{"gene":"TTF2","run_date":"2026-06-10T10:51:56","timeline":{"discoveries":[{"year":1997,"finding":"TTF-2 (mouse) is a forkhead domain-containing DNA-binding protein that recognizes sites on both thyroglobulin (Tg) and thyroperoxidase (TPO) promoters; its expression is transiently downregulated in the developing thyroid just before onset of Tg and TPO gene expression, suggesting a role as a negative controller of thyroid-specific gene expression during development.","method":"cDNA cloning, DNA-binding assays, in situ hybridization/expression analysis in developing mouse thyroid","journal":"The EMBO journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — DNA binding demonstrated directly, temporal expression pattern correlated with functional hypothesis, single lab with two orthogonal methods","pmids":["9214635"],"is_preprint":false},{"year":1997,"finding":"TTF-2 mRNA levels are transcriptionally upregulated by TSH (via cAMP/forskolin), insulin, and IGF-I in FRTL-5 thyroid cells in a dose- and time-dependent manner requiring ongoing protein synthesis, positioning TTF-2 as a mediator of hormonal transcriptional activation of thyroid-specific genes.","method":"Northern blot, nuclear run-off transcription assay, pharmacological treatment of FRTL-5 cells","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — run-off assays confirm transcriptional regulation, two orthogonal methods, single lab","pmids":["9287345"],"is_preprint":false},{"year":1998,"finding":"A missense mutation (Ala65Val) within the forkhead domain of human TTF-2 (FKHL15/FOXE1) causes impaired DNA binding and loss of transcriptional function, establishing that DNA-binding activity of the forkhead domain is required for TTF-2's role in thyroid and palate development.","method":"Homozygosity mapping, direct sequencing, DNA-binding assay, transcriptional reporter assay with mutant protein","journal":"Nature genetics","confidence":"High","confidence_rationale":"Tier 1 / Strong — mutagenesis with functional validation (DNA binding + transcription assay), replicated by subsequent independent mutation studies","pmids":["9697705"],"is_preprint":false},{"year":1999,"finding":"TTF-2 physically interacts with CTF/NF-1 proteins (specifically CTF/NF1-C, which is itself hormonally regulated by TSH/cAMP/insulin) at the TPO promoter; this interaction is required for efficient hormonal regulation of TPO gene expression, and spacing between their binding sites is critical for promoter activity.","method":"GST pull-down assay, transfection/reporter assays, protein-DNA interaction (EMSA), spacing mutagenesis","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — GST pull-down establishing direct interaction, mutagenesis of binding sites, transcriptional reporter assays, multiple orthogonal methods in one study","pmids":["10329730"],"is_preprint":false},{"year":2000,"finding":"TTF-2 acts as a promoter-specific, DNA-binding-independent transcriptional repressor of TTF-1 and Pax-8 activity; the minimal repressor domain functions as an independent domain and repression occurs without TTF-2 binding DNA, suggesting it interferes with a specific cofactor required for TTF-1 and Pax-8 activity.","method":"Transcriptional reporter assays, domain deletion/mutagenesis analysis, co-transfection experiments","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — functional domain mapping with mutagenesis and reporter assays, single lab","pmids":["10944465"],"is_preprint":false},{"year":2002,"finding":"A second missense mutation in the forkhead domain of TTF-2 (S57N) causes impaired DNA binding and partial loss of transcriptional function, confirming that the forkhead domain mediates DNA binding necessary for TTF-2 function in thyroid and palate development.","method":"Direct sequencing, DNA-binding assay, transcriptional reporter assay with mutant protein","journal":"Human molecular genetics","confidence":"High","confidence_rationale":"Tier 1 / Strong — independent replication of mechanism (DNA binding + transcription) established by a second mutation in the same domain across independent labs","pmids":["12165566"],"is_preprint":false},{"year":2003,"finding":"HuF2 (TTF2/hLodestar), a SNF2-family ATPase, interacts with the pre-mRNA splicing factor CDC5L in yeast two-hybrid and HeLa nuclear extract, associates with human splicing complexes, and a truncated HuF2 polypeptide overlapping the CDC5L-binding region inhibits pre-mRNA splicing by disrupting spliceosome assembly.","method":"Yeast two-hybrid, co-immunoprecipitation from HeLa nuclear extract, in vitro splicing inhibition assay, spliceosome assembly assay","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal interaction shown in two systems plus functional splicing inhibition, single lab","pmids":["12927788"],"is_preprint":false},{"year":2004,"finding":"TTF2 (human SNF2-family ATPase) is an RNA polymerase II termination factor responsible for mitotic repression of transcription elongation; siRNA-mediated knockdown of TTF2 causes retention of RNA polymerase II on condensed mitotic chromosomes, and this phenotype is rescued by expression of an siRNA-resistant GFP-TTF2 replacement vector, proving TTF2 is directly responsible.","method":"siRNA knockdown, rescue experiment with siRNA-resistant GFP-TTF2 replacement vector, immunofluorescence microscopy of mitotic chromosomes","journal":"Cell cycle (Georgetown, Tex.)","confidence":"High","confidence_rationale":"Tier 2 / Strong — knockdown phenotype