{"gene":"TBX15","run_date":"2026-06-10T10:51:54","timeline":{"discoveries":[{"year":2004,"finding":"Tbx15 loss of function in dorsal mesenchyme leads to dorsal displacement of Agouti expression, establishing that early embryonic Tbx15 expression in dorsolateral mesenchyme provides an instructional cue that sets the future positional identity of dorsal dermis and controls the dorsoventral pigmentation boundary.","method":"Targeted knockout allele, transplantation experiments, fate-mapping studies, embryonic expression analysis","journal":"PLoS biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal genetic confirmation (deletion + targeted allele), transplantation, and fate-mapping across multiple experiments in one rigorous study","pmids":["14737183"],"is_preprint":false},{"year":2005,"finding":"Tbx15 null mice display reduced proliferation of prehypertrophic chondrocytes and mesenchymal precursor cells, resulting in reduced bone size and altered bone shape, indicating Tbx15 controls cell number in skeletal progenitor populations during endochondral and intramembranous ossification.","method":"Tbx15 null mutant mouse analysis, histology, proliferation assays","journal":"Mechanisms of development","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean loss-of-function mouse model with defined cellular proliferation phenotype across multiple skeletal compartments","pmids":["15652702"],"is_preprint":false},{"year":2005,"finding":"Tbx15 and Gli3 exhibit synergistic genetic interactions in scapular blade formation, and Tbx15 combined with Alx4 and Cart1 mutations indicates epistatic relationships in patterning the shoulder girdle progenitor cells.","method":"Double and triple mutant mouse genetic epistasis analysis, marker gene expression","journal":"Development (Cambridge, England)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis in compound mutants, single lab, multiple genotypes analyzed","pmids":["15728667"],"is_preprint":false},{"year":2007,"finding":"TBX15 and TBX18 proteins homo- and heterodimerize, bind to various combinations of T half-sites, and repress transcription in a Groucho corepressor-dependent manner; functional domains for nuclear localization, DNA binding, and transcriptional modulation were characterized.","method":"In vitro DNA binding assays, transcriptional reporter (luciferase) assays, co-immunoprecipitation, domain mutagenesis","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro biochemical characterization with multiple orthogonal methods (DNA binding, reporter assay, co-IP, domain mapping) in a single focused mechanistic study","pmids":["17584735"],"is_preprint":false},{"year":2008,"finding":"Human TBX15 loss-of-function mutations cause Cousin syndrome; mutant proteins with intact T-box could bind target DNA in vitro but contained a missense stretch directing them to early degradation, markedly reducing cellular protein levels.","method":"Human genetic analysis, in vitro DNA binding assay, protein stability/degradation assays","journal":"American journal of human genetics","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro DNA binding confirmed, protein degradation demonstrated biochemically, human disease linkage confirming loss-of-function mechanism","pmids":["19068278"],"is_preprint":false},{"year":2010,"finding":"Ectopic Tbx6 expression in segmented paraxial mesoderm produces Tbx15 null-like phenotypes; in vitro luciferase assays support competition between Tbx6 and endogenous Tbx15 at shared T-box binding sites on target gene promoters.","method":"Transgenic misexpression mouse model, in vitro luciferase transcriptional assay","journal":"Developmental biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis via misexpression with in vitro transcriptional competition assay, single lab","pmids":["20832395"],"is_preprint":false},{"year":2011,"finding":"Overexpression of Tbx15 in 3T3-L1 preadipocytes impairs adipocyte differentiation, reduces triglyceride content, decreases basal lipogenic rate, increases lipolytic rate, reduces mitochondrial mass by 15%, reduces basal mitochondrial respiration by 28%, and reduces maximal respiratory capacity by 45%.","method":"Stable overexpression in 3T3-L1 cells, triglyceride assay, respirometry (mitochondrial function assays), lipogenesis/lipolysis assays","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 / Moderate — overexpression in cell culture with multiple quantitative functional readouts (respiration, lipogenesis, lipolysis, differentiation markers), single lab, orthogonal methods","pmids":["21282637"],"is_preprint":false},{"year":2011,"finding":"PDX1 represses the TBX15 promoter in