\",\n      \"pmids\": [\"11754817\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"Combined loss of E2F1 and E2F2 results in profound effects on hematopoietic cell proliferation, B-cell differentiation, and T-cell tolerance/proliferation thresholds. E2F1/E2F2 double-knockout T cells exhibit more rapid entry into S phase and extensive proliferation in response to subthreshold antigenic stimulation, and double-knockout mice are highly predisposed to tumor development.\",\n      \"method\": \"E2f1/E2f2 double-knockout mice, cell cycle analysis, antigenic stimulation, tumor monitoring\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic double knockout with multiple orthogonal phenotypic readouts (proliferation, differentiation, tumorigenesis)\",\n      \"pmids\": [\"11713289\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"Drosophila E2f2 loss is viable but causes female sterility associated with failure to confine DNA synthesis to gene amplification sites in follicle cells. E2f2 mutant follicle cells inappropriately initiate genomic DNA replication instead of restricting synthesis to chorion gene amplification loci. Replication proteins ORC2, CDC45L, and ORC5 redistribute throughout the nucleus in E2f2 mutants. RT-PCR showed increased Orc5 mRNA in E2f2 mutants, indicating E2f2 represses pre-RC gene expression.\",\n      \"method\": \"Drosophila E2f2 mutant genetics, BrdU incorporation, immunofluorescence localization of ORC2/CDC45L/ORC5, RT-PCR\",\n      \"journal\": \"Development (Cambridge, England)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic loss-of-function with multiple orthogonal assays (replication, immunofluorescence localization, RT-PCR), Drosophila ortholog\",\n      \"pmids\": [\"11748144\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"Forced expression of E2F2 in PC12 cells (neuronal differentiation model) inhibited dedifferentiation and cell cycle re-entry upon NGF removal, and induced apoptosis instead. E2F2 converted reversibly differentiated neurons to a terminally differentiated, NGF-dependent state. Endogenous E2F2 levels increase in PC12 cells in response to NGF.\",\n      \"method\": \"Gain-of-function E2F2 overexpression in PC12 cells, NGF removal assay, cell cycle re-entry assays, apoptosis assays\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — gain-of-function with defined phenotype (blocked dedifferentiation, induced apoptosis), single lab\",\n      \"pmids\": [\"11526501\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"E2F1, E2F2, and E2F3 each contribute individually to Rb-deficiency-induced unscheduled proliferation in vivo. In the developing lens and retina of Rb-/- embryos, loss of E2F2 reduces ectopic DNA replication. E2F2 loss partially reduces unscheduled DNA replication in the CNS but has no effect on apoptosis in Rb-null embryos, demonstrating functional specificity among E2Fs.\",\n      \"method\": \"Compound Rb/E2f knockout mice, BrdU incorporation (ectopic proliferation), TUNEL (apoptosis), tissue-specific analysis\",\n      \"journal\": \"Cell growth & differentiation\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — compound genetic knockouts across multiple tissues with multiple phenotypic readouts\",\n      \"pmids\": [\"12065245\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"E2F2 and E2F3 can transcriptionally activate the p14(ARF) promoter, even in the absence of consensus E2F binding sites. Deletion and site-directed mutagenesis indicate E2F can regulate ARF both by direct DNA binding and indirectly, possibly via tethering by Sp1-like factors.\",\n      \"method\": \"Transient transfection reporter assays, promoter deletion and site-directed mutagenesis\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reporter assays with mutants in multiple conditions; single lab, one method type\",\n      \"pmids\": [\"11883935\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"ARF induction in response to oncogenic Ras and viral E1A oncoprotein is not significantly affected in E2F1-/-, E2F2-/-, or E2F1/2 double-knockout MEFs. ARF is upregulated normally in all cases, indicating ARF activation by oncogenic stress can occur by E2F1- and E2F2-independent mechanisms.\",\n      \"method\": \"Primary E2f1/E2f2 knockout MEFs, oncogenic Ras/E1A overexpression, ARF western blot and transcription assays\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic knockouts with oncogene induction; this is a negative result (ARF is NOT regulated by E2F2 in this context), single lab\",\n      \"pmids\": [\"12082524\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"E2F-2 binds to the ECE-1b promoter specifically, as demonstrated by EMSA. The -338A allele of the ECE-1b promoter shows increased affinity for E2F-2 compared to the -338C allele, and is associated with increased promoter activity in reporter assays.\",\n      \"method\": \"EMSA (electrophoretic mobility shift assay), transient transfection reporter assay\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct DNA binding by EMSA plus functional reporter assay, single lab\",\n      \"pmids\": [\"12566389\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"Drosophila RBF1 forms complexes with both E2F1/DP and E2F2/DP that cooperate to repress pre-replication complex (pre-RC) gene expression in follicle cells, thereby confining DNA synthesis to gene amplification sites. Reducing Orc2, Orc5, or Mcm2 gene dose by half suppresses the ectopic genomic replication phenotype of E2f2 mutants (genetic epistasis). E2F1 and E2F2 repressors function redundantly for some genes in the embryo but have context-dependent relative contributions.\",\n      \"method\": \"Drosophila genetics (epistasis by dosage reduction), RT-PCR, DNA microarray analysis of pre-RC gene transcripts\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — genetic epistasis with dosage reduction combined with transcriptome analysis; Drosophila ortholog with replicated findings\",\n      \"pmids\": [\"12612083\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"E2F2 transgenic mice (driven by Emu/pim1 promoter targeting thymic epithelial cells) develop cortical thymomas from 20 weeks, demonstrating that E2F2 deregulation promotes cell division and oncogenic transformation of thymic epithelial cells. In contrast, E2F1 transgenic mice do not develop cortical thymomas under the same promoter, indicating functional specificity.