rescued by siRNA-resistant construct, rigorous genetic epistasis, published peer-reviewed study","pmids":["15467445"],"is_preprint":false},{"year":2006,"finding":"A third missense mutation (R102C) within the forkhead DNA-binding domain of TTF-2 causes complete loss of DNA binding and transcriptional inactivity, further confirming the forkhead domain as the essential functional domain for DNA binding.","method":"Direct sequencing, DNA-binding assay, transcriptional reporter assay with mutant protein","journal":"The Journal of clinical endocrinology and metabolism","confidence":"High","confidence_rationale":"Tier 1 / Strong — independent third mutation confirming same mechanism, replicated across multiple labs","pmids":["16882747"],"is_preprint":false},{"year":2024,"finding":"TTF2 (SWI/SNF ATPase) promotes replisome disassembly at stalled replication forks in mitosis by tethering the TRAIP E3 ubiquitin ligase to the CMG helicase via: (1) an N-terminal Zinc finger domain binding phosphorylated TRAIP (phosphorylation by mitotic Cyclin B-CDK1), and (2) an adjacent TTF2 peptide contacting CMG-associated DNA polymerase ε (Polε/POLE2). This TRAIP-TTF2-Polε bridge is independent of TTF2 ATPase activity and is essential for CMG unloading and stalled fork cleavage. In contrast, RNAPII eviction from mitotic chromosomes requires TTF2 ATPase activity.","method":"Xenopus egg extract replisome disassembly assay, domain mutagenesis, phosphorylation analysis, co-immunoprecipitation, biochemical reconstitution","journal":"bioRxiv","confidence":"High","confidence_rationale":"Tier 1 / Strong — reconstitution in Xenopus system, domain mutagenesis, multiple orthogonal biochemical methods, independently replicated by two concurrent preprints","pmids":["39651145"],"is_preprint":true},{"year":2024,"finding":"TTF2 couples the TRAIP ubiquitin ligase to DNA Polymerase ε (Polε) via tandem Zinc fingers recognizing phosphorylated TRAIP and a motif binding POLE2, causing TRAIP to ubiquitylate CMG helicase to trigger replisome disassembly and Mitotic DNA Synthesis (MiDAS); TTF2 ATPase activity is separately required for RNA Pol II removal from mitotic chromosomes.","method":"Biochemical reconstitution, co-immunoprecipitation, domain mutagenesis, ubiquitylation assay, MiDAS assay","journal":"bioRxiv","confidence":"High","confidence_rationale":"Tier 1 / Strong — independent replication of TTF2-TRAIP-Polε mechanism by a second lab using orthogonal methods","pmids":["bio_10.1101_2024.12.01.626218"],"is_preprint":true},{"year":2025,"finding":"TTF2 protein levels oscillate during the cell cycle (high in S and G2/M, low in late mitosis and G1); TTF2 is ubiquitinated by APC/C-CDH1 and degraded via the proteasome; TTF2 binds CDC20 and prevents mitotic checkpoint complex (MCC) formation during normal mitosis; when TTF2 is degraded by APC/C-CDH1 upon persistent G2/M arrest, CDC20 is released to promote MCC assembly.","method":"Cell cycle synchronization/flow cytometry, co-immunoprecipitation, ubiquitination assay, siRNA knockdown/overexpression with cell cycle phenotype readout, proteasome inhibitor treatment","journal":"Science China. Life sciences","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods (Co-IP, ubiquitination assay, genetic perturbation), single lab, not yet independently replicated","pmids":["40410652"],"is_preprint":false},{"year":2025,"finding":"TTF2 contains an NPF motif that binds to the non-catalytic POLE2 subunit of DNA polymerase ε with micromolar affinity; mutation of this NPF motif abolishes binding in cell extracts.","method":"Native holdup assay (quantitative peptide affinity), mutational analysis, proteome-scale affinity screen, AlphaFold structural prediction","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — quantitative binding assay with mutagenesis confirmation, single lab, preprint, consistent with independent structural prediction","pmids":["bio_10.1101_2025.03.17.643635"],"is_preprint":true},{"year":1998,"finding":"TTF-2 DNA-binding activity is detectable in unstimulated dog thyrocytes and increases with forskolin treatment, but mutation of the TTF-2 binding site in the thyroglobulin promoter leaves cAMP-dependent activity largely intact, indicating TTF-2 does NOT play a dominant role in cAMP-dependent control of thyroglobulin gene transcription in primary dog thyrocytes (negative finding).","method":"Nuclear extract binding assay with radiolabeled probe, transient transfection reporter assay with site-directed mutagenesis of TTF-2 binding site","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — two orthogonal methods, but a negative/contradictory result relative to FRTL-5 cell findings; single lab","pmids":["9446794"],"is_preprint":false}],"current_model":"TTF2 is a multifunctional protein with two distinct molecular identities: (1) as FOXE1/TTF-2, a forkhead-domain transcription factor that binds thyroid gene promoters (Tg, TPO) via its forkhead domain, acts as a DNA-binding-independent repressor of TTF-1/Pax-8, physically interacts with CTF/NF-1 for hormonal regulation of TPO, and is regulated transcriptionally by TSH/cAMP and insulin; and (2) as HuF2/TTF2, a SNF2-family ATPase that uses its ATPase activity to evict RNA polymerase II from mitotic chromosomes, interacts with the splicing factor CDC5L to participate in pre-mRNA splicing, and—through an ATPase-independent mechanism—bridges the TRAIP E3 ubiquitin ligase to DNA polymerase ε (POLE2) via an N-terminal Zinc finger recognizing CDK1-phosphorylated TRAIP and an NPF motif binding POLE2, thereby directing CMG helicase ubiquitylation and replisome disassembly at stalled forks in mitosis; additionally, TTF2 protein oscillates through the cell cycle, is degraded by APC/C-CDH1, and regulates mitotic checkpoint complex assembly by sequestering CDC20."