{"gene":"TCF7L1","run_date":"2026-06-10T10:51:54","timeline":{"discoveries":[{"year":2013,"finding":"β-catenin inactivates Tcf7l1 by removing it from DNA (rather than switching it to a coactivator complex), which leads to Tcf7l1 protein degradation. Mouse genetic experiments demonstrated that Tcf7l1 inactivation is the only required effect of the Tcf7l1–β-catenin interaction.","method":"Co-immunoprecipitation, DNA-binding assays, mouse genetic (knockout/knock-in) epistasis experiments","journal":"Cell Reports","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal functional genetics plus DNA-binding assays; multiple orthogonal methods; independently interpreted alongside other labs' work","pmids":["23810553"],"is_preprint":false},{"year":2013,"finding":"Tcf7l1 repressor activity is necessary in pluripotent epiblast cells for rapid lineage specification during gastrulation; Tcf7l1−/− embryos show delayed mesoderm specification uncoupled from primitive streak induction.","method":"Tcf7l1 knockout mouse analysis, embryo phenotyping, lineage marker analysis","journal":"Development","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean knockout with defined developmental phenotype, single lab, two orthogonal readouts (mesoderm markers, primitive streak)","pmids":["23487311"],"is_preprint":false},{"year":2015,"finding":"Downstream of GSK3 inhibition, β-catenin reduces Tcf7l1 DNA binding (acting on protein) while elevated cMyc reduces Tcf7l1 mRNA levels; together they de-repress FoxA2, a pioneer factor for endoderm specification. Deletion of Tcf7l1 alone is sufficient to allow FoxA2 upregulation in the presence of Activin.","method":"GSK3 inhibitor treatment, Tcf7l1 knockout ESCs, chromatin immunoprecipitation, qRT-PCR, rescue experiments","journal":"The EMBO Journal","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal approaches (genetic deletion, inhibitor treatment, ChIP, rescue) in a single rigorous study","pmids":["26675138"],"is_preprint":false},{"year":2015,"finding":"Jmjd6 (a JmjC-domain protein) physically interacts with Tcf7l1 at the region responsible for Groucho corepressor binding, displacing Groucho and thereby de-repressing Tcf7l1 transcriptional targets; Jmjd6 antagonizes Tcf7l1 repressor activity and enhances β-catenin-induced gene activation in cells and Xenopus embryos.","method":"Co-immunoprecipitation (pulldown), reporter gene assays, Jmjd6 loss-of-function (morpholino), Xenopus embryo axis/gene-expression analysis","journal":"Journal of Biological Chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP plus functional reporter assays and in vivo loss-of-function, single lab","pmids":["26157142"],"is_preprint":false},{"year":2016,"finding":"TCF7L1 functions as a transcriptional repressor that buffers β-catenin/TCF target gene expression in colorectal cancer; loss of TCF7L1 activates EPHB3 (a tumor suppressor/Paneth cell differentiation marker), and EPHB3 knockdown partially rescues growth of TCF7L1-null HCT116 cells.","method":"TCF7L1 knockdown/knockout in HCT116 CRC cells, mouse xenograft model, EPHB3 knockdown epistasis, colony formation and cell-cycle assays","journal":"Scientific Reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — epistasis (double knockdown rescue), xenograft, multiple cellular assays, single lab","pmids":["27333864"],"is_preprint":false},{"year":2017,"finding":"TCF7L1 promotes skin tumor growth and overrides oncogenic RAS-induced senescence independently of β-catenin interaction, using separation-of-function mutants. LCN2 was identified as a major downstream transcriptional effector of TCF7L1 driving tumor growth.","method":"Separation-of-function mutants (β-catenin-binding domain deleted), TCF7L1 overexpression/knockdown in mouse skin SCC model and xenograft, transcriptome profiling, LCN2 gain/loss-of-function assays","journal":"eLife","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — structure-function mutagenesis combined with in vivo models, transcriptomics, and gain/loss rescue experiments across multiple orthogonal approaches","pmids":["28467300"],"is_preprint":false},{"year":2018,"finding":"Tcf7l1 directly promotes cardiomyocyte differentiation from ESCs in a β-catenin-independent manner; Tcf7l1-VP16 (activation domain fusion) and Tcf7l1dN (lacking β-catenin-binding domain) retain pro-cardiac activity, whereas Tcf7l1-En (repressor fusion) is ineffective.","method":"Temporally controlled Tcf7l1 expression in Tcf7l1-null ESCs, domain-swap fusion constructs (VP16, EnR, dN), cardiomyocyte differentiation assays","journal":"Stem Cell Research & Therapy","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — structure-function mutagenesis with defined phenotypic readout, but single lab and limited replication","pmids":["30326964"],"is_preprint":false},{"year":2019,"finding":"Tcf7l1 transcriptionally represses Nanog in liver cancer stem cells (independently of β-catenin), attenuating their self-renewal. IGF signaling stimulates Tcf7l1 phosphorylation and protein degradation through the MEK/ERK pathway.","method":"Ectopic expression/knockdown in liver CSC populations, ChIP or reporter assays for Nanog repression, IGF pathway inhibition, phosphorylation assays","journal":"Stem Cells","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional gain/loss with defined target (Nanog), pathway-inhibitor dissection of MEK/ERK-driven phosphorylation/degradation, single lab","pmids":["31322782"],"is_preprint":false},{"year":2020,"finding":"β-catenin recruits casein kinase 2 (CK2, specifically Csnk2α1) to phosphorylate Tcf7l1, promoting its protein degradation in mouse ESCs. CK2 inhibition blocks CHIR99021-induced Tcf7l1 reduction; Csnk2α1 physically interacts with Tcf7l1 and this interaction is enhanced by GSK3 inhibition.","method":"CK2 inhibitor treatment (TBB/DMAT), Csnk2 overexpression/knockdown, co-immunoprecipitation of Csnk2α1–Tcf7l1, protein stability assays in mESCs","journal":"Biochemical and Biophysical Research Communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP plus gain/loss-of-function for kinase and pharmacological inhibitor validation, single lab","pmids":["31987502"],"is_preprint":false},{"year":2021,"finding":"TCF7L1 directly binds the regulatory sequences of IL-8 and CXCR2 promoters upon WNT4 activation, upregulating IL-8/CXCR2 signaling to drive neuroendocrine differentiation and cell motility in prostate cancer.","method":"ChIP at IL-8/CXCR2 regulatory regions, TCF7L1 gain/loss-of-function, WNT4 stimulation, cell motility assays","journal":"Oncogenesis","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP-based direct binding evidence plus functional gain/loss readouts, single lab","pmids":["34799554"],"is_preprint":false},{"year":2023,"finding":"TCF7L1 binds and represses naive pluripotency factor genes and formative pluripotency regulators (including Otx2 and Lef1), thereby driving pluripotency exit and primitive endoderm (PE) specification; Tcf7l1 deletion abrogates PE differentiation without restraining epiblast priming.","method":"Time-series RNA sequencing, promoter occupancy (ChIP), Tcf7l1 conditional knockout in mESCs and preimplantation embryos","journal":"Nature Communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — ChIP (promoter occupancy) plus RNA-seq plus genetic knockout in two biological contexts (mESCs and embryos), single lab but multiple orthogonal methods","pmids":["36869101"],"is_preprint":false},{"year":2023,"finding":"RNF2 (an E3 ubiquitin ligase) ubiquitinates TCF7L1 and promotes its degradation upon Wnt signaling activation, destabilizing nuclear TCF7L1 to permit Wnt target gene transcription and controlling the threshold, persistence, and termination of Wnt signaling.","method":"RNF2 loss-of-function, ubiquitination assays, TCF7L1 protein stability measurements, Wnt target gene reporter