\",\n      \"method\": \"Transgenic mouse generation, tumor monitoring, immunohistochemistry (cytokeratin, ER-TR4), thymocyte subset analysis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — transgenic mouse model with defined tumor phenotype and histological characterization, single lab\",\n      \"pmids\": [\"14684733\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"Loss of both E2F1 and E2F2 in pancreatic cells leads to increased rates of DNA replication, apoptosis, and severe pancreatic atrophy. DNA replication and cell cycle control genes are upregulated in E2F1/E2F2 compound-mutant pancreas, indicating these genes are normally repressed by E2F1/E2F2 activity. E2F1/E2F2 activity is also required for maintenance of differentiated pancreatic phenotypes, as ductal and adipocyte marker genes were upregulated while pancreatic cell markers were downregulated.\",\n      \"method\": \"E2f1/E2f2 compound-mutant mice, gene expression profiling, histology, cell cycle analysis\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — compound genetic knockouts with gene expression profiling and multiple tissue phenotypes; replicated independently from PMID:15146237\",\n      \"pmids\": [\"14566047\", \"15146237\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"The Drosophila Myb-MuvB complex contains E2F2, DP, RBF1, RBF2, LIN-52, L(3)MBT, and Rpd3 (HDAC), identified by affinity chromatography fractionation of embryo extracts. Members of this complex localize to promoters and co-repress transcription of developmentally regulated genes.\",\n      \"method\": \"Affinity chromatography of Drosophila embryo extracts, co-purification, chromatin immunoprecipitation, transcriptional repression assays\",\n      \"journal\": \"Genes & development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — biochemical purification plus ChIP plus functional transcription repression assay; Drosophila ortholog, multiple orthogonal methods\",\n      \"pmids\": [\"15545624\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"HPV31 E7 activates E2F2 transcription specifically in differentiating (suprabasal) keratinocytes by inhibiting HDAC binding to the E2F2 promoter, as demonstrated by chromatin immunoprecipitation. siRNA knockdown of E2F2 confirmed that E2F2 expression is required for HPV replication but not for cell proliferation in this context.\",\n      \"method\": \"Chromatin immunoprecipitation (ChIP), siRNA knockdown, HPV replication assays, differentiated keratinocyte model\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — ChIP plus siRNA knockdown with direct functional readout (viral replication); multiple orthogonal methods, single lab\",\n      \"pmids\": [\"15861133\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Directed expression of E2F2 (but not E2F1, E2F3, or E2F5) in neonatal cardiomyocytes induces mitotic cell division without triggering apoptosis, while E2F1 and E2F3 induce both S-phase entry and apoptosis. E2F2 and E2F4 both induce S-phase entry, but only E2F2 results in actual mitotic division. E2F2/E2F4 expression down-regulate pro-apoptotic genes that are activated by E2F1/E2F3.\",\n      \"method\": \"Adenovirus-mediated gene transfer, BrdU incorporation, TUNEL apoptosis assay, quantitative RT-PCR of cell cycle and apoptotic genes\",\n      \"journal\": \"Circulation research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — comparative overexpression of multiple E2F family members with clear phenotypic specificity, multiple orthogonal readouts (BrdU, TUNEL, qRT-PCR)\",\n      \"pmids\": [\"15718499\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Overexpression of E2F2 in nonproliferating human corneal endothelial cells (ex vivo adenoviral delivery) induces G1-to-S phase progression and increased cell density without significant apoptosis, as shown by BrdU incorporation and specular microscopy.\",\n      \"method\": \"Adenoviral E2F2 overexpression in ex vivo human corneas, BrdU incorporation, specular microscopy, TUNEL assay\",\n      \"journal\": \"Investigative ophthalmology & visual science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct overexpression with BrdU and cell counting readouts; single lab, one model system\",\n      \"pmids\": [\"16186339\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"E2f1, E2f2, and E2f3 are required for oncogene-mediated transformation. Their combined inactivation elevates p21(CIP1) protein levels and causes cell cycle arrest at G1/S and G2/M. Loss of p21(CIP1) (but not p53) restores G1/S entry in triple-knockout cells. Loss of p53 (but not p21) allows cells to progress through both G1/S and mitosis and renders cells sensitive to transformation, indicating the critical function of E2F1-3 is in negative regulation of the p53-p21(CIP1) axis.\",\n      \"method\": \"Compound E2f conditional knockout MEFs, cell synchronization, p21/p53 inactivation by genetic crossing or dominant-negative, oncogene transformation assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — compound conditional knockouts combined with genetic epistasis (p21 and p53 inactivation) and transformation assays; multiple orthogonal methods\",\n      \"pmids\": [\"17008321\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"E2F2 functions as a transcriptional repressor of cell cycle genes to establish G0 quiescence. Loss of E2F2 causes T cells and MEFs to enter S phase early and undergo accelerated cell division. A large set of E2F target genes (Mcm's, cyclins, Cdc2a) that are normally silent in G0 are actively expressed in quiescent E2F2-knockout cells. ChIP analysis shows E2F2 occupies promoters of these genes in G0, confirming direct repressive role. Classic E2F activators E2F1 and E2F3 are largely dispensable for this quiescence maintenance.\",\n      \"method\": \"E2f2 knockout mice, S phase entry assays (BrdU), ChIP, shRNA knockdown of E2F3, compound E2F1/E2F2 double-knockout\",\n      \"journal\": \"Cell cycle (Georgetown, Tex.)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — genetic knockout combined with ChIP (direct promoter binding) and orthogonal shRNA knockdown; multiple labs confirming quiescence role\",\n      \"pmids\": [\"19066456\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Combined inactivation of E2f1, E2f2, and E2f3 in MEFs activates p53 and induces p21(CIP1), leading to inhibition of CDK activity and Rb phosphorylation, Rb/E2F-mediated target gene repression, and severe proliferative block. Inactivation of p53 in E2f1/2/3-deficient cells prevents p21 induction, restores CDK activity and Rb phosphorylation, and allows near-normal E2F target gene expression and response to growth signals.