},"narrative":{"mechanistic_narrative":"The TTF2 timeline describes two distinct proteins under colliding symbols, and the on-target gene for this entry is the human SNF2-family ATPase TTF2 (HuF2/hLodestar), a cell-cycle-regulated machine that clears chromatin-bound machinery during mitosis [PMID:15467445, PMID:39651145]. TTF2 functions as an RNA polymerase II termination factor that uses its ATPase activity to evict RNA Pol II from condensed mitotic chromosomes; this role is genetically defined, as knockdown causes RNA Pol II retention that is rescued by an siRNA-resistant TTF2 [PMID:15467445]. In an ATPase-independent capacity, TTF2 acts as a molecular bridge that drives replisome disassembly at stalled mitotic replication forks: an N-terminal zinc finger recognizes Cyclin B-CDK1-phosphorylated TRAIP while an adjacent NPF motif binds the non-catalytic POLE2 subunit of DNA polymerase epsilon, tethering the TRAIP E3 ubiquitin ligase to the CMG helicase to direct CMG ubiquitylation, fork cleavage, and mitotic DNA synthesis [PMID:39651145, PMID:bio_10.1101_2024.12.01.626218, PMID:bio_10.1101_2025.03.17.643635]. TTF2 protein oscillates across the cell cycle and is destroyed by APC/C-CDH1, and it also sequesters CDC20 to restrain mitotic checkpoint complex assembly until its degradation releases CDC20 [PMID:40410652]. Separately, TTF2 associates with the spliceosome through the splicing factor CDC5L [PMID:12927788]. The thyroid transcription-factor findings in this corpus ([PMID:9214635]–[PMID:12165566], [PMID:16882747], [PMID:9446794]) describe FOXE1/TTF-2, a different forkhead protein sharing the 'TTF-2' name, and are not part of this gene's mechanism.","teleology":[{"year":2003,"claim":"Established the first molecular partner of the SNF2-family ATPase HuF2/TTF2, linking it to pre-mRNA splicing and indicating a nuclear RNA-processing function.","evidence":"Yeast two-hybrid and Co-IP from HeLa nuclear extract identifying CDC5L interaction, plus a dominant-negative splicing-inhibition assay","pmids":["12927788"],"confidence":"Medium","gaps":["Does not define whether ATPase activity is required for splicing-complex association","Functional role of the CDC5L interaction in normal splicing not resolved beyond a truncation-based inhibition"]},{"year":2004,"claim":"Defined TTF2 as the factor responsible for mitotic transcriptional repression by showing it is required to remove RNA Pol II from condensed chromosomes.","evidence":"siRNA knockdown with siRNA-resistant GFP-TTF2 rescue and immunofluorescence of mitotic chromosomes","pmids":["15467445"],"confidence":"High","gaps":["Did not biochemically separate ATPase-dependent from ATPase-independent activities","Mechanism of Pol II eviction at molecular resolution not established"]},{"year":2024,"claim":"Resolved an ATPase-independent function: TTF2 bridges TRAIP to the replisome to trigger CMG unloading at stalled mitotic forks, separating this activity from its ATPase-dependent Pol II eviction.","evidence":"Xenopus egg extract replisome disassembly reconstitution, domain mutagenesis, phosphorylation analysis, and Co-IP, independently corroborated by a concurrent preprint","pmids":["39651145","bio_10.1101_2024.12.01.626218"],"confidence":"High","gaps":["Both reports are preprints","Structural basis of simultaneous TRAIP and Polε engagement not solved","In vivo consequences of disrupting only the bridge in human cells not detailed"]},{"year":2025,"claim":"Mapped the POLE2-binding determinant to a specific NPF motif, providing the molecular contact point by which TTF2 docks onto DNA polymerase epsilon.","evidence":"Native holdup quantitative affinity assay with NPF-motif mutagenesis and AlphaFold prediction","pmids":["bio_10.1101_2025.03.17.643635"],"confidence":"Medium","gaps":["Single-lab preprint","Micromolar affinity functional relevance in the intact replisome not validated"]},{"year":2025,"claim":"Connected TTF2 abundance to cell-cycle control, showing APC/C-CDH1-driven degradation and CDC20 sequestration that modulates mitotic checkpoint complex assembly.","evidence":"Cell-cycle synchronization, Co-IP, ubiquitination and proteasome-inhibitor assays, and genetic perturbation with cell-cycle readouts","pmids":["40410652"],"confidence":"Medium","gaps":["Single lab, not independently replicated","Whether CDC20 sequestration is direct and how it integrates with the TRAIP/replisome role is unresolved"]},{"year":null,"claim":"How TTF2's two biochemical modes — ATPase-dependent RNA Pol II eviction and ATPase-independent replisome disassembly — are coordinated within a single mitotic cell remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structure of full-length TTF2 with its partners","Mechanism switching between substrates (chromatin Pol II vs stalled replisomes) unknown","Several key mechanistic findings remain in preprint form"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140657","term_label":"ATP-dependent activity","supporting_discovery_ids":[7,9]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[9,10]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[9,10,12]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[7]},{"term_id":"GO:0005694","term_label":"chromosome","supporting_discovery_ids":[7]}],"pathway":[{"term_id":"R-HSA-1640170","term_label":"Cell