assays","journal":"Scientific Reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ubiquitination assay plus loss-of-function with gene-expression readouts, single lab","pmids":["37957244"],"is_preprint":false},{"year":2023,"finding":"TCF7L1 binds a promoter-proximal Wnt-responsive element (WRE) at the LGR5 locus via a consensus TCF binding element to repress LGR5 expression; restoring LGR5 rescues TCF7L1-mediated reduction in spheroid formation of CRC cells.","method":"ChIP (TCF7L1 binding at LGR5 WRE), TCF7L1 knockdown/overexpression, CRISPRa/i epigenetic modulation, spheroid formation rescue assays","journal":"Genes","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP-confirmed direct binding plus CRISPR epigenetic modulation and rescue experiment, single lab","pmids":["36833408"],"is_preprint":false},{"year":2023,"finding":"TCF7L1 promotes tuft cell differentiation in the adult small intestine and prevents precocious differentiation of embryonic intestinal progenitors; Tcf7l1 deficiency upregulates Notch effector Rbp-J, causing loss of embryonic secretory progenitors.","method":"Conditional Tcf7l1 knockout mice, intestinal epithelium phenotyping, marker analysis (tuft cell, secretory lineage, Notch pathway targets)","journal":"Cells","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — conditional knockout with defined molecular (Rbp-J upregulation) and cellular phenotypes, single lab","pmids":["37296573"],"is_preprint":false},{"year":2024,"finding":"Tbl1 (Tbl1x) physically interacts with Tcf7l1 and translocates from cytoplasm to nucleus with β-catenin upon GSK3 inhibition, acting as an adaptor to promote Tcf7l1 ubiquitylation and degradation in mESCs, thereby maintaining naïve pluripotency. Tblr1 affects Tcf7l1 levels but does not interact with it directly.","method":"Co-immunoprecipitation (Tbl1–Tcf7l1 interaction), Tbl1/Tblr1 overexpression and knockdown, ubiquitylation assays, subcellular fractionation/nuclear translocation imaging, mESC self-renewal assays","journal":"Journal of Cell Science","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP plus ubiquitylation assay plus localization data with functional readout, single lab","pmids":["38639717"],"is_preprint":false},{"year":2024,"finding":"A chromatin-associated TCF7L1 protein complex in human ESCs was characterized by RIME (rapid immunoprecipitation of endogenous proteins), identifying known and novel chromatin-bound partners of TCF7L1 in primed pluripotent cells.","method":"RIME (endogenous chromatin IP coupled to mass spectrometry) in hESCs","journal":"Proteomics","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single-method interactome screen (RIME), no functional follow-up described in the abstract","pmids":["38629187"],"is_preprint":false},{"year":2024,"finding":"TCF7L1 represses GAS1 expression by binding its genomic locus; TCF7L1-mediated GAS1 repression promotes migration, invasion, and adhesion of colorectal cancer cells.","method":"TCF7L1 silencing/overexpression, genome-wide TCF7L1 ChIP-seq, transcriptome analysis, GAS1 rescue experiments, migration/invasion assays","journal":"Scientific Reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP-seq direct binding evidence plus gain/loss rescue with functional assays, single lab","pmids":["38816533"],"is_preprint":false},{"year":2024,"finding":"TCF7L1-mediated upregulation of HSPB6 suppresses the PI3K/AKT/mTOR signaling pathway in bladder cancer cells, inhibiting proliferation and metastasis.","method":"TCF7L1 overexpression/knockdown, RNA sequencing, western blot for PI3K/AKT/mTOR pathway components, cell proliferation and invasion assays","journal":"Journal of Biological Chemistry","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, indirect pathway readout without direct binding or mutagenesis evidence for the TCF7L1–HSPB6 regulatory link described in abstract","pmids":["39608715"],"is_preprint":false},{"year":2026,"finding":"O-GlcNAcylation of TCF7L1 (promoted by ONX-0914 activation of the hexosamine biosynthetic pathway) stabilizes TCF7L1 protein, which in turn transcriptionally represses androgen receptor (AR) expression to suppress prostate cancer progression.","method":"O-GlcNAcylation assays, protein stability assays, TCF7L1 overexpression in xenograft models, qPCR/western blot for AR and EMT markers","journal":"Oncology Research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — O-GlcNAcylation biochemical assay plus in vivo xenograft plus functional AR repression readout, single lab","pmids":["41930151"],"is_preprint":false},{"year":2017,"finding":"Tcf7l1 promotes transcription of Klf4 in early Xenopus embryos in a β-catenin-independent manner; a dominant-negative form of Tcf7l1 lacking the β-catenin binding motif still activates Klf4 transcription, and cycloheximide treatment showed a direct transcriptional effect.","method":"Tcf7l1 overexpression and dominant-negative mutant (dnTcf7l1) in Xenopus embryos, Klf4 promoter-reporter assay, cycloheximide treatment","journal":"Journal of Biomedical Research","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, reporter assay with dominant-negative mutant in Xenopus, limited mechanistic depth","pmids":["29336356"],"is_preprint":false},{"year":2014,"finding":"Sox4 directly regulates Tcf7l1 transcription (identified by microarray and ChIP); Tcf7l1 is a key downstream effector of Sox4 in BCR-ABL+ ALL, as Tcf7l1 knockdown mimics Sox4 loss and ectopic Tcf7l1 rescues proliferation in Sox4-knockout leukemic cells.","method":"Microarray, ChIP (Sox4 binding at Tcf7l1 locus), Tcf7l1 knockdown, Sox4 knockout with Tcf7l1 ectopic rescue, in vitro and in vivo leukemia progression assays","journal":"Haematologica","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP for direct Sox4–Tcf7l1 regulation plus epistasis rescue, single lab","pmids":["24997151"],"is_preprint":false}],"current_model":"TCF7L1 (formerly TCF3) is a transcriptional repressor that functions as a downstream effector of Wnt/β-catenin signaling: in the absence of Wnt, it recruits Groucho corepressors to silence target genes (including pluripotency factors and lineage-specification genes); upon Wnt activation, β-catenin—aided by adaptor proteins Tbl1 and the E3 ligases RNF2 and CK2—displaces TCF7L1 from DNA and targets it for ubiquitin-proteasome degradation, de-repressing Wnt target genes; TCF7L1 can also act as a β-catenin-independent transactivator in specific contexts (e.g., cardiac differentiation, Klf4 regulation), and its stability is additionally regulated by MEK/ERK-driven phosphorylation (downstream of IGF) and by O-GlcNAcylation, with direct transcriptional targets including FoxA2, Nanog, LGR5, GAS1, EPHB3, LCN2, IL-8/CXCR2, and AR."