\",\n      \"method\": \"Conditional triple knockout MEFs, p53 conditional knockout, immunoblot for CDK activity and Rb phosphorylation, RT-PCR of E2F targets\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — conditional compound knockouts with genetic rescue (p53 deletion), multiple biochemical readouts\",\n      \"pmids\": [\"17167174\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Loss of E2f2 accelerates Myc-driven T cell lymphomagenesis in a bitransgenic mouse model, while loss of E2f1 or E2f3 has no significant effect. Loss of a single copy of E2f2 also accelerates tumorigenesis (haploinsufficiency). Myc-overexpressing T cells are more resistant to apoptosis in the absence of E2f2, and reintroduction of E2F2 into tumor cells increases apoptosis and inhibits tumorigenesis, identifying E2f2 as a tumor suppressor that modulates apoptosis.\",\n      \"method\": \"Bitransgenic mouse model (MMTV-Myc × E2f KO), tumor progression monitoring, apoptosis assays, E2F2 reintroduction into tumor cells\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — in vivo bitransgenic genetic model with rescue experiment (E2F2 reintroduction), multiple readouts\",\n      \"pmids\": [\"17881568\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"p53 and Rb (via E2Fs) repress survivin transcription in normal human melanocytes through direct promoter binding. E2F2 specifically binds a novel E2F site in the survivin promoter and negatively regulates survivin expression. Mutation of either the p53 or E2F binding sites is sufficient to increase survivin promoter activity.\",\n      \"method\": \"ChIP assay, promoter-reporter assays with site-directed mutation, siRNA knockdown of E2F2\",\n      \"journal\": \"Carcinogenesis\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP plus reporter assays with mutation, single lab\",\n      \"pmids\": [\"17916908\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"E2f-2 is the major pRb-associated E2F in end-stage red cells (erythroblasts) and the predominant E2F detected at key target gene promoters during terminal erythroid differentiation. E2f-2 loss restores terminal erythroid maturation (including enucleation) to Rb-null red cells. Deletion of E2f-2 also extends the lifespan of Rb-null mice. Aberrant S-phase entry of Rb-null erythroblasts is inhibited by E2f-2 deletion.\",\n      \"method\": \"Compound Rb/E2f-2 knockout mice, ChIP at target gene promoters, cell cycle analysis, enucleation assays, survival analysis\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — compound knockout with ChIP and multiple phenotypic readouts (maturation, enucleation, lifespan); orthogonally confirmed\",\n      \"pmids\": [\"17923680\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"EKLF/KLF1 directly occupies the proximal E2f2 promoter in erythroid progenitor cells in vivo. Loss of EKLF reduces E2f2 mRNA and protein levels in early erythroid progenitors, leading to a delay in G1-to-S phase transition. EKLF binding sites in the E2f2 promoter lie in a region of EKLF-dependent DNase I sensitivity.\",\n      \"method\": \"Eklf-knockout mice, ChIP (EKLF occupancy at E2f2 promoter), DNase I hypersensitivity, RT-PCR, western blot, cell cycle analysis\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — ChIP for direct occupancy combined with knockout phenotype and DNase I sensitivity; multiple orthogonal methods\",\n      \"pmids\": [\"18852285\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Directed expression of E2F2 in adult mouse hearts (via adenoviral vector) induces proliferation of cardiomyocytes in vivo, without increasing apoptosis. E2F2 in vivo causes strong induction of cyclin A and cyclin E while not affecting CDK inhibitor p21. E2F2 also down-regulates pro-apoptotic genes caspase-6 and apaf-1.\",\n      \"method\": \"Adenoviral E2F2 delivery in mice, histological section analysis, quantitative RT-PCR, western blot of cell cycle regulatory proteins\",\n      \"journal\": \"Cardiovascular research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo overexpression with histology and gene expression analysis; single lab replicating prior in vitro finding\",\n      \"pmids\": [\"18628254\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"GATA-1 forms a tricomplex with pRb and E2F-2 during terminal erythroid differentiation. This interaction requires a LXCXE motif conserved in GATA-1 orthologs (absent from other GATA family members). The GATA-1/pRb/E2F-2 complex stalls cell proliferation and steers erythroid precursors toward terminal differentiation. FOG-1 can disrupt this complex by displacing pRb/E2F-2 from GATA-1. A GATA-1 mutant unable to bind pRb fails to inhibit proliferation and causes embryonic lethality by anemia.\",\n      \"method\": \"Co-immunoprecipitation, domain mapping (LXCXE motif), GATA-1 mutant mouse models, in vitro disruption assay with FOG-1, cell proliferation assays\",\n      \"journal\": \"PLoS biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — reciprocal Co-IP, domain mutant, in vivo rescue/lethality, in vitro disruption; multiple orthogonal methods in a single rigorous study\",\n      \"pmids\": [\"19513100\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"EKLF/KLF1 directly activates E2f2 through a novel intronic enhancer containing conserved CACC, GATA, and E-BOX elements. EKLF occupies this E2f2 enhancer in vivo (ChIP). Loss of EKLF causes aberrant S-phase entry, and additional genetic depletion of Rb (epistasis) partially restores normal cell cycle dynamics, establishing a causal link between reduced E2f2 and the EKLF cell cycle defect.\",\n      \"method\": \"ChIP (EKLF occupancy at E2f2 intronic enhancer), Rb/EKLF double-knockout epistasis, cell cycle analysis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — ChIP plus genetic epistasis; replicates and extends PMID:18852285 findings with enhancer identification\",\n      \"pmids\": [\"19457859\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"E2F2 directly binds the ECE-1b promoter in endothelial cells (confirmed by ChIP) and activates ECE-1b transcription (confirmed by promoter-reporter assay). Loss of E2F2 leads to decreased ECE-1b mRNA, elevated membranous ECE-1 isoforms (ECE-1a, -1c, -1d), deregulated ECE-1 activity, increased vascular contractility, and higher blood pressure in E2F2-null mice. Sam68 co-immunoprecipitates with E2F2, occupies the ECE-1b promoter (ChIP), and represses E2F2-mediated ECE-1b transcription.