Cycle","supporting_discovery_ids":[7,9,11]},{"term_id":"R-HSA-69306","term_label":"DNA Replication","supporting_discovery_ids":[9,10]},{"term_id":"R-HSA-8953854","term_label":"Metabolism of RNA","supporting_discovery_ids":[6]}],"complexes":[],"partners":["TRAIP","POLE2","CDC5L","CDC20"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9UNY4","full_name":"Transcription termination factor 2","aliases":["Lodestar homolog","RNA polymerase II termination factor","Transcription release factor 2","F2","HuF2"],"length_aa":1162,"mass_kda":129.6,"function":"DsDNA-dependent ATPase which acts as a transcription termination factor by coupling ATP hydrolysis with removal of RNA polymerase II from the DNA template. May contribute to mitotic transcription repression. May also be involved in pre-mRNA splicing","subcellular_location":"Cytoplasm; Nucleus","url":"https://www.uniprot.org/uniprotkb/Q9UNY4/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":true,"resolved_as":"","url":"https://depmap.org/portal/gene/TTF2","classification":"Common Essential","n_dependent_lines":846,"n_total_lines":1208,"dependency_fraction":0.7003311258278145},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"FKBP5","stoichiometry":0.2},{"gene":"POLR2K","stoichiometry":0.2},{"gene":"XPO1","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/TTF2","total_profiled":1310},"omim":[{"mim_id":"608504","title":"RHO GUANINE NUCLEOTIDE EXCHANGE FACTOR 15; ARHGEF15","url":"https://www.omim.org/entry/608504"},{"mim_id":"604718","title":"TRANSCRIPTION TERMINATION FACTOR 2; TTF2","url":"https://www.omim.org/entry/604718"},{"mim_id":"602617","title":"FORKHEAD BOX E1; FOXE1","url":"https://www.omim.org/entry/602617"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Cytosol","reliability":"Supported"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/TTF2"},"hgnc":{"alias_symbol":["HuF2","ZGRF6"],"prev_symbol":[]},"alphafold":{"accession":"Q9UNY4","domains":[{"cath_id":"-","chopping":"2-98","consensus_level":"medium","plddt":82.6758,"start":2,"end":98},{"cath_id":"3.40.50.10810","chopping":"558-619_637-708_724-835","consensus_level":"high","plddt":85.124,"start":558,"end":835},{"cath_id":"3.40.50.300","chopping":"992-1142_1153-1161","consensus_level":"medium","plddt":84.5667,"start":992,"end":1161}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9UNY4","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9UNY4-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9UNY4-F1-predicted_aligned_error_v6.png","plddt_mean":62.09},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=TTF2","jax_strain_url":"https://www.jax.org/strain/search?query=TTF2"},"sequence":{"accession":"Q9UNY4","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9UNY4.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9UNY4/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9UNY4"}},"corpus_meta":[{"pmid":"9697705","id":"PMC_9697705","title":"Mutation of the gene encoding human TTF-2 associated with thyroid agenesis, cleft palate and choanal atresia.","date":"1998","source":"Nature genetics","url":"https://pubmed.ncbi.nlm.nih.gov/9697705","citation_count":301,"is_preprint":false},{"pmid":"9214635","id":"PMC_9214635","title":"TTF-2, a new forkhead protein, shows a temporal expression in the developing thyroid which is consistent with a role in controlling the onset of differentiation.","date":"1997","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/9214635","citation_count":219,"is_preprint":false},{"pmid":"18084247","id":"PMC_18084247","title":"Diagnostic utility of thyroid transcription factors Pax8 and TTF-2 (FoxE1) in thyroid epithelial neoplasms.","date":"2007","source":"Modern pathology : an official journal of the United States and Canadian Academy of Pathology, Inc","url":"https://pubmed.ncbi.nlm.nih.gov/18084247","citation_count":204,"is_preprint":false},{"pmid":"12165566","id":"PMC_12165566","title":"A novel loss-of-function mutation in TTF-2 is associated with congenital hypothyroidism, thyroid agenesis and cleft palate.","date":"2002","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/12165566","citation_count":114,"is_preprint":false},{"pmid":"9287345","id":"PMC_9287345","title":"Transcriptional control of the forkhead thyroid transcription factor TTF-2 by thyrotropin, insulin, and insulin-like growth factor I.","date":"1997","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/9287345","citation_count":64,"is_preprint":false},{"pmid":"24105688","id":"PMC_24105688","title":"Contribution of ATM and FOXE1 (TTF2) to risk of papillary thyroid carcinoma in Belarusian children exposed to radiation.","date":"2013","source":"International journal of cancer","url":"https://pubmed.ncbi.nlm.nih.gov/24105688","citation_count":52,"is_preprint":false},{"pmid":"10944465","id":"PMC_10944465","title":"The thyroid transcription factor 2 (TTF-2) is a promoter-specific DNA-binding independent transcriptional repressor.","date":"2000","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/10944465","citation_count":50,"is_preprint":false},{"pmid":"16882747","id":"PMC_16882747","title":"A novel missense mutation in human TTF-2 (FKHL15) gene associated with congenital hypothyroidism but not athyreosis.","date":"2006","source":"The Journal of clinical endocrinology and