},"narrative":{"mechanistic_narrative":"TCF7L1 is a sequence-specific HMG-box transcription factor that functions primarily as a Wnt/β-catenin-responsive repressor controlling pluripotency exit, lineage specification, and tumor cell behavior [PMID:23810553, PMID:36869101]. In the absence of Wnt, it occupies TCF binding elements at target promoters and represses transcription; Wnt activation inactivates TCF7L1 chiefly by stripping it from DNA rather than converting it to a coactivator, an event that is necessary and sufficient to account for the TCF7L1–β-catenin interaction in vivo [PMID:23810553]. DNA-displaced TCF7L1 is then destabilized by a convergent set of post-translational mechanisms: β-catenin recruits casein kinase 2 (Csnk2α1) to phosphorylate TCF7L1, the adaptor Tbl1 (Tbl1x) translocates to the nucleus with β-catenin to promote its ubiquitylation, and the E3 ligase RNF2 ubiquitinates TCF7L1 to set the threshold and termination of Wnt signaling [PMID:31987502, PMID:38639717, PMID:37957244]. Independent of β-catenin, TCF7L1 stability is tuned by MEK/ERK-driven phosphorylation downstream of IGF and by O-GlcNAcylation [PMID:31322782, PMID:41930151]. In stem and embryonic cells, TCF7L1 repressor activity restrains naive and formative pluripotency genes (including Otx2 and Lef1) and Nanog to drive pluripotency exit and primitive endoderm specification and to enable timely mesoderm and endoderm commitment, the latter through de-repression of the pioneer factor FoxA2 [PMID:36869101, PMID:26675138, PMID:23487311, PMID:31322782]. TCF7L1 also acts as a β-catenin-independent transactivator in defined settings, promoting cardiomyocyte differentiation and activating Klf4 [PMID:30326964, PMID:29336356]. Across cancers it governs target genes that include the tumor suppressor EPHB3, LCN2, LGR5, GAS1, IL-8/CXCR2, and androgen receptor, with context-dependent pro- and anti-tumor effects [PMID:27333864, PMID:28467300, PMID:36833408, PMID:38816533, PMID:34799554, PMID:41930151].","teleology":[{"year":2013,"claim":"Established the core logic of how β-catenin neutralizes TCF7L1: it was unknown whether β-catenin converts TCF7L1 into an activator or simply inactivates it, and genetics showed inactivation by DNA displacement and degradation is the sole required output.","evidence":"Co-IP, DNA-binding assays, and mouse knockout/knock-in epistasis","pmids":["23810553"],"confidence":"High","gaps":["Did not identify the degradation machinery acting on displaced TCF7L1","Did not resolve which target genes depend on this switch in vivo"]},{"year":2013,"claim":"Defined a developmental requirement for TCF7L1 repressor activity, showing it is needed in pluripotent epiblast for timely lineage specification rather than for primitive streak induction per se.","evidence":"Tcf7l1 knockout mouse embryo phenotyping and lineage marker analysis","pmids":["23487311"],"confidence":"Medium","gaps":["Direct repressed targets driving the mesoderm delay not enumerated","Did not separate repressor versus structural roles"]},{"year":2015,"claim":"Connected Wnt input to a specific endoderm program, showing β-catenin reduces TCF7L1 DNA binding while cMyc lowers its mRNA, jointly de-repressing the pioneer factor FoxA2.","evidence":"GSK3 inhibition, Tcf7l1-null ESCs, ChIP, qRT-PCR, and rescue","pmids":["26675138"],"confidence":"High","gaps":["Relative contribution of protein- versus mRNA-level control unquantified","FoxA2 downstream endoderm program not fully mapped"]},{"year":2015,"claim":"Identified a corepressor-displacement mechanism, showing Jmjd6 binds TCF7L1 at its Groucho-binding region to evict Groucho and de-repress targets.","evidence":"Co-IP, reporter assays, and morpholino loss-of-function in Xenopus","pmids":["26157142"],"confidence":"Medium","gaps":["Whether Jmjd6 enzymatic activity is required is unresolved","Endogenous target genes affected not defined"]},{"year":2014,"claim":"Placed TCF7L1 within a transcriptional hierarchy by identifying Sox4 as a direct upstream activator of TCF7L1 in BCR-ABL+ ALL, with TCF7L1 as a key effector of Sox4-driven proliferation.","evidence":"Microarray, Sox4 ChIP at the Tcf7l1 locus, knockdown, and ectopic-rescue leukemia assays","pmids":["24997151"],"confidence":"Medium","gaps":["TCF7L1 target genes mediating leukemic proliferation not identified","Wnt dependence of this axis untested"]},{"year":2016,"claim":"Showed TCF7L1 buffers β-catenin/TCF output in colorectal cancer, with loss activating the tumor suppressor EPHB3 to limit growth.","evidence":"TCF7L1 knockdown/knockout in HCT116, xenografts, and EPHB3 epistasis rescue","pmids":["27333864"],"confidence":"Medium","gaps":["Direct EPHB3 promoter occupancy not shown here","Partial rescue implies additional effectors"]},{"year":2017,"claim":"Demonstrated a β-catenin-independent oncogenic function, with TCF7L1 overriding RAS-induced senescence in skin tumors via the downstream effector LCN2.","evidence":"Separation-of-function mutants, in vivo SCC/xenograft models, transcriptomics, and LCN2 rescue","pmids":["28467300"],"confidence":"High","gaps":["Whether LCN2 is a direct TCF7L1 target not established","Mechanism of β-catenin-independent regulation unspecified"]},{"year":2018,"claim":"Extended β-catenin-independent activity to differentiation, showing TCF7L1 directly promotes cardiomyocyte fate, with activation-domain fusions retaining and repressor fusions lacking pro-cardiac activity.","evidence":"Temporally controlled expression in Tcf7l1-null ESCs with VP16/EnR/dN domain-swap constructs","pmids":["30326964"],"confidence":"Medium","gaps":["Direct pro-cardiac target genes not identified","Single lab, limited replication"]},{"year":2017,"claim":"Provided early evidence for TCF7L1 as a direct transactivator, activating Klf4 transcription independent of β-catenin binding.","evidence":"Overexpression and dnTcf7l1 mutant in Xenopus, Klf4 reporter, and cycloheximide treatment","pmids":["29336356"],"confidence":"Low","gaps":["Limited mechanistic depth; reporter-based in a single system","Endogenous direct binding at Klf4 not shown"]},{"year":2019,"claim":"Linked TCF7L1 to cancer stem cell self-renewal and revealed an IGF input, showing TCF7L1 represses Nanog and that MEK/ERK phosphorylation drives its degradation.","evidence":"Gain/loss in liver CSCs, Nanog repression assays, IGF pathway inhibition, and phosphorylation assays","pmids":["31322782"],"confidence":"Medium","gaps":["ERK phosphosites on TCF7L1 not mapped","Crosstalk with β-catenin-driven degradation unresolved"]},{"year":2020,"claim":"Identified the kinase coupling β-catenin to TCF7L1 turnover, showing β-catenin recruits CK2 (Csnk2α1) to phosphorylate TCF7L1 and promote its degradation.","evidence":"CK2 inhibitors, Csnk2 gain/loss, reciprocal Co-IP, and protein-stability assays in mESCs","pmids":["31987502"],"confidence":"Medium","gaps":["CK2 target phosphosites not defined","Link to a specific E3 ligase not established here"]},{"year":2023,"claim":"Resolved a degradation adaptor and an E3 ligase: Tbl1 shuttles to the nucleus with β-catenin to promote TCF7L1 ubiquitylation, and RNF2 ubiquitinates TCF7L1 to set Wnt signaling thresholds.","evidence":"Co-IP, ubiquitylation assays, fractionation/imaging, and protein-stability/reporter assays","pmids":["38639717","37957244"],"confidence":"Medium","gaps":["Whether Tbl1, RNF2, and CK2 act in one pathway or in parallel is unresolved","Ubiquitin chain types and lysine targets unspecified"]},{"year":2023,"claim":"Mapped TCF7L1's role in early embryo fate decisions, showing it represses naive/formative pluripotency genes (Otx2, Lef1) to drive pluripotency exit and primitive endoderm specification.","evidence":"Time-series RNA-seq, promoter ChIP, and conditional knockout in mESCs and embryos","pmids":["36869101"],"confidence":"High","gaps":["Cofactors directing PE-specific repression not identified","Relation to FoxA2/endoderm program in other contexts unintegrated"]},{"year":2023,"claim":"Expanded the direct CRC target repertoire and tissue roles, showing TCF7L1 represses LGR5 via a promoter-proximal WRE and controls intestinal tuft/secretory differentiation by restraining Notch effector Rbp-J.","evidence":"ChIP at LGR5 WRE with CRISPRa/i and rescue; conditional knockout mouse intestinal phenotyping","pmids":["36833408","37296573"],"confidence":"Medium","gaps":["Mechanism of Rbp-J repression (direct vs indirect) unclear","How LGR5 repression integrates with stem-cell Wnt output untested"]},{"year":2024,"claim":"Defined additional CRC-relevant direct targets genome-wide, showing TCF7L1 represses GAS1 to promote migration, invasion, and adhesion.","evidence":"TCF7L1 ChIP-seq, transcriptomics, GAS1 rescue, and migration/invasion assays","pmids":["38816533"],"confidence":"Medium","gaps":["Whether GAS1 repression is Wnt-dependent not addressed","Single lab"]},{"year":2024,"claim":"Began cataloguing the chromatin-bound TCF7L1 interactome in human pluripotent cells.","evidence":"RIME