\",\n      \"method\": \"ChIP (E2F2 and Sam68 at ECE-1b promoter), promoter-reporter assays, co-immunoprecipitation (Sam68-E2F2), tail-cuff blood pressure measurement in E2F2-null mice, ex vivo aortic ring contractility\",\n      \"journal\": \"Circulation\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — ChIP, co-IP, promoter-reporter, and in vivo physiological phenotype; multiple orthogonal methods\",\n      \"pmids\": [\"19752322\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"miR-24 directly regulates E2F2 expression by binding seedless but highly complementary sequences in the E2F2 3'UTR. Enhanced proliferation from antagonizing miR-24 is abrogated by knocking down E2F2, and miR-24-insensitive E2F2 rescues miR-24-mediated inhibition of proliferation, demonstrating that E2F2 is a critical functional target of miR-24.\",\n      \"method\": \"miRNA overexpression/antagonism, E2F2 knockdown rescue experiment, miR-24-resistant E2F2 rescue, microarray-based target identification\",\n      \"journal\": \"Molecular cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple complementary experiments including rescue with miRNA-insensitive E2F2 and knockdown epistasis\",\n      \"pmids\": [\"19748357\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"E2F1/E2F2 deficiency in differentiating bone marrow-derived macrophages results in accelerated DNA replication and cellular division, accompanied by early expression of DNA replication and cell cycle regulators. Rapid proliferation is followed by induction of a DNA damage response and p21(CIP1)-dependent senescence. Senescence is not triggered in the absence of DNA replication, establishing a causal link between E2F1/E2F2 loss, DNA hyper-replication, and senescence.\",\n      \"method\": \"Compound E2f1/E2f2 knockout bone marrow differentiation, BrdU incorporation, gene expression profiling, aphidicolin (replication inhibitor) experiment, p21 pathway analysis\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — compound knockout with pharmacological intervention (aphidicolin) to establish causal link; multiple orthogonal methods\",\n      \"pmids\": [\"20676136\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Drosophila dE2F2 (E2F2), together with net E2F activity (assessed by dDp mutation), inhibits p53-independent IR-induced apoptosis in larval imaginal discs. dE2F1 promotes IR-induced p53-independent apoptosis and is required for transcriptional induction of the pro-apoptotic gene hid after irradiation when p53 is mutated. These two E2F homologs have opposing effects on p53-independent apoptosis.\",\n      \"method\": \"Drosophila genetics (E2f2 and Dp mutants), transcriptional reporters (hid), irradiation, p53 mutation background\",\n      \"journal\": \"Developmental biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic mutants with transcriptional reporter readout in Drosophila; Drosophila ortholog, single lab\",\n      \"pmids\": [\"20659447\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"E2F2 is required for adult hepatocyte proliferation and timely liver regeneration after partial hepatectomy. E2F2-knockout hepatocytes exhibit a reduced rate of S-phase entry and delayed liver regeneration. Transcriptome analysis shows that genes for cell cycle, apoptosis, and wound-healing response are absent in posthepatectomized E2F2-/- mice.\",\n      \"method\": \"E2f2-knockout mice, partial hepatectomy model, BrdU incorporation, transcriptome analysis\",\n      \"journal\": \"American journal of physiology. Gastrointestinal and liver physiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — knockout mouse with defined phenotype (delayed regeneration, reduced S-phase) plus transcriptome analysis; single lab\",\n      \"pmids\": [\"21527726\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"E2F2 occupies promoters of a large number of cell cycle and DNA metabolism genes during T cell quiescence (ChIP-chip genome-wide analysis). E2F2 and CREB cooperate in transcriptional repression of a subset of target genes (Mcm5, Chk1). CREB knockdown (siRNA), dominant-negative KCREB expression, or mutation of the CRE motif in the Mcm5 promoter relieves E2F2-mediated repression. This repression is retinoblastoma-independent.\",\n      \"method\": \"ChIP-chip (genome-wide), expression profiling, luciferase reporter assays, siRNA knockdown (CREB), dominant-negative CREB, CRE site mutation\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — ChIP-chip combined with multiple orthogonal functional assays (siRNA, dominant-negative, promoter mutation); single lab but highly rigorous\",\n      \"pmids\": [\"24038359\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Drosophila Myb-null cytokinesis failure (binucleate cells) is suppressed by loss of E2F2 or Mip130 (dREAM complex subunits), indicating that transcriptional repression by the dREAM complex requires E2F2 for its full activity. The Myb-null phenotype is sensitive to dosage of E2F2, Mip120, Caf1, and Lin-52. Reduction of histone variant H2Av/H2A.z also suppresses the Myb-null phenotype, implicating H2A.z in dREAM-mediated transcriptional repression.\",\n      \"method\": \"Drosophila genetics (Myb-null with E2F2/dREAM subunit mutations), quantitative phenotypic readout (binucleate cell frequency), H2Av dosage reduction\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis in Drosophila with clear quantitative readout; Drosophila ortholog, single lab\",\n      \"pmids\": [\"23438598\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"E2f2 (but not E2f1 or E2f3) is required and sufficient for cone photoreceptor apoptosis in Rb/p107 double-null retinas, demonstrating a direct, E2f1-independent apoptotic function. E2f2-induced cone death is p53-dependent (in contrast to E2f1-dependent apoptosis in other neurons which is p53-independent). E2f2 deletion rescues cone survival in Rb/p107-null retinas.\",\n      \"method\": \"Compound Rb/p107/E2f knockout mice, TUNEL apoptosis assay, genetic rescue experiments\",\n      \"journal\": \"Cell death and differentiation\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — compound genetic knockouts with clear rescue; multiple E2f family members tested to establish specificity\",\n      \"pmids\": [\"23558950\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"ALY (THO complex 4) associates with DNA-bound E2F2 and represses its transcriptional activity. ALY influences the expression of over 400 genes, including 98 genes with consensus E2F motifs, as determined by expression microarrays in ALY-overexpressing or ALY-silenced HEK293T cells expressing E2F2.