metabolism","url":"https://pubmed.ncbi.nlm.nih.gov/16882747","citation_count":45,"is_preprint":false},{"pmid":"10329730","id":"PMC_10329730","title":"The interaction between the forkhead thyroid transcription factor TTF-2 and the constitutive factor CTF/NF-1 is required for efficient hormonal regulation of the thyroperoxidase gene transcription.","date":"1999","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/10329730","citation_count":42,"is_preprint":false},{"pmid":"20453517","id":"PMC_20453517","title":"Spectrum of Human Foxe1/TTF2 Mutations.","date":"2010","source":"Hormone research in paediatrics","url":"https://pubmed.ncbi.nlm.nih.gov/20453517","citation_count":41,"is_preprint":false},{"pmid":"15320969","id":"PMC_15320969","title":"Genetic analysis of TTF-2 gene in children with congenital hypothyroidism and cleft palate, congenital hypothyroidism, or isolated cleft palate.","date":"2004","source":"Thyroid : official journal of the American Thyroid Association","url":"https://pubmed.ncbi.nlm.nih.gov/15320969","citation_count":19,"is_preprint":false},{"pmid":"15467445","id":"PMC_15467445","title":"Rescue of the TTF2 knockdown phenotype with an siRNA-resistant replacement vector.","date":"2004","source":"Cell cycle (Georgetown, Tex.)","url":"https://pubmed.ncbi.nlm.nih.gov/15467445","citation_count":15,"is_preprint":false},{"pmid":"12927788","id":"PMC_12927788","title":"hLodestar/HuF2 interacts with CDC5L and is involved in pre-mRNA splicing.","date":"2003","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/12927788","citation_count":14,"is_preprint":false},{"pmid":"22304410","id":"PMC_22304410","title":"Overexpression of mouse TTF-2 gene causes cleft palate.","date":"2012","source":"Journal of cellular and molecular medicine","url":"https://pubmed.ncbi.nlm.nih.gov/22304410","citation_count":11,"is_preprint":false},{"pmid":"26356687","id":"PMC_26356687","title":"Replication and Meta-Analysis of Common Gene Mutations in TTF1 and TTF2 with Papillary Thyroid Cancer.","date":"2015","source":"Medicine","url":"https://pubmed.ncbi.nlm.nih.gov/26356687","citation_count":10,"is_preprint":false},{"pmid":"15223130","id":"PMC_15223130","title":"TTF-2 stimulates expression of 17 genes, including one novel thyroid-specific gene which might be involved in thyroid development.","date":"2004","source":"Molecular and cellular endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/15223130","citation_count":10,"is_preprint":false},{"pmid":"9446794","id":"PMC_9446794","title":"TTF-2 does not appear to be a key mediator of the effect of cyclic AMP on thyroglobulin gene transcription in primary cultured dog thyrocytes.","date":"1998","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/9446794","citation_count":8,"is_preprint":false},{"pmid":"39651145","id":"PMC_39651145","title":"TTF2 promotes replisome eviction from stalled forks in mitosis.","date":"2024","source":"bioRxiv : the preprint server for biology","url":"https://pubmed.ncbi.nlm.nih.gov/39651145","citation_count":6,"is_preprint":false},{"pmid":"40410652","id":"PMC_40410652","title":"Mutual regulation between cell cycle and transcription termination factor TTF2.","date":"2025","source":"Science China. Life sciences","url":"https://pubmed.ncbi.nlm.nih.gov/40410652","citation_count":2,"is_preprint":false},{"pmid":"22481925","id":"PMC_22481925","title":"Molecular Analysis of TTF-1 and TTF-2 Genes in Patients with Early Onset Papillary Thyroid Carcinoma.","date":"2012","source":"Journal of oncology","url":"https://pubmed.ncbi.nlm.nih.gov/22481925","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.03.17.643635","title":"The non-catalytic ε DNA polymerase subunit is an NPF motif recognition protein","date":"2025-03-17","source":"bioRxiv","url":"https://doi.org/10.1101/2025.03.17.643635","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.12.01.626218","title":"TTF2 drives mitotic replisome disassembly and MiDAS by coupling the TRAIP ubiquitin ligase to Polε","date":"2024-12-02","source":"bioRxiv","url":"https://doi.org/10.1101/2024.12.01.626218","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":12003,"output_tokens":3680,"usd":0.045604,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":11486,"output_tokens":2528,"usd":0.060315,"stage2_stop_reason":"end_turn"},"total_usd":0.105919,"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\": 1997,\n      \"finding\": \"TTF-2 (mouse) is a forkhead domain-containing DNA-binding protein that recognizes sites on both thyroglobulin (Tg) and thyroperoxidase (TPO) promoters; its expression is transiently downregulated in the developing thyroid just before onset of Tg and TPO gene expression, suggesting a role as a negative controller of thyroid-specific gene expression during development.\",\n      \"method\": \"cDNA cloning, DNA-binding assays, in situ hybridization/expression analysis in developing mouse thyroid\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — DNA binding demonstrated directly, temporal expression pattern correlated with functional hypothesis, single lab with two orthogonal methods\",\n      \"pmids\": [\"9214635\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1997,\n      \"finding\": \"TTF-2 mRNA levels are transcriptionally upregulated by TSH (via cAMP/forskolin), insulin, and IGF-I in FRTL-5 thyroid cells in a dose- and time-dependent manner requiring ongoing protein synthesis, positioning TTF-2 as a mediator of hormonal transcriptional activation of thyroid-specific genes.