endogenous chromatin IP-MS in hESCs","pmids":["38629187"],"confidence":"Low","gaps":["Single-method screen with no functional validation of novel partners","Partner identities not functionally placed in a pathway"]},{"year":2021,"claim":"Showed a context-specific activator role in prostate cancer, with TCF7L1 binding IL-8 and CXCR2 promoters upon WNT4 to drive neuroendocrine differentiation and motility.","evidence":"ChIP at IL-8/CXCR2 regulatory regions, gain/loss, WNT4 stimulation, and motility assays","pmids":["34799554"],"confidence":"Medium","gaps":["What converts TCF7L1 from repressor to activator at these loci unknown","Cofactor dependence undefined"]},{"year":2024,"claim":"Introduced O-GlcNAcylation as a stabilizing modification, with O-GlcNAcylated TCF7L1 repressing androgen receptor to suppress prostate cancer.","evidence":"O-GlcNAcylation and stability assays, xenografts, and AR/EMT marker readouts","pmids":["41930151"],"confidence":"Medium","gaps":["Modified residues not mapped","Whether AR repression is direct not established"]},{"year":null,"claim":"How TCF7L1 switches between repressor and β-catenin-independent activator at specific loci, and how its multiple destabilization inputs (CK2, ERK, Tbl1, RNF2, O-GlcNAc) are integrated, remain unresolved.","evidence":"","pmids":[],"confidence":"Low","gaps":["No unified model linking the post-translational modifiers to specific degradation pathways","Determinants of activator versus repressor mode at individual targets unknown","No structural model of TCF7L1 on DNA with cofactors in the corpus"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140110","term_label":"transcription regulator activity","supporting_discovery_ids":[0,2,10,16,9,5]},{"term_id":"GO:0003677","term_label":"DNA binding","supporting_discovery_ids":[0,12,16,9]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0,14,11]},{"term_id":"GO:0005694","term_label":"chromosome","supporting_discovery_ids":[15,16]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0,2,11]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[10,16,9]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[1,10,6,13]},{"term_id":"R-HSA-1643685","term_label":"Disease","supporting_discovery_ids":[4,5,9,16]}],"complexes":[],"partners":["CTNNB1","CSNK2A1","TBL1X","RNF2","JMJD6","GROUCHO"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9HCS4","full_name":"Transcription factor 7-like 1","aliases":["HMG box transcription factor 3","TCF-3"],"length_aa":588,"mass_kda":62.6,"function":"Participates in the Wnt signaling pathway. Binds to DNA and acts as a repressor in the absence of CTNNB1, and as an activator in its presence. Necessary for the terminal differentiation of epidermal cells, the formation of keratohyalin granules and the development of the barrier function of the epidermis (By similarity). Down-regulates NQO1, leading to increased mitomycin c resistance","subcellular_location":"Nucleus","url":"https://www.uniprot.org/uniprotkb/Q9HCS4/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/TCF7L1","classification":"Not Classified","n_dependent_lines":15,"n_total_lines":1208,"dependency_fraction":0.012417218543046357},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/TCF7L1","total_profiled":1310},"omim":[{"mim_id":"604652","title":"TRANSCRIPTION FACTOR 7-LIKE 1; TCF7L1","url":"https://www.omim.org/entry/604652"},{"mim_id":"602228","title":"TRANSCRIPTION FACTOR 7-LIKE 2; TCF7L2","url":"https://www.omim.org/entry/602228"},{"mim_id":"147141","title":"TRANSCRIPTION FACTOR 3; TCF3","url":"https://www.omim.org/entry/147141"},{"mim_id":"114500","title":"COLORECTAL CANCER; CRC","url":"https://www.omim.org/entry/114500"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoplasm","reliability":"Supported"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/TCF7L1"},"hgnc":{"alias_symbol":[],"prev_symbol":["TCF3"]},"alphafold":{"accession":"Q9HCS4","domains":[{"cath_id":"1.10.30.10","chopping":"348-415","consensus_level":"medium","plddt":92.5981,"start":348,"end":415}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9HCS4","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9HCS4-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9HCS4-F1-predicted_aligned_error_v6.png","plddt_mean":51.78},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=TCF7L1","jax_strain_url":"https://www.jax.org/strain/search?query=TCF7L1"},"sequence":{"accession":"Q9HCS4","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9HCS4.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9HCS4/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9HCS4"}},"corpus_meta":[{"pmid":"23810553","id":"PMC_23810553","title":"Regulation of Tcf7l1 DNA binding and protein stability as principal mechanisms of Wnt/β-catenin signaling.","date":"2013","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/23810553","citation_count":99,"is_preprint":false},{"pmid":"23487311","id":"PMC_23487311","title":"Tcf7l1 prepares epiblast cells in the gastrulating mouse embryo for lineage specification.","date":"2013","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/23487311","citation_count":59,"is_preprint":false},{"pmid":"27333864","id":"PMC_27333864","title":"TCF7L1 Modulates Colorectal Cancer Growth by Inhibiting Expression of the Tumor-Suppressor Gene EPHB3.","date":"2016","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/27333864","citation_count":41,"is_preprint":false},{"pmid":"26675138","id":"PMC_26675138","title":"Convergence of cMyc and β-catenin on Tcf7l1 enables endoderm specification.","date":"2015","source":"The EMBO 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Acts as a Suppressor for the Self-Renewal of Liver Cancer Stem Cells and Is Regulated by IGF/MEK/ERK Signaling Independent of β-Catenin.","date":"2019","source":"Stem cells (Dayton, Ohio)","url":"https://pubmed.ncbi.nlm.nih.gov/31322782","citation_count":14,"is_preprint":false},{"pmid":"26157142","id":"PMC_26157142","title":"JmjC Domain-containing Protein 6 (Jmjd6) Derepresses the Transcriptional Repressor Transcription Factor 7-like 1 (Tcf7l1) and Is Required for Body Axis Patterning during Xenopus Embryogenesis.","date":"2015","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/26157142","citation_count":14,"is_preprint":false},{"pmid":"36908661","id":"PMC_36908661","title":"TCF7L1 Accelerates Smooth Muscle Cell Phenotypic Switching and Aggravates Abdominal Aortic Aneurysms.","date":"2022","source":"JACC. Basic to translational science","url":"https://pubmed.ncbi.nlm.nih.gov/36908661","citation_count":12,"is_preprint":false},{"pmid":"30326964","id":"PMC_30326964","title":"Tcf7l1 directly regulates cardiomyocyte differentiation in embryonic stem cells.","date":"2018","source":"Stem cell research & therapy","url":"https://pubmed.ncbi.nlm.nih.gov/30326964","citation_count":11,"is_preprint":false},{"pmid":"34799554","id":"PMC_34799554","title":"TCF7L1 regulates cytokine response and neuroendocrine differentiation of prostate cancer.","date":"2021","source":"Oncogenesis","url":"https://pubmed.ncbi.nlm.nih.gov/34799554","citation_count":11,"is_preprint":false},{"pmid":"31381875","id":"PMC_31381875","title":"Wnt suppressor and stem cell regulator TCF7L1 is a sensitive immunohistochemical marker to differentiate testicular seminoma from non-seminomatous germ cell tumor.","date":"2019","source":"Experimental and molecular pathology","url":"https://pubmed.ncbi.nlm.nih.gov/31381875","citation_count":10,"is_preprint":false},{"pmid":"21932308","id":"PMC_21932308","title":"Tcf7l1 is required for spinal cord progenitor maintenance.","date":"2011","source":"Developmental dynamics : an official publication of the American Association of Anatomists","url":"https://pubmed.ncbi.nlm.nih.gov/21932308","citation_count":10,"is_preprint":false},{"pmid":"23707897","id":"PMC_23707897","title":"Tcf7l1 