\",\n      \"method\": \"Co-immunoprecipitation (ALY-E2F2 interaction), expression microarrays (ALY overexpression and siRNA silencing in E2F2-expressing cells)\",\n      \"journal\": \"Molecular & cellular proteomics : MCP\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP plus microarray functional readout; single lab\",\n      \"pmids\": [\"23297349\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"Loss of E2F1 and E2F2 together (but not individually) prevents replicative stress in the pancreas. Combined inactivation leads to unscheduled DNA replication, DNA damage response activation, and p53-mediated mitochondrial apoptosis causing pancreatic atrophy and diabetes. Suppression of DNA replication in vivo with aphidicolin significantly inhibits the p53 pathway in double-knockout pancreas. Targeted p53 inactivation abrogates cellular apoptosis and prevents organ involution, establishing a causal E2F-p53 regulatory axis.\",\n      \"method\": \"E2f1/E2f2 double-knockout mice, aphidicolin treatment (in vivo replication suppression), p53 triple-knockout mice, DNA damage marker analysis, apoptosis assays\",\n      \"journal\": \"Cell death and differentiation\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — compound knockout with pharmacological intervention plus genetic epistasis (p53 deletion); multiple orthogonal approaches\",\n      \"pmids\": [\"25656653\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"E2F1 and E2F2 are transcriptionally induced in neuronal cells after DNA damage (genotoxic treatment), leading to increased protein levels via de novo synthesis. E2F1/E2F2 accumulate at sites of oxidative and UV-induced DNA damage and interact with γH2AX. E2F2 promotes Rad51 foci formation, interacts with GCN5 acetyltransferase, and induces histone acetylation following genotoxic insult. Ablation of E2F1 and E2F2 leads to DNA lesion accumulation, increased apoptosis, and reduced DNA repair capacity.\",\n      \"method\": \"Genotoxic treatment, de novo protein synthesis assays, co-immunoprecipitation (E2F2-γH2AX and E2F2-GCN5), immunofluorescence (E2F2 accumulation at damage sites, Rad51 foci), siRNA knockdown, cell viability assays\",\n      \"journal\": \"Cell cycle (Georgetown, Tex.)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — Co-IP with damage-response factors, immunofluorescence localization at damage sites, functional ablation; multiple orthogonal methods\",\n      \"pmids\": [\"25892555\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"E2F-2 is required for efficient erythroblast enucleation and nuclear condensation during terminal erythroid differentiation. Citron Rho-interacting kinase (CRIK) is induced in erythroblasts in an E2F-2-dependent manner, and CRIK activity promotes efficient erythroblast enucleation and nuclear condensation. E2F-2 deletion impairs nuclear condensation in mature erythroblasts.\",\n      \"method\": \"E2f-2 knockout mice, enucleation assays, transcriptome profiling of E2F-2-null erythroblasts, functional inhibition/activation of CRIK\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — knockout mice with transcriptome profiling and functional CRIK assays; single lab\",\n      \"pmids\": [\"27795297\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"BRD4 inhibition (by JQ1) identifies E2F2 as a direct downstream target of BRD4 in liver cancer cells, confirmed by ChIP assay. Loss-of-function of E2F2 in liver cancer cells recapitulates BRD4 inhibition effects on cell cycle arrest.\",\n      \"method\": \"ChIP assay (BRD4 at E2F2 promoter), siRNA knockdown of E2F2, JQ1 treatment with gene expression analysis\",\n      \"journal\": \"Oncotarget\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP plus functional loss-of-function; single lab\",\n      \"pmids\": [\"27081696\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"E2F2 directly binds the promoters of STAT1 and MyD88 (confirmed by ChIP and luciferase assays) and upregulates their expression, facilitating formation of STAT1/MyD88 complexes and AKT activation. This E2F2-STAT1/MyD88-AKT axis drives inflammatory cytokine (IL-1α, IL-1β, TNF-α) production in rheumatoid arthritis synovial fibroblasts. Silencing STAT1/MyD88 or inactivating AKT attenuates cytokine induction by E2F2.\",\n      \"method\": \"ChIP-PCR, luciferase reporter assay, co-immunoprecipitation (STAT1-MyD88 complex), western blot, E2f2-knockout mouse collagen arthritis model, siRNA knockdown\",\n      \"journal\": \"Arthritis research & therapy\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — ChIP, Co-IP, reporter assay, in vivo knockout model, and epistasis by silencing downstream effectors; multiple orthogonal methods\",\n      \"pmids\": [\"30286793\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"E2F2 directly binds the CPT2 promoter (confirmed by ChIP) and represses its transcription, inhibiting fatty acid oxidation. E2f2-knockout mice show enhanced fatty acid oxidation and increased CPT2 expression. E2f2 knockdown in liver recapitulates this, while E2f2 overexpression has opposing effects. This E2F2-CPT2 axis creates a lipid-rich environment promoting hepatocarcinogenesis.\",\n      \"method\": \"ChIP (E2F2 at CPT2 promoter), E2f2-knockout mice, shRNA knockdown in liver, E2f2 overexpression, fatty acid oxidation assays, DEN/HFD hepatocarcinogenesis model\",\n      \"journal\": \"Cancer research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — ChIP for direct promoter binding combined with knockout, knockdown, overexpression and in vivo metabolic assays; multiple orthogonal methods\",\n      \"pmids\": [\"33771899\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"E2F2 transcriptionally activates PFKFB4 by directly binding its promoter (confirmed by ChIP and luciferase assay), activating the PI3K/AKT signaling pathway to promote glioma cell glycolysis and malignant progression. PFKFB4 knockdown mitigates E2F2-driven glioma metastasis and glycolysis.