\",\n      \"method\": \"Northern blot, nuclear run-off transcription assay, pharmacological treatment of FRTL-5 cells\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — run-off assays confirm transcriptional regulation, two orthogonal methods, single lab\",\n      \"pmids\": [\"9287345\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1998,\n      \"finding\": \"A missense mutation (Ala65Val) within the forkhead domain of human TTF-2 (FKHL15/FOXE1) causes impaired DNA binding and loss of transcriptional function, establishing that DNA-binding activity of the forkhead domain is required for TTF-2's role in thyroid and palate development.\",\n      \"method\": \"Homozygosity mapping, direct sequencing, DNA-binding assay, transcriptional reporter assay with mutant protein\",\n      \"journal\": \"Nature genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — mutagenesis with functional validation (DNA binding + transcription assay), replicated by subsequent independent mutation studies\",\n      \"pmids\": [\"9697705\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1999,\n      \"finding\": \"TTF-2 physically interacts with CTF/NF-1 proteins (specifically CTF/NF1-C, which is itself hormonally regulated by TSH/cAMP/insulin) at the TPO promoter; this interaction is required for efficient hormonal regulation of TPO gene expression, and spacing between their binding sites is critical for promoter activity.\",\n      \"method\": \"GST pull-down assay, transfection/reporter assays, protein-DNA interaction (EMSA), spacing mutagenesis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — GST pull-down establishing direct interaction, mutagenesis of binding sites, transcriptional reporter assays, multiple orthogonal methods in one study\",\n      \"pmids\": [\"10329730\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"TTF-2 acts as a promoter-specific, DNA-binding-independent transcriptional repressor of TTF-1 and Pax-8 activity; the minimal repressor domain functions as an independent domain and repression occurs without TTF-2 binding DNA, suggesting it interferes with a specific cofactor required for TTF-1 and Pax-8 activity.\",\n      \"method\": \"Transcriptional reporter assays, domain deletion/mutagenesis analysis, co-transfection experiments\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — functional domain mapping with mutagenesis and reporter assays, single lab\",\n      \"pmids\": [\"10944465\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"A second missense mutation in the forkhead domain of TTF-2 (S57N) causes impaired DNA binding and partial loss of transcriptional function, confirming that the forkhead domain mediates DNA binding necessary for TTF-2 function in thyroid and palate development.\",\n      \"method\": \"Direct sequencing, DNA-binding assay, transcriptional reporter assay with mutant protein\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — independent replication of mechanism (DNA binding + transcription) established by a second mutation in the same domain across independent labs\",\n      \"pmids\": [\"12165566\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"HuF2 (TTF2/hLodestar), a SNF2-family ATPase, interacts with the pre-mRNA splicing factor CDC5L in yeast two-hybrid and HeLa nuclear extract, associates with human splicing complexes, and a truncated HuF2 polypeptide overlapping the CDC5L-binding region inhibits pre-mRNA splicing by disrupting spliceosome assembly.\",\n      \"method\": \"Yeast two-hybrid, co-immunoprecipitation from HeLa nuclear extract, in vitro splicing inhibition assay, spliceosome assembly assay\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal interaction shown in two systems plus functional splicing inhibition, single lab\",\n      \"pmids\": [\"12927788\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"TTF2 (human SNF2-family ATPase) is an RNA polymerase II termination factor responsible for mitotic repression of transcription elongation; siRNA-mediated knockdown of TTF2 causes retention of RNA polymerase II on condensed mitotic chromosomes, and this phenotype is rescued by expression of an siRNA-resistant GFP-TTF2 replacement vector, proving TTF2 is directly responsible.\",\n      \"method\": \"siRNA knockdown, rescue experiment with siRNA-resistant GFP-TTF2 replacement vector, immunofluorescence microscopy of mitotic chromosomes\",\n      \"journal\": \"Cell cycle (Georgetown, Tex.)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — knockdown phenotype rescued by siRNA-resistant construct, rigorous genetic epistasis, published peer-reviewed study\",\n      \"pmids\": [\"15467445\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"A third missense mutation (R102C) within the forkhead DNA-binding domain of TTF-2 causes complete loss of DNA binding and transcriptional inactivity, further confirming the forkhead domain as the essential functional domain for DNA binding.\",\n      \"method\": \"Direct sequencing, DNA-binding assay, transcriptional reporter assay with mutant protein\",\n      \"journal\": \"The Journal of clinical endocrinology and metabolism\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — independent third mutation confirming same mechanism, replicated across multiple labs\",\n      \"pmids\": [\"16882747\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"TTF2 (SWI/SNF ATPase) promotes replisome disassembly at stalled replication forks in mitosis by tethering the TRAIP E3 ubiquitin ligase to the CMG helicase via: (1) an N-terminal Zinc finger domain binding phosphorylated TRAIP (phosphorylation by mitotic Cyclin B-CDK1), and (2) an adjacent TTF2 peptide contacting CMG-associated DNA polymerase ε (Polε/POLE2). This TRAIP-TTF2-Polε bridge is independent of TTF2 ATPase activity and is essential for CMG unloading and stalled fork cleavage. In contrast, RNAPII eviction from mitotic chromosomes requires TTF2 ATPase activity.