proteins cell autonomously restrict cardiomyocyte and promote endothelial specification in zebrafish.","date":"2013","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/23707897","citation_count":7,"is_preprint":false},{"pmid":"38816533","id":"PMC_38816533","title":"TCF7L1 regulates colorectal cancer cell migration by repressing GAS1 expression.","date":"2024","source":"Scientific 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communications","url":"https://pubmed.ncbi.nlm.nih.gov/31987502","citation_count":4,"is_preprint":false},{"pmid":"39069233","id":"PMC_39069233","title":"miR-10167-3p targets TCF7L1 to inhibit bovine adipocyte differentiation and promote bovine adipocyte proliferation.","date":"2024","source":"Genomics","url":"https://pubmed.ncbi.nlm.nih.gov/39069233","citation_count":4,"is_preprint":false},{"pmid":"37296573","id":"PMC_37296573","title":"TCF7L1 Controls the Differentiation of Tuft Cells in Mouse Small Intestine.","date":"2023","source":"Cells","url":"https://pubmed.ncbi.nlm.nih.gov/37296573","citation_count":2,"is_preprint":false},{"pmid":"37957244","id":"PMC_37957244","title":"RNF2 regulates Wnt/ß-catenin signaling via TCF7L1 destabilization.","date":"2023","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/37957244","citation_count":2,"is_preprint":false},{"pmid":"38629187","id":"PMC_38629187","title":"Characterization of a chromatin-associated TCF7L1 complex in human embryonic stem cells.","date":"2024","source":"Proteomics","url":"https://pubmed.ncbi.nlm.nih.gov/38629187","citation_count":1,"is_preprint":false},{"pmid":"38639717","id":"PMC_38639717","title":"Tbl1 promotes Wnt-β-catenin signaling-induced degradation of the Tcf7l1 protein in mouse embryonic stem cells.","date":"2024","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/38639717","citation_count":1,"is_preprint":false},{"pmid":"40135061","id":"PMC_40135061","title":"Combined targeting of TCF7L1/2, PTEN, CDK6, and BCCIP by microRNA miR-29c-3p is associated with reduced invasion and proliferation of endometriotic cells.","date":"2025","source":"Reproductive medicine and biology","url":"https://pubmed.ncbi.nlm.nih.gov/40135061","citation_count":1,"is_preprint":false},{"pmid":"37000492","id":"PMC_37000492","title":"Protective mechanism of TCF7L1 against retinal photoreceptor cell injury following retinitis pigmentosa based on the GEO database.","date":"2023","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/37000492","citation_count":1,"is_preprint":false},{"pmid":"29336356","id":"PMC_29336356","title":"Tcf7l1 promotes transcription of Kruppel-likefactor 4 during Xenopus embryogenesis.","date":"2017","source":"Journal of biomedical research","url":"https://pubmed.ncbi.nlm.nih.gov/29336356","citation_count":1,"is_preprint":false},{"pmid":"41930151","id":"PMC_41930151","title":"ONX-0914 Suppresses Hormone-Sensitive Prostate Cancer by Promoting O-GlcNAcylation-Mediated Stabilization of TCF7L1.","date":"2026","source":"Oncology research","url":"https://pubmed.ncbi.nlm.nih.gov/41930151","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":14479,"output_tokens":5197,"usd":0.060696,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":13545,"output_tokens":5304,"usd":0.100163,"stage2_stop_reason":"end_turn"},"total_usd":0.160859,"stage1_batch_id":"msgbatch_017qqVz33Ga63SCDwzb35XPb","stage2_batch_id":"msgbatch_01Scr2Ei9x4HJMiRGxwrmvLK","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2013,\n      \"finding\": \"β-catenin inactivates Tcf7l1 by removing it from DNA (rather than switching it to a coactivator complex), which leads to Tcf7l1 protein degradation. Mouse genetic experiments demonstrated that Tcf7l1 inactivation is the only required effect of the Tcf7l1–β-catenin interaction.\",\n      \"method\": \"Co-immunoprecipitation, DNA-binding assays, mouse genetic (knockout/knock-in) epistasis experiments\",\n      \"journal\": \"Cell Reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal functional genetics plus DNA-binding assays; multiple orthogonal methods; independently interpreted alongside other labs' work\",\n      \"pmids\": [\"23810553\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Tcf7l1 repressor activity is necessary in pluripotent epiblast cells for rapid lineage specification during gastrulation; Tcf7l1−/− embryos show delayed mesoderm specification uncoupled from primitive streak induction.\",\n      \"method\": \"Tcf7l1 knockout mouse analysis, embryo phenotyping, lineage marker analysis\",\n      \"journal\": \"Development\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean knockout with defined developmental phenotype, single lab, two orthogonal readouts (mesoderm markers, primitive streak)\",\n      \"pmids\": [\"23487311\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"Downstream of GSK3 inhibition, β-catenin reduces Tcf7l1 DNA binding (acting on protein) while elevated cMyc reduces Tcf7l1 mRNA levels; together they de-repress FoxA2, a pioneer factor for endoderm specification. Deletion of Tcf7l1 alone is sufficient to allow FoxA2 upregulation in the presence of Activin.\",\n      \"method\": \"GSK3 inhibitor treatment, Tcf7l1 knockout ESCs, chromatin immunoprecipitation, qRT-PCR, rescue experiments\",\n      \"journal\": \"The EMBO Journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal approaches (genetic deletion, inhibitor treatment, ChIP, rescue) in a single rigorous study\",\n      \"pmids\": [\"26675138\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"Jmjd6 (a JmjC-domain protein) physically interacts with Tcf7l1 at the region responsible for Groucho corepressor binding, displacing Groucho and thereby de-repressing Tcf7l1 transcriptional targets; Jmjd6 antagonizes Tcf7l1 repressor activity and enhances β-catenin-induced gene activation in cells and Xenopus embryos.\",\n      \"method\": \"Co-immunoprecipitation (pulldown), reporter gene assays, Jmjd6 loss-of-function (morpholino), Xenopus embryo axis/gene-expression analysis\",\n      \"journal\": \"Journal of Biological Chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP plus functional reporter assays and in vivo loss-of-function, single lab\",\n      \"pmids\": [\"26157142\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"TCF7L1 functions as a transcriptional repressor that buffers β-catenin/TCF target gene expression in colorectal cancer; loss of TCF7L1 activates EPHB3 (a tumor suppressor/Paneth cell differentiation marker), and EPHB3 knockdown partially rescues growth of TCF7L1-null HCT116 cells.\",\n      \"method\": \"TCF7L1 knockdown/knockout in HCT116 CRC cells, mouse xenograft model, EPHB3 knockdown epistasis, colony formation and cell-cycle assays\",\n      \"journal\": \"Scientific Reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — epistasis (double knockdown rescue), xenograft, multiple cellular assays, single lab\",\n      \"pmids\": [\"27333864\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"TCF7L1 promotes skin tumor growth and overrides oncogenic RAS-induced senescence independently of β-catenin interaction, using separation-of-function mutants. LCN2 was identified as a major downstream transcriptional effector of TCF7L1 driving tumor growth.\",\n      \"method\": \"Separation-of-function mutants (β-catenin-binding domain deleted), TCF7L1 overexpression/knockdown in mouse skin SCC model and xenograft, transcriptome profiling, LCN2 gain/loss-of-function assays\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — structure-function mutagenesis combined with in vivo models, transcriptomics, and gain/loss rescue experiments across multiple orthogonal approaches\",\n      \"pmids\": [\"28467300\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Tcf7l1 directly promotes cardiomyocyte differentiation from ESCs in a β-catenin-independent manner; Tcf7l1-VP16 (activation domain fusion) and Tcf7l1dN (lacking β-catenin-binding domain) retain pro-cardiac activity, whereas Tcf7l1-En (repressor fusion) is ineffective.