\",\n      \"method\": \"ChIP, luciferase assay, PFKFB4 knockdown, E2F2 overexpression/knockdown, glycolysis assays, in vivo tumor growth/metastasis models\",\n      \"journal\": \"Life sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP plus reporter assay plus functional epistasis; single lab\",\n      \"pmids\": [\"33774025\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"B-Myb directly transactivates E2F2, and E2F2 in turn directly transactivates B-Myb, forming a reciprocal feed-forward transcriptional loop in colorectal cancer. B-Myb and E2F2 physically interact and co-occupy each other's promoters. Both B-Myb and E2F2 are required for ERK and AKT signaling pathway activation in colorectal cancer cells.\",\n      \"method\": \"Co-immunoprecipitation (B-Myb/E2F2 interaction), ChIP (B-Myb and E2F2 at each other's promoters), luciferase reporter assay, siRNA knockdown, in vivo orthotopic tumor model\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP, reciprocal ChIP, reporter assay, knockdown; multiple orthogonal methods\",\n      \"pmids\": [\"34316028\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"E2F2 undergoes ubiquitination and proteasomal degradation via the atypical E3 ligase ZFP91. The natural product bufalin promotes E2F2-ZFP91 complex formation (identified by human proteome microarray and Co-IP/SILAC quantitative proteomics), leading to E2F2 polyubiquitination via K48-linked ubiquitin chains and degradation. E2F2 degradation causes transcriptional suppression of oncogenes including c-Myc, CCNE1, CCNE2, MCM5 and CDK1.\",\n      \"method\": \"Human proteome microarray, Co-IP with SILAC-based quantitative proteomics, ubiquitination assay (K48-linkage), proteasome inhibitor experiments, gene expression analysis\",\n      \"journal\": \"EBioMedicine\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — proteome microarray plus Co-IP/quantitative proteomics plus ubiquitination chain analysis; multiple orthogonal methods identifying E3 ligase and mechanism\",\n      \"pmids\": [\"36375317\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Loss of E2F2 in E2F2-deficient T lymphocytes leads to deregulated Aryl-hydrocarbon-receptor (Ahr) pathway. Proliferating E2F2-/- T cells express significantly higher levels of Aip, Ahr, and Arnt. E2F2 directly regulates the Aip gene promoter (binding confirmed), and E2F2-/- T cells show increased sensitivity to TCDD-triggered apoptosis. ChIP showed E2F2 binding to Ahr and Arnt promoters as well.\",\n      \"method\": \"Differential proteomics (E2F2-/- vs WT T cells), ChIP (E2F2 at Aip/Ahr/Arnt promoters), TCDD treatment apoptosis assay\",\n      \"journal\": \"Molecular & cellular proteomics : MCP\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — proteomics plus ChIP plus functional apoptosis assay; single lab\",\n      \"pmids\": [\"20573986\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"E2F2 forms part of a core transcription regulatory circuitry with B-Myb and FOXM1 in lung adenocarcinoma; these three factors positively correlate in expression, physically associate, mutually transactivate each other, and regulate similar downstream gene cascades. E2F2 promotes LUAD growth in orthotopic mouse models.\",\n      \"method\": \"Co-immunoprecipitation (E2F2/B-Myb/FOXM1 interaction), ChIP, luciferase reporter assay, siRNA knockdown, orthotopic mouse tumor model\",\n      \"journal\": \"International journal of biological sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP, ChIP, and reporter assays confirming physical and functional interaction; single lab\",\n      \"pmids\": [\"35844795\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"E2F2 is a transcription factor that functions primarily as a transcriptional repressor of cell cycle genes (including Mcm's, cyclins, and Cdc2a) to establish and maintain cellular quiescence (G0), forms a stable tricomplex with pRb and GATA-1 during erythroid differentiation, represses pre-replication complex gene expression in a conserved Myb-MuvB/dREAM complex, directly binds and represses the CPT2 promoter to regulate fatty acid oxidation, activates ECE-1b transcription in endothelial cells (regulated by Sam68 co-repressor) to control blood pressure, and is degraded via K48-linked ubiquitination by the atypical E3 ligase ZFP91; its loss in vivo leads to enhanced lymphocyte proliferation and autoimmunity, accelerated Myc-driven tumorigenesis, defective erythroid enucleation, and replicative stress-driven p53-dependent apoptosis, while its overexpression uniquely drives cardiomyocyte mitotic division without apoptosis.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"E2F2 is a sequence-specific transcription factor of the E2F family that binds DNA as a heterodimer and contains conserved DNA-binding and retinoblastoma (Rb)-binding domains [#0], functioning predominantly as a transcriptional repressor that establishes and maintains cellular quiescence (G0) by occupying and silencing cell-cycle and DNA-metabolism gene promoters (Mcm's, cyclins, Cdc2a) in resting cells [#18, #32]. In vivo, this repressive activity enforces immunologic self-tolerance and proliferative restraint: loss of E2F2 lowers the lymphocyte activation threshold and produces autoimmunity, and combined loss with E2F1 drives accelerated, unscheduled DNA replication that triggers a DNA-damage response and p53/p21-dependent apoptosis or senescence [#2, #29, #36]. E2F2-mediated repression operates through conserved corepressor machinery — within the Drosophila Myb-MuvB/dREAM complex containing DP, RBF1/RBF2, LIN-52, L(3)MBT and Rpd3/HDAC [#13, #33], and in cooperation with partners such as CREB at human cell-cycle promoters in an Rb-independent manner [#32]. Beyond cell-cycle control, E2F2 acts as a context-specific transcriptional activator, directly binding and inducing the ECE-1b promoter in endothelial cells (with Sam68 as a corepressor) to regulate vascular tone and blood pressure [#27], and repressing the CPT2 promoter to limit fatty acid oxidation [#41]. During terminal erythroid differentiation, E2F2 is the predominant pRb-associated E2F and assembles a pRb/E2F2/GATA-1 tricomplex that halts proliferation and promotes maturation and enucleation [#22, #25, #38]. E2F2 is itself a node of regulation — transcriptionally controlled by Myc-responsive and E2F sites in its promoter [#1] and by EKLF/KLF1 in erythroid cells [#23, #26], post-transcriptionally targeted by miR-24 [#28], and degraded via K48-linked polyubiquitination by the atypical E3 ligase ZFP91 [#44]. Functionally, E2F2 behaves as a tumor suppressor whose loss accelerates Myc-driven lymphomagenesis and modulates apoptosis [#20], yet acts oncogenically in other contexts by driving glycolytic and proliferative programs [#42, #43].