\",\n      \"method\": \"Xenopus egg extract replisome disassembly assay, domain mutagenesis, phosphorylation analysis, co-immunoprecipitation, biochemical reconstitution\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — reconstitution in Xenopus system, domain mutagenesis, multiple orthogonal biochemical methods, independently replicated by two concurrent preprints\",\n      \"pmids\": [\"39651145\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"TTF2 couples the TRAIP ubiquitin ligase to DNA Polymerase ε (Polε) via tandem Zinc fingers recognizing phosphorylated TRAIP and a motif binding POLE2, causing TRAIP to ubiquitylate CMG helicase to trigger replisome disassembly and Mitotic DNA Synthesis (MiDAS); TTF2 ATPase activity is separately required for RNA Pol II removal from mitotic chromosomes.\",\n      \"method\": \"Biochemical reconstitution, co-immunoprecipitation, domain mutagenesis, ubiquitylation assay, MiDAS assay\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — independent replication of TTF2-TRAIP-Polε mechanism by a second lab using orthogonal methods\",\n      \"pmids\": [\"bio_10.1101_2024.12.01.626218\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"TTF2 protein levels oscillate during the cell cycle (high in S and G2/M, low in late mitosis and G1); TTF2 is ubiquitinated by APC/C-CDH1 and degraded via the proteasome; TTF2 binds CDC20 and prevents mitotic checkpoint complex (MCC) formation during normal mitosis; when TTF2 is degraded by APC/C-CDH1 upon persistent G2/M arrest, CDC20 is released to promote MCC assembly.\",\n      \"method\": \"Cell cycle synchronization/flow cytometry, co-immunoprecipitation, ubiquitination assay, siRNA knockdown/overexpression with cell cycle phenotype readout, proteasome inhibitor treatment\",\n      \"journal\": \"Science China. Life sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods (Co-IP, ubiquitination assay, genetic perturbation), single lab, not yet independently replicated\",\n      \"pmids\": [\"40410652\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"TTF2 contains an NPF motif that binds to the non-catalytic POLE2 subunit of DNA polymerase ε with micromolar affinity; mutation of this NPF motif abolishes binding in cell extracts.\",\n      \"method\": \"Native holdup assay (quantitative peptide affinity), mutational analysis, proteome-scale affinity screen, AlphaFold structural prediction\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — quantitative binding assay with mutagenesis confirmation, single lab, preprint, consistent with independent structural prediction\",\n      \"pmids\": [\"bio_10.1101_2025.03.17.643635\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 1998,\n      \"finding\": \"TTF-2 DNA-binding activity is detectable in unstimulated dog thyrocytes and increases with forskolin treatment, but mutation of the TTF-2 binding site in the thyroglobulin promoter leaves cAMP-dependent activity largely intact, indicating TTF-2 does NOT play a dominant role in cAMP-dependent control of thyroglobulin gene transcription in primary dog thyrocytes (negative finding).\",\n      \"method\": \"Nuclear extract binding assay with radiolabeled probe, transient transfection reporter assay with site-directed mutagenesis of TTF-2 binding site\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — two orthogonal methods, but a negative/contradictory result relative to FRTL-5 cell findings; single lab\",\n      \"pmids\": [\"9446794\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"TTF2 is a multifunctional protein with two distinct molecular identities: (1) as FOXE1/TTF-2, a forkhead-domain transcription factor that binds thyroid gene promoters (Tg, TPO) via its forkhead domain, acts as a DNA-binding-independent repressor of TTF-1/Pax-8, physically interacts with CTF/NF-1 for hormonal regulation of TPO, and is regulated transcriptionally by TSH/cAMP and insulin; and (2) as HuF2/TTF2, a SNF2-family ATPase that uses its ATPase activity to evict RNA polymerase II from mitotic chromosomes, interacts with the splicing factor CDC5L to participate in pre-mRNA splicing, and—through an ATPase-independent mechanism—bridges the TRAIP E3 ubiquitin ligase to DNA polymerase ε (POLE2) via an N-terminal Zinc finger recognizing CDK1-phosphorylated TRAIP and an NPF motif binding POLE2, thereby directing CMG helicase ubiquitylation and replisome disassembly at stalled forks in mitosis; additionally, TTF2 protein oscillates through the cell cycle, is degraded by APC/C-CDH1, and regulates mitotic checkpoint complex assembly by sequestering CDC20.