\",\n      \"method\": \"Temporally controlled Tcf7l1 expression in Tcf7l1-null ESCs, domain-swap fusion constructs (VP16, EnR, dN), cardiomyocyte differentiation assays\",\n      \"journal\": \"Stem Cell Research & Therapy\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — structure-function mutagenesis with defined phenotypic readout, but single lab and limited replication\",\n      \"pmids\": [\"30326964\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Tcf7l1 transcriptionally represses Nanog in liver cancer stem cells (independently of β-catenin), attenuating their self-renewal. IGF signaling stimulates Tcf7l1 phosphorylation and protein degradation through the MEK/ERK pathway.\",\n      \"method\": \"Ectopic expression/knockdown in liver CSC populations, ChIP or reporter assays for Nanog repression, IGF pathway inhibition, phosphorylation assays\",\n      \"journal\": \"Stem Cells\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional gain/loss with defined target (Nanog), pathway-inhibitor dissection of MEK/ERK-driven phosphorylation/degradation, single lab\",\n      \"pmids\": [\"31322782\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"β-catenin recruits casein kinase 2 (CK2, specifically Csnk2α1) to phosphorylate Tcf7l1, promoting its protein degradation in mouse ESCs. CK2 inhibition blocks CHIR99021-induced Tcf7l1 reduction; Csnk2α1 physically interacts with Tcf7l1 and this interaction is enhanced by GSK3 inhibition.\",\n      \"method\": \"CK2 inhibitor treatment (TBB/DMAT), Csnk2 overexpression/knockdown, co-immunoprecipitation of Csnk2α1–Tcf7l1, protein stability assays in mESCs\",\n      \"journal\": \"Biochemical and Biophysical Research Communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP plus gain/loss-of-function for kinase and pharmacological inhibitor validation, single lab\",\n      \"pmids\": [\"31987502\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"TCF7L1 directly binds the regulatory sequences of IL-8 and CXCR2 promoters upon WNT4 activation, upregulating IL-8/CXCR2 signaling to drive neuroendocrine differentiation and cell motility in prostate cancer.\",\n      \"method\": \"ChIP at IL-8/CXCR2 regulatory regions, TCF7L1 gain/loss-of-function, WNT4 stimulation, cell motility assays\",\n      \"journal\": \"Oncogenesis\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP-based direct binding evidence plus functional gain/loss readouts, single lab\",\n      \"pmids\": [\"34799554\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"TCF7L1 binds and represses naive pluripotency factor genes and formative pluripotency regulators (including Otx2 and Lef1), thereby driving pluripotency exit and primitive endoderm (PE) specification; Tcf7l1 deletion abrogates PE differentiation without restraining epiblast priming.\",\n      \"method\": \"Time-series RNA sequencing, promoter occupancy (ChIP), Tcf7l1 conditional knockout in mESCs and preimplantation embryos\",\n      \"journal\": \"Nature Communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — ChIP (promoter occupancy) plus RNA-seq plus genetic knockout in two biological contexts (mESCs and embryos), single lab but multiple orthogonal methods\",\n      \"pmids\": [\"36869101\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"RNF2 (an E3 ubiquitin ligase) ubiquitinates TCF7L1 and promotes its degradation upon Wnt signaling activation, destabilizing nuclear TCF7L1 to permit Wnt target gene transcription and controlling the threshold, persistence, and termination of Wnt signaling.\",\n      \"method\": \"RNF2 loss-of-function, ubiquitination assays, TCF7L1 protein stability measurements, Wnt target gene reporter assays\",\n      \"journal\": \"Scientific Reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ubiquitination assay plus loss-of-function with gene-expression readouts, single lab\",\n      \"pmids\": [\"37957244\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"TCF7L1 binds a promoter-proximal Wnt-responsive element (WRE) at the LGR5 locus via a consensus TCF binding element to repress LGR5 expression; restoring LGR5 rescues TCF7L1-mediated reduction in spheroid formation of CRC cells.\",\n      \"method\": \"ChIP (TCF7L1 binding at LGR5 WRE), TCF7L1 knockdown/overexpression, CRISPRa/i epigenetic modulation, spheroid formation rescue assays\",\n      \"journal\": \"Genes\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP-confirmed direct binding plus CRISPR epigenetic modulation and rescue experiment, single lab\",\n      \"pmids\": [\"36833408\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"TCF7L1 promotes tuft cell differentiation in the adult small intestine and prevents precocious differentiation of embryonic intestinal progenitors; Tcf7l1 deficiency upregulates Notch effector Rbp-J, causing loss of embryonic secretory progenitors.\",\n      \"method\": \"Conditional Tcf7l1 knockout mice, intestinal epithelium phenotyping, marker analysis (tuft cell, secretory lineage, Notch pathway targets)\",\n      \"journal\": \"Cells\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — conditional knockout with defined molecular (Rbp-J upregulation) and cellular phenotypes, single lab\",\n      \"pmids\": [\"37296573\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Tbl1 (Tbl1x) physically interacts with Tcf7l1 and translocates from cytoplasm to nucleus with β-catenin upon GSK3 inhibition, acting as an adaptor to promote Tcf7l1 ubiquitylation and degradation in mESCs, thereby maintaining naïve pluripotency. Tblr1 affects Tcf7l1 levels but does not interact with it directly.\",\n      \"method\": \"Co-immunoprecipitation (Tbl1–Tcf7l1 interaction), Tbl1/Tblr1 overexpression and knockdown, ubiquitylation assays, subcellular fractionation/nuclear translocation imaging, mESC self-renewal assays\",\n      \"journal\": \"Journal of Cell Science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP plus ubiquitylation assay plus localization data with functional readout, single lab\",\n      \"pmids\": [\"38639717\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"A chromatin-associated TCF7L1 protein complex in human ESCs was characterized by RIME (rapid immunoprecipitation of endogenous proteins), identifying known and novel chromatin-bound partners of TCF7L1 in primed pluripotent cells.\",\n      \"method\": \"RIME (endogenous chromatin IP coupled to mass spectrometry) in hESCs\",\n      \"journal\": \"Proteomics\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single-method interactome screen (RIME), no functional follow-up described in the abstract\",\n      \"pmids\": [\"38629187\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"TCF7L1 represses GAS1 expression by binding its genomic locus; TCF7L1-mediated GAS1 repression promotes migration, invasion, and adhesion of colorectal cancer cells.\",\n      \"method\": \"TCF7L1 silencing/overexpression, genome-wide TCF7L1 ChIP-seq, transcriptome analysis, GAS1 rescue experiments, migration/invasion assays\",\n      \"journal\": \"Scientific Reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP-seq direct binding evidence plus gain/loss rescue with functional assays, single lab\",\n      \"pmids\": [\"38816533\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"TCF7L1-mediated upregulation of HSPB6 suppresses the PI3K/AKT/mTOR signaling pathway in bladder cancer cells, inhibiting proliferation and metastasis.