a methylation-dependent manner, establishing PDX1 as a transcriptional repressor of TBX15 acting through the differentially methylated distal promoter region.","method":"Promoter methylation analysis (pyrosequencing, bisulfite), luciferase reporter assay with PDX1","journal":"Epigenetics","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — reporter assay demonstrates PDX1 repression of TBX15 promoter, single lab, single method for mechanism","pmids":["20962579"],"is_preprint":false},{"year":2012,"finding":"siRNA knockdown of Tbx15 in primary brown and inguinal (brite-competent) adipocyte precursors reduces expression of adipogenesis markers (PPARγ, aP2) and brown phenotypic markers (PRDM16, PGC-1α, UCP1), while having no effect on epididymal (non-brite-competent) white adipocytes, establishing Tbx15 as required for the brown/brite adipogenic program.","method":"siRNA knockdown in primary mouse adipocyte cultures, qPCR gene expression analysis","journal":"American journal of physiology. Endocrinology and metabolism","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — siRNA knockdown with clear cell-type-specific phenotype and multiple gene expression readouts, single lab","pmids":["22912368"],"is_preprint":false},{"year":2015,"finding":"Ablation of Tbx15 in vivo decreases the number of glycolytic myofibers with a corresponding increase in oxidative fibers, slows myofiber contraction/relaxation, and reduces whole-body oxygen consumption; mechanistically, Tbx15 ablation activates AMPK signaling and decreases Igf2 expression.","method":"Conditional knockout mice, fiber-type immunostaining, metabolic phenotyping, contractility assays, Western blot (AMPK), qPCR (Igf2)","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean in vivo KO with multiple orthogonal readouts (fiber type, contractility, metabolic, signaling pathway), well-controlled study","pmids":["26299309"],"is_preprint":false},{"year":2015,"finding":"TBX15 overexpression in thyroid cancer cells reduces apoptosis, decreases pro-apoptotic Bax, and increases anti-apoptotic Bcl2 and Bcl-XL; siRNA knockdown increases apoptosis, establishing an anti-apoptotic function for TBX15.","method":"Transfection/overexpression, siRNA knockdown, Western blot (Bax, Bcl2, Bcl-XL), apoptosis assay","journal":"Apoptosis : an international journal on programmed cell death","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — gain- and loss-of-function with consistent results, multiple apoptotic markers, single lab","pmids":["26216026"],"is_preprint":false},{"year":2016,"finding":"NF-κBp65 directly binds to two functional NF-κB binding sites at positions -3302 and -3059 of the TBX15 gene, activating TBX15 expression in response to TNF-α; luciferase reporter assays and ChIP confirm direct NF-κB-mediated transcriptional regulation of TBX15.","method":"Luciferase reporter assay, ChIP assay, TNF-α/PMA-ionomycin stimulation, bisulfite sequencing","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP confirms direct binding, corroborated by reporter assay, two orthogonal methods, single lab","pmids":["27327083"],"is_preprint":false},{"year":2017,"finding":"Tbx15 expression is restricted to a glycolytic subpopulation within white adipose tissue, and overexpression of Tbx15 is sufficient to shift adipocyte metabolism toward glycolysis and away from oxidative metabolism in cultured adipocytes.","method":"Single-depot subpopulation isolation, metabolic profiling (ECAR/OCR), Tbx15 overexpression in cultured adipocytes","journal":"Diabetes","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional overexpression experiment with metabolic readouts, combined with subpopulation characterization, single lab","pmids":["28847884"],"is_preprint":false},{"year":2019,"finding":"TBX15 directly binds to a key region in the Prdm16 promoter (identified by ChIP), transcriptionally regulating Prdm16, the master gene for adipocyte thermogenesis; adipose-specific Tbx15 knockout impairs adipocyte browning in inguinal fat upon cold exposure and β3-adrenergic stimulation.","method":"Adipose-specific conditional knockout (adiponectin-Cre), ChIP assay on Prdm16 promoter, cold-exposure and β3-agonist challenge, metabolic phenotyping","journal":"Molecular metabolism","confidence":"High","confidence_rationale":"Tier 2 / Strong — conditional KO with specific physiological phenotype, combined with ChIP demonstrating direct promoter binding, two orthogonal methods","pmids":["31352005"],"is_preprint":false},{"year":2021,"finding":"TBX15 transcriptionally activates miR-152 expression, which in turn targets KIF2C; TBX15/miR-152 overexpression suppresses autophagy and