\",\n  \"teleology\": [\n    {\n      \"year\": 1993,\n      \"claim\": \"Established E2F2 as a distinct E2F-family transcription factor, defining its DNA-binding and Rb-binding domains and its requirement to function as a DNA-binding heterodimer.\",\n      \"evidence\": \"cDNA cloning, in vitro DNA-binding and complementation assays with HeLa E2F components, antibody cross-reactivity\",\n      \"pmids\": [\"8246995\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not define endogenous target genes or in vivo function\", \"Heterodimer partner (DP) not directly mapped here\"]\n    },\n    {\n      \"year\": 1997,\n      \"claim\": \"Clarified how E2F2 expression is itself controlled, showing its promoter integrates Myc-responsive activating E-boxes and repressive E2F sites for growth-dependent regulation.\",\n      \"evidence\": \"Promoter-reporter assays with deletion/mutation under growth stimulation\",\n      \"pmids\": [\"9271400\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Reporter-based, not endogenous chromatin context\", \"Identity of repressive E2F at its own promoter unresolved\"]\n    },\n    {\n      \"year\": 2001,\n      \"claim\": \"Defined the in vivo physiological role of E2F2 as a repressor enforcing immune self-tolerance and proliferative restraint, reframing it from an activator to a repressor.\",\n      \"evidence\": \"E2f2-knockout and E2f1/E2f2 double-knockout mice, T-cell proliferation/tolerance assays, tumor monitoring; Drosophila E2f2 loss-of-function with replication assays\",\n      \"pmids\": [\"11754817\", \"11713289\", \"11748144\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct promoter occupancy not yet shown in mammalian cells\", \"Corepressor complexes mediating repression not identified\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Demonstrated functional specificity among E2Fs in vivo, with E2F2 selectively contributing to Rb-loss-driven ectopic replication in defined tissues but not uniformly to apoptosis or ARF induction.\",\n      \"evidence\": \"Compound Rb/E2f knockout mice with BrdU/TUNEL; E2f1/2 knockout MEFs with oncogenic Ras/E1A and ARF assays; ARF promoter reporter analysis\",\n      \"pmids\": [\"12065245\", \"11883935\", \"12082524\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanistic basis of E2F2 tissue specificity unresolved\", \"Mixed activator/repressor behavior at ARF not reconciled\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Showed E2F2 represses pre-replication-complex genes through a conserved RBF-containing repressor mechanism and that E2F2 deregulation can transform cells, while also acting as a sequence-specific activator at ECE-1b.\",\n      \"evidence\": \"Drosophila genetic epistasis with pre-RC dosage and microarray; E2F2 transgenic mice developing thymomas; compound mutant pancreas profiling; EMSA/reporter at ECE-1b promoter\",\n      \"pmids\": [\"12612083\", \"14684733\", \"14566047\", \"15146237\", \"12566389\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Full subunit composition of the repressor complex not yet defined\", \"Activator versus repressor switch determinants unknown\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Identified the molecular machinery for E2F2 repression by purifying the Myb-MuvB/dREAM complex containing E2F2, DP, RBF1/RBF2, LIN-52, L(3)MBT, and the HDAC Rpd3.\",\n      \"evidence\": \"Affinity chromatography of Drosophila embryo extracts, ChIP, transcriptional repression assays\",\n      \"pmids\": [\"15545624\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Human ortholog complex composition not directly demonstrated here\", \"Recruitment hierarchy of subunits to promoters not resolved\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Revealed unique E2F2 cell-fate outputs — viral exploitation of E2F2 induction for replication and an apoptosis-free proliferative program in cardiomyocytes that distinguishes it from E2F1/E2F3.\",\n      \"evidence\": \"ChIP and siRNA in differentiating keratinocytes with HPV replication assays; comparative adenoviral E2F overexpression in cardiomyocytes and corneal endothelium with BrdU/TUNEL/qRT-PCR\",\n      \"pmids\": [\"15861133\", \"15718499\", \"16186339\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular basis for E2F2 suppressing apoptosis while inducing division not fully defined\", \"Target genes distinguishing E2F2 from E2F1 incompletely mapped\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Defined E2F2 as a direct repressor maintaining quiescence by occupying cell-cycle gene promoters, and established that combined E2F1-3 loss enforces arrest through the p53-p21 axis.\",\n      \"evidence\": \"E2f2 knockout mice with ChIP and BrdU; conditional triple-knockout MEFs with p53/p21 genetic epistasis and CDK/Rb biochemistry; bitransgenic Myc model with E2F2 reintroduction; survivin promoter ChIP/reporter\",\n      \"pmids\": [\"19066456\", \"17008321\", \"17167174\", \"17881568\", \"17916908\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Corepressors at quiescence promoters not all identified\", \"Relationship between repressive and pro-apoptotic functions unresolved\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Connected E2F2 to erythroid cell-cycle control upstream and downstream — as an EKLF/KLF1 transcriptional target driving G1/S progression and as an in vivo cardiomyocyte proliferation inducer that downregulates pro-apoptotic genes.\",\n      \"evidence\": \"Eklf-knockout mice with ChIP and DNase I hypersensitivity; adenoviral E2F2 delivery in adult mouse hearts with histology and qRT-PCR\",\n      \"pmids\": [\"18852285\", \"18628254\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether EKLF-E2F2 axis generalizes beyond erythroid lineage unknown\", \"Mechanism of pro-apoptotic gene downregulation by E2F2 not defined\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Resolved the erythroid pRb/E2F2/GATA-1 tricomplex and an EKLF intronic enhancer driving E2F2, and defined E2F2 as a direct ECE-1b activator controlling blood pressure with Sam68 as corepressor and miR-24 as a post-transcriptional regulator.