\",\n      \"method\": \"TCF7L1 overexpression/knockdown, RNA sequencing, western blot for PI3K/AKT/mTOR pathway components, cell proliferation and invasion assays\",\n      \"journal\": \"Journal of Biological Chemistry\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, indirect pathway readout without direct binding or mutagenesis evidence for the TCF7L1–HSPB6 regulatory link described in abstract\",\n      \"pmids\": [\"39608715\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"O-GlcNAcylation of TCF7L1 (promoted by ONX-0914 activation of the hexosamine biosynthetic pathway) stabilizes TCF7L1 protein, which in turn transcriptionally represses androgen receptor (AR) expression to suppress prostate cancer progression.\",\n      \"method\": \"O-GlcNAcylation assays, protein stability assays, TCF7L1 overexpression in xenograft models, qPCR/western blot for AR and EMT markers\",\n      \"journal\": \"Oncology Research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — O-GlcNAcylation biochemical assay plus in vivo xenograft plus functional AR repression readout, single lab\",\n      \"pmids\": [\"41930151\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Tcf7l1 promotes transcription of Klf4 in early Xenopus embryos in a β-catenin-independent manner; a dominant-negative form of Tcf7l1 lacking the β-catenin binding motif still activates Klf4 transcription, and cycloheximide treatment showed a direct transcriptional effect.\",\n      \"method\": \"Tcf7l1 overexpression and dominant-negative mutant (dnTcf7l1) in Xenopus embryos, Klf4 promoter-reporter assay, cycloheximide treatment\",\n      \"journal\": \"Journal of Biomedical Research\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, reporter assay with dominant-negative mutant in Xenopus, limited mechanistic depth\",\n      \"pmids\": [\"29336356\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Sox4 directly regulates Tcf7l1 transcription (identified by microarray and ChIP); Tcf7l1 is a key downstream effector of Sox4 in BCR-ABL+ ALL, as Tcf7l1 knockdown mimics Sox4 loss and ectopic Tcf7l1 rescues proliferation in Sox4-knockout leukemic cells.\",\n      \"method\": \"Microarray, ChIP (Sox4 binding at Tcf7l1 locus), Tcf7l1 knockdown, Sox4 knockout with Tcf7l1 ectopic rescue, in vitro and in vivo leukemia progression assays\",\n      \"journal\": \"Haematologica\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP for direct Sox4–Tcf7l1 regulation plus epistasis rescue, single lab\",\n      \"pmids\": [\"24997151\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"TCF7L1 (formerly TCF3) is a transcriptional repressor that functions as a downstream effector of Wnt/β-catenin signaling: in the absence of Wnt, it recruits Groucho corepressors to silence target genes (including pluripotency factors and lineage-specification genes); upon Wnt activation, β-catenin—aided by adaptor proteins Tbl1 and the E3 ligases RNF2 and CK2—displaces TCF7L1 from DNA and targets it for ubiquitin-proteasome degradation, de-repressing Wnt target genes; TCF7L1 can also act as a β-catenin-independent transactivator in specific contexts (e.g., cardiac differentiation, Klf4 regulation), and its stability is additionally regulated by MEK/ERK-driven phosphorylation (downstream of IGF) and by O-GlcNAcylation, with direct transcriptional targets including FoxA2, Nanog, LGR5, GAS1, EPHB3, LCN2, IL-8/CXCR2, and AR.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"TCF7L1 is a sequence-specific HMG-box transcription factor that functions primarily as a Wnt/β-catenin-responsive repressor controlling pluripotency exit, lineage specification, and tumor cell behavior [#0, #10]. In the absence of Wnt, it occupies TCF binding elements at target promoters and represses transcription; Wnt activation inactivates TCF7L1 chiefly by stripping it from DNA rather than converting it to a coactivator, an event that is necessary and sufficient to account for the TCF7L1–β-catenin interaction in vivo [#0]. DNA-displaced TCF7L1 is then destabilized by a convergent set of post-translational mechanisms: β-catenin recruits casein kinase 2 (Csnk2α1) to phosphorylate TCF7L1, the adaptor Tbl1 (Tbl1x) translocates to the nucleus with β-catenin to promote its ubiquitylation, and the E3 ligase RNF2 ubiquitinates TCF7L1 to set the threshold and termination of Wnt signaling [#8, #14, #11]. Independent of β-catenin, TCF7L1 stability is tuned by MEK/ERK-driven phosphorylation downstream of IGF and by O-GlcNAcylation [#7, #18]. In stem and embryonic cells, TCF7L1 repressor activity restrains naive and formative pluripotency genes (including Otx2 and Lef1) and Nanog to drive pluripotency exit and primitive endoderm specification and to enable timely mesoderm and endoderm commitment, the latter through de-repression of the pioneer factor FoxA2 [#10, #2, #1, #7]. TCF7L1 also acts as a β-catenin-independent transactivator in defined settings, promoting cardiomyocyte differentiation and activating Klf4 [#6, #19]. Across cancers it governs target genes that include the tumor suppressor EPHB3, LCN2, LGR5, GAS1, IL-8/CXCR2, and androgen receptor, with context-dependent pro- and anti-tumor effects [#4, #5, #12, #16, #9, #18].\",\n  \"teleology\": [\n    {\n      \"year\": 2013,\n      \"claim\": \"Established the core logic of how β-catenin neutralizes TCF7L1: it was unknown whether β-catenin converts TCF7L1 into an activator or simply inactivates it, and genetics showed inactivation by DNA displacement and degradation is the sole required output.\",\n      \"evidence\": \"Co-IP, DNA-binding assays, and mouse knockout/knock-in epistasis\",\n      \"pmids\": [\"23810553\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not identify the degradation machinery acting on displaced TCF7L1\", \"Did not resolve which target genes depend on this switch in vivo\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Defined a developmental requirement for TCF7L1 repressor activity, showing it is needed in pluripotent epiblast for timely lineage specification rather than for primitive streak induction per se.\",\n      \"evidence\": \"Tcf7l1 knockout mouse embryo phenotyping and lineage marker analysis\",\n      \"pmids\": [\"23487311\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct repressed targets driving the mesoderm delay not enumerated\", \"Did not separate repressor versus structural roles\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Connected Wnt input to a specific endoderm program, showing β-catenin reduces TCF7L1 DNA binding while cMyc lowers its mRNA, jointly de-repressing the pioneer factor FoxA2.\",\n      \"evidence\": \"GSK3 inhibition, Tcf7l1-null ESCs, ChIP, qRT-PCR, and rescue\",\n      \"pmids\": [\"26675138\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Relative contribution of protein- versus mRNA-level control unquantified\", \"FoxA2 downstream endoderm program not fully mapped\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Identified a corepressor-displacement mechanism, showing Jmjd6 binds TCF7L1 at its Groucho-binding region to evict Groucho and de-repress targets.\",\n      \"evidence\": \"Co-IP, reporter assays, and morpholino loss-of-function in Xenopus\",\n      \"pmids\": [\"26157142\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether Jmjd6 enzymatic activity is required is unresolved\", \"Endogenous target genes affected not defined\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Placed TCF7L1 within a transcriptional hierarchy by identifying Sox4 as a direct upstream activator of TCF7L1 in BCR-ABL+ ALL, with TCF7L1 as a key effector of Sox4-driven proliferation.\",\n      \"evidence\": \"Microarray, Sox4 ChIP at the Tcf7l1 locus, knockdown, and ectopic-rescue leukemia assays\",\n      \"pmids\": [\"24997151\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"TCF7L1 target genes mediating leukemic proliferation not identified\", \"Wnt dependence of this axis untested\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Showed TCF7L1 buffers β-catenin/TCF output in colorectal cancer, with loss activating the tumor suppressor EPHB3 to limit growth.