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"The TTF2 timeline describes two distinct proteins under colliding symbols, and the on-target gene for this entry is the human SNF2-family ATPase TTF2 (HuF2/hLodestar), a cell-cycle-regulated machine that clears chromatin-bound machinery during mitosis [#7, #9]. TTF2 functions as an RNA polymerase II termination factor that uses its ATPase activity to evict RNA Pol II from condensed mitotic chromosomes; this role is genetically defined, as knockdown causes RNA Pol II retention that is rescued by an siRNA-resistant TTF2 [#7]. In an ATPase-independent capacity, TTF2 acts as a molecular bridge that drives replisome disassembly at stalled mitotic replication forks: an N-terminal zinc finger recognizes Cyclin B-CDK1-phosphorylated TRAIP while an adjacent NPF motif binds the non-catalytic POLE2 subunit of DNA polymerase epsilon, tethering the TRAIP E3 ubiquitin ligase to the CMG helicase to direct CMG ubiquitylation, fork cleavage, and mitotic DNA synthesis [#9, #10, #12]. TTF2 protein oscillates across the cell cycle and is destroyed by APC/C-CDH1, and it also sequesters CDC20 to restrain mitotic checkpoint complex assembly until its degradation releases CDC20 [#11]. Separately, TTF2 associates with the spliceosome through the splicing factor CDC5L [#6]. The thyroid transcription-factor findings in this corpus ([#0]–[#5], [#8], [#13]) describe FOXE1/TTF-2, a different forkhead protein sharing the 'TTF-2' name, and are not part of this gene's mechanism.\",\n  \"teleology\": [\n    {\n      \"year\": 2003,\n      \"claim\": \"Established the first molecular partner of the SNF2-family ATPase HuF2/TTF2, linking it to pre-mRNA splicing and indicating a nuclear RNA-processing function.\",\n      \"evidence\": \"Yeast two-hybrid and Co-IP from HeLa nuclear extract identifying CDC5L interaction, plus a dominant-negative splicing-inhibition assay\",\n      \"pmids\": [\"12927788\"],\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Does not define whether ATPase activity is required for splicing-complex association\", \"Functional role of the CDC5L interaction in normal splicing not resolved beyond a truncation-based inhibition\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Defined TTF2 as the factor responsible for mitotic transcriptional repression by showing it is required to remove RNA Pol II from condensed chromosomes.\",\n      \"evidence\": \"siRNA knockdown with siRNA-resistant GFP-TTF2 rescue and immunofluorescence of mitotic chromosomes\",\n      \"pmids\": [\"15467445\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Did not biochemically separate ATPase-dependent from ATPase-independent activities\", \"Mechanism of Pol II eviction at molecular resolution not established\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Resolved an ATPase-independent function: TTF2 bridges TRAIP to the replisome to trigger CMG unloading at stalled mitotic forks, separating this activity from its ATPase-dependent Pol II eviction.\",\n      \"evidence\": \"Xenopus egg extract replisome disassembly reconstitution, domain mutagenesis, phosphorylation analysis, and Co-IP, independently corroborated by a concurrent preprint\",\n      \"pmids\": [\"39651145\", \"bio_10.1101_2024.12.01.626218\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Both reports are preprints\", \"Structural basis of simultaneous TRAIP and Polε engagement not solved\", \"In vivo consequences of disrupting only the bridge in human cells not detailed\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Mapped the POLE2-binding determinant to a specific NPF motif, providing the molecular contact point by which TTF2 docks onto DNA polymerase epsilon.\",\n      \"evidence\": \"Native holdup quantitative affinity assay with NPF-motif mutagenesis and AlphaFold prediction\",\n      \"pmids\": [\"bio_10.1101_2025.03.17.643635\"],\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Single-lab preprint\", \"Micromolar affinity functional relevance in the intact replisome not validated\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Connected TTF2 abundance to cell-cycle control, showing APC/C-CDH1-driven degradation and CDC20 sequestration that modulates mitotic checkpoint complex assembly.\",\n      \"evidence\": \"Cell-cycle synchronization, Co-IP, ubiquitination and proteasome-inhibitor assays, and genetic perturbation with cell-cycle readouts\",\n      \"pmids\": [\"40410652\"],\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Single lab, not independently replicated\", \"Whether CDC20 sequestration is direct and how it integrates with the TRAIP/replisome role is unresolved\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How TTF2's two biochemical modes — ATPase-dependent RNA Pol II eviction and ATPase-independent replisome disassembly — are coordinated within a single mitotic cell remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"No structure of full-length TTF2 with its partners\", \"Mechanism switching between substrates (chromatin Pol II vs stalled replisomes) unknown\", \"Several key mechanistic findings remain in preprint form\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140657\", \"supporting_discovery_ids\": [7, 9]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [9, 10]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [9, 10, 12]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [7]},\n      {\"term_id\": \"GO:0005694\", \"supporting_discovery_ids\": [7]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1640170\", \"supporting_discovery_ids\": [7, 9, 11]},\n      {\"term_id\": \"R-HSA-69306\", \"supporting_discovery_ids\": [9, 10]},\n      {\"term_id\": \"R-HSA-8953854\", \"supporting_discovery_ids\": [6]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"TRAIP\", \"POLE2\", \"CDC5L\", \"CDC20\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}