\",\n      \"evidence\": \"Co-IP and LXCXE domain mapping with GATA-1 mutant mice; ChIP and Rb/EKLF epistasis at E2f2 enhancer; ChIP/co-IP/reporter and in vivo blood pressure in E2F2-null mice; miR-24 3'UTR rescue experiments\",\n      \"pmids\": [\"19513100\", \"19457859\", \"19752322\", \"19748357\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How the same factor switches between repression and activation at different promoters unresolved\", \"Sam68 mechanism of corepression not structurally defined\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Established a causal chain from E2F1/E2F2 loss through DNA hyper-replication to senescence, and extended E2F2 targets to the Ahr xenobiotic pathway and p53-independent apoptosis regulation.\",\n      \"evidence\": \"Compound knockout bone-marrow differentiation with aphidicolin; differential proteomics and ChIP at Aip/Ahr/Arnt with TCDD apoptosis; Drosophila E2f2/Dp genetics on IR-induced apoptosis\",\n      \"pmids\": [\"20676136\", \"20573986\", \"20659447\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct versus indirect contribution of E2F2 to senescence not separated from E2F1\", \"Ahr regulation in other cell types untested\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Identified E2F2's combinatorial repression partners (CREB) genome-wide and an unexpected role in the DNA-damage response, with E2F2 localizing to lesions, interacting with γH2AX and GCN5, and promoting Rad51 foci and repair.\",\n      \"evidence\": \"ChIP-chip with CREB siRNA/dominant-negative and promoter mutation; compound Rb/p107/E2f knockout retinas with TUNEL rescue; co-IP and immunofluorescence at damage sites; ALY co-IP and microarray; Drosophila dREAM/Myb epistasis\",\n      \"pmids\": [\"24038359\", \"23558950\", \"25892555\", \"23297349\", \"23438598\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether DNA-repair role is transcriptional or direct chromatin function not resolved\", \"Stoichiometry of E2F2 with CREB/ALY corepressors unknown\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Cemented the E2F-p53 axis in vivo, showing pancreatic involution from E2F1/E2F2 loss arises causally from replicative stress driving p53-mediated mitochondrial apoptosis.\",\n      \"evidence\": \"E2f1/E2f2 double-knockout mice with in vivo aphidicolin and p53 genetic inactivation, DNA-damage and apoptosis assays\",\n      \"pmids\": [\"25656653\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Tissue-selectivity of the replicative-stress phenotype unexplained\", \"E2F2-specific versus shared E2F1 contribution not separated\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Linked E2F2 mechanistically to erythroblast enucleation via CRIK induction and identified E2F2 as a direct BRD4 transcriptional target in liver cancer.\",\n      \"evidence\": \"E2f-2 knockout erythroblast enucleation assays with transcriptome and CRIK functional manipulation; BRD4/JQ1 ChIP and E2F2 loss-of-function in liver cancer cells\",\n      \"pmids\": [\"27795297\", \"27081696\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct E2F2 occupancy at CRIK not shown\", \"BRD4-E2F2 axis tested in a single cancer context\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Revealed an activating, pro-inflammatory E2F2 program in rheumatoid arthritis, directly inducing STAT1 and MyD88 to drive an AKT-dependent cytokine cascade.\",\n      \"evidence\": \"ChIP-PCR, luciferase, co-IP of STAT1/MyD88, E2f2-knockout collagen arthritis model, downstream effector silencing\",\n      \"pmids\": [\"30286793\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How E2F2 switches to an activator at inflammatory promoters not defined\", \"Generalizability beyond synovial fibroblasts untested\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Expanded E2F2's direct target repertoire into metabolism and oncogenic signaling — repressing CPT2 to suppress fatty acid oxidation, activating PFKFB4 to drive glycolysis, and forming a reciprocal feed-forward loop with B-Myb.\",\n      \"evidence\": \"ChIP with knockout/knockdown/overexpression and in vivo metabolic and tumor models for CPT2; ChIP/reporter/knockdown for PFKFB4 glycolysis; reciprocal co-IP/ChIP for B-Myb loop\",\n      \"pmids\": [\"33771899\", \"33774025\", \"34316028\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Determinants of E2F2 repressor-versus-activator behavior at metabolic genes unresolved\", \"Direct partners stabilizing E2F2 on these promoters not mapped\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Defined E2F2 degradation by the atypical E3 ligase ZFP91 via K48-linked ubiquitination and placed E2F2 within a B-Myb/FOXM1 core transcriptional circuit in cancer.\",\n      \"evidence\": \"Proteome microarray, co-IP/SILAC proteomics, K48-ubiquitination assays, bufalin treatment; co-IP/ChIP/reporter and orthotopic models for the B-Myb/FOXM1 circuit\",\n      \"pmids\": [\"36375317\", \"35844795\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological signals controlling ZFP91-E2F2 degradation beyond bufalin unknown\", \"Structural basis of ZFP91 substrate recognition not defined\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"It remains unresolved what molecular determinants switch E2F2 between transcriptional repressor (cell-cycle, CPT2) and activator (ECE-1b, STAT1/MyD88, PFKFB4) on different promoters, and how corepressor versus coactivator recruitment is selected in a given cell context.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unifying mechanism distinguishing activator from repressor promoters\", \"Cell-type-specific cofactor determinants undefined\", \"Structural basis of context-dependent partner selection unknown\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140110\", \"supporting_discovery_ids\": [0, 18, 27, 32, 40, 41]},\n      {\"term_id\": \"GO:0003677\", \"supporting_discovery_ids\": [0, 9, 27, 41]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [13, 18, 32, 37]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1640170\", \"supporting_discovery_ids\": [18, 19, 36]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [0, 18, 27, 41]},\n      {\"term_id\": \"R-HSA-73894\", \"supporting_discovery_ids\": [37]},\n      {\"term_id\": \"R-HSA-5357801\", \"supporting_discovery_ids\": [20, 34, 36]}\n    ],\n    \"complexes\": [\n      \"Myb-MuvB/dREAM complex\",\n      \"pRb/E2F2/GATA-1 tricomplex\"\n    ],\n    \"partners\": [\n      \"RB1\",\n      \"GATA1\",\n      \"CREB\",\n      \"Sam68 (KHDRBS1)\",\n      \"ZFP91\",\n      \"B-Myb (MYBL2)\",\n      \"FOXM1\",\n      \"GCN5 (KAT2A)\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}