\",\n      \"evidence\": \"TCF7L1 knockdown/knockout in HCT116, xenografts, and EPHB3 epistasis rescue\",\n      \"pmids\": [\"27333864\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct EPHB3 promoter occupancy not shown here\", \"Partial rescue implies additional effectors\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Demonstrated a β-catenin-independent oncogenic function, with TCF7L1 overriding RAS-induced senescence in skin tumors via the downstream effector LCN2.\",\n      \"evidence\": \"Separation-of-function mutants, in vivo SCC/xenograft models, transcriptomics, and LCN2 rescue\",\n      \"pmids\": [\"28467300\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether LCN2 is a direct TCF7L1 target not established\", \"Mechanism of β-catenin-independent regulation unspecified\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Extended β-catenin-independent activity to differentiation, showing TCF7L1 directly promotes cardiomyocyte fate, with activation-domain fusions retaining and repressor fusions lacking pro-cardiac activity.\",\n      \"evidence\": \"Temporally controlled expression in Tcf7l1-null ESCs with VP16/EnR/dN domain-swap constructs\",\n      \"pmids\": [\"30326964\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct pro-cardiac target genes not identified\", \"Single lab, limited replication\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Provided early evidence for TCF7L1 as a direct transactivator, activating Klf4 transcription independent of β-catenin binding.\",\n      \"evidence\": \"Overexpression and dnTcf7l1 mutant in Xenopus, Klf4 reporter, and cycloheximide treatment\",\n      \"pmids\": [\"29336356\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Limited mechanistic depth; reporter-based in a single system\", \"Endogenous direct binding at Klf4 not shown\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Linked TCF7L1 to cancer stem cell self-renewal and revealed an IGF input, showing TCF7L1 represses Nanog and that MEK/ERK phosphorylation drives its degradation.\",\n      \"evidence\": \"Gain/loss in liver CSCs, Nanog repression assays, IGF pathway inhibition, and phosphorylation assays\",\n      \"pmids\": [\"31322782\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"ERK phosphosites on TCF7L1 not mapped\", \"Crosstalk with β-catenin-driven degradation unresolved\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Identified the kinase coupling β-catenin to TCF7L1 turnover, showing β-catenin recruits CK2 (Csnk2α1) to phosphorylate TCF7L1 and promote its degradation.\",\n      \"evidence\": \"CK2 inhibitors, Csnk2 gain/loss, reciprocal Co-IP, and protein-stability assays in mESCs\",\n      \"pmids\": [\"31987502\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"CK2 target phosphosites not defined\", \"Link to a specific E3 ligase not established here\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Resolved a degradation adaptor and an E3 ligase: Tbl1 shuttles to the nucleus with β-catenin to promote TCF7L1 ubiquitylation, and RNF2 ubiquitinates TCF7L1 to set Wnt signaling thresholds.\",\n      \"evidence\": \"Co-IP, ubiquitylation assays, fractionation/imaging, and protein-stability/reporter assays\",\n      \"pmids\": [\"38639717\", \"37957244\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether Tbl1, RNF2, and CK2 act in one pathway or in parallel is unresolved\", \"Ubiquitin chain types and lysine targets unspecified\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Mapped TCF7L1's role in early embryo fate decisions, showing it represses naive/formative pluripotency genes (Otx2, Lef1) to drive pluripotency exit and primitive endoderm specification.\",\n      \"evidence\": \"Time-series RNA-seq, promoter ChIP, and conditional knockout in mESCs and embryos\",\n      \"pmids\": [\"36869101\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Cofactors directing PE-specific repression not identified\", \"Relation to FoxA2/endoderm program in other contexts unintegrated\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Expanded the direct CRC target repertoire and tissue roles, showing TCF7L1 represses LGR5 via a promoter-proximal WRE and controls intestinal tuft/secretory differentiation by restraining Notch effector Rbp-J.\",\n      \"evidence\": \"ChIP at LGR5 WRE with CRISPRa/i and rescue; conditional knockout mouse intestinal phenotyping\",\n      \"pmids\": [\"36833408\", \"37296573\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of Rbp-J repression (direct vs indirect) unclear\", \"How LGR5 repression integrates with stem-cell Wnt output untested\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Defined additional CRC-relevant direct targets genome-wide, showing TCF7L1 represses GAS1 to promote migration, invasion, and adhesion.\",\n      \"evidence\": \"TCF7L1 ChIP-seq, transcriptomics, GAS1 rescue, and migration/invasion assays\",\n      \"pmids\": [\"38816533\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether GAS1 repression is Wnt-dependent not addressed\", \"Single lab\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Began cataloguing the chromatin-bound TCF7L1 interactome in human pluripotent cells.\",\n      \"evidence\": \"RIME endogenous chromatin IP-MS in hESCs\",\n      \"pmids\": [\"38629187\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Single-method screen with no functional validation of novel partners\", \"Partner identities not functionally placed in a pathway\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Showed a context-specific activator role in prostate cancer, with TCF7L1 binding IL-8 and CXCR2 promoters upon WNT4 to drive neuroendocrine differentiation and motility.\",\n      \"evidence\": \"ChIP at IL-8/CXCR2 regulatory regions, gain/loss, WNT4 stimulation, and motility assays\",\n      \"pmids\": [\"34799554\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"What converts TCF7L1 from repressor to activator at these loci unknown\", \"Cofactor dependence undefined\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Introduced O-GlcNAcylation as a stabilizing modification, with O-GlcNAcylated TCF7L1 repressing androgen receptor to suppress prostate cancer.\",\n      \"evidence\": \"O-GlcNAcylation and stability assays, xenografts, and AR/EMT marker readouts\",\n      \"pmids\": [\"41930151\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Modified residues not mapped\", \"Whether AR repression is direct not established\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How TCF7L1 switches between repressor and β-catenin-independent activator at specific loci, and how its multiple destabilization inputs (CK2, ERK, Tbl1, RNF2, O-GlcNAc) are integrated, remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No unified model linking the post-translational modifiers to specific degradation pathways\", \"Determinants of activator versus repressor mode at individual targets unknown\", \"No structural model of TCF7L1 on DNA with cofactors in the corpus\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140110\", \"supporting_discovery_ids\": [0, 2, 10, 16, 9, 5]},\n      {\"term_id\": \"GO:0003677\", \"supporting_discovery_ids\": [0, 12, 16, 9]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0, 14, 11]},\n      {\"term_id\": \"GO:0005694\", \"supporting_discovery_ids\": [15, 16]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 2, 11]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [10, 16, 9]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [1, 10, 6, 13]},\n      {\"term_id\": \"R-HSA-1643685\", \"supporting_discovery_ids\": [4, 5, 9, 16]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"CTNNB1\", \"Csnk2a1\", \"Tbl1x\", \"RNF2\", \"Jmjd6\", \"Groucho\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}