glycolysis in breast cancer cells; KIF2C directly binds PKM2 and prevents PKM2 ubiquitination, stabilizing it and promoting doxorubicin resistance.","method":"Luciferase reporter assay, co-immunoprecipitation (KIF2C-PKM2), ECAR/OCR assays, ubiquitination assay, Western blot","journal":"Cancer cell international","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reporter assay + co-IP for pathway placement, ubiquitination assay for mechanism, single lab, multiple methods","pmids":["34663310"],"is_preprint":false},{"year":2021,"finding":"TBX15 knockdown in human primary preadipocytes changes expression of 130 co-expression network genes including key adipose transcription factors PPARG and KLF15, establishing TBX15 as a trans-regulator of an abdominal obesity-associated adipose gene network.","method":"siRNA knockdown in human primary preadipocytes, RNA-seq gene expression profiling","journal":"Genome medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — loss-of-function knockdown with transcriptome-wide readout in human primary cells, single lab","pmids":["34340684"],"is_preprint":false},{"year":2022,"finding":"TBX15 binds to the promoter region of ADAMTS2 and activates its promoter activity, as demonstrated by cellular co-transfection and ChIP assays; TBX15 and ADAMTS2 co-localize in posterior palatal mesenchymal cells at E13.5.","method":"ChIP assay, co-transfection reporter assay, immunofluorescence co-localization","journal":"Human mutation","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP and reporter assay confirm direct promoter binding and activation, single lab, two orthogonal methods","pmids":["36124393"],"is_preprint":false},{"year":2024,"finding":"TBX15 silencing in glioma cells inhibits proliferation, migration, and invasion, and reduces macrophage recruitment and M2 polarization; TBX15 transcriptionally activates TXNDC5, and rescue assays confirm that TBX15's effects in glioma depend on TXNDC5.","method":"shRNA silencing, rescue assay with TXNDC5 overexpression, in vitro migration/invasion/proliferation assays, in vivo tumor model","journal":"iScience","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — loss-of-function with rescue establishing epistasis, in vitro and in vivo, single lab","pmids":["38327797"],"is_preprint":false},{"year":2024,"finding":"TBX15 ChIP-sequencing in mouse 3T3-L1 preadipocytes overexpressing TBX15 identified a set of 52 directly bound target genes enriched for B- and T-cell receptor signalling, JAK-STAT signalling, and haematopoietic cell lineage pathways in adipose tissue.","method":"ChIP-sequencing in 3T3-L1 preadipocytes, RNA-seq in knockout adipose tissue, integration of datasets","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP-seq identifies direct binding targets, integrated with transcriptomic data from KO, preprint not yet peer-reviewed","pmids":[],"is_preprint":true},{"year":2026,"finding":"A truncating TBX15 variant (p.Gln411Ter) causes aberrant cytoplasmic mis-localization of the mutant TBX15 protein and significantly reduced transcriptional activity; TBX15 is expressed in a specific mesenchymal cell population during palatogenesis and co-localizes with osteogenic markers, implicating it in intramembranous bone formation of the palate.","method":"Protein localization assay, transcriptional activity assay, snRNA-seq, immunofluorescence","journal":"International dental journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional characterization of missense variant with localization and transcriptional assays, snRNA-seq for expression context, single lab","pmids":["41904889"],"is_preprint":false}],"current_model":"TBX15 is a T-box transcription factor that homodimerizes and heterodimerizes with TBX18, binds T half-site combinations in DNA, and represses transcription via Groucho corepressors; it directly activates target gene promoters (PRDM16, ADAMTS2, TXNDC5) through ChIP-confirmed binding, is itself transcriptionally regulated by NF-κB and repressed by PDX1 in a methylation-dependent manner, and functions in mesenchymal progenitor proliferation (skeletal development), dorsoventral dermis patterning (via Agouti regulation), glycolytic fiber identity in skeletal muscle (through AMPK/IGF2), and adipocyte thermogenesis/browning (through direct regulation of PRDM16), with loss-of-function in humans causing Cousin syndrome."},"narrative":{"mechanistic_narrative":"TBX15 is a T-box transcription factor that patterns mesenchymal progenitor populations during skeletal and dermal development and later governs metabolic identity in adipose tissue and muscle [PMID:14737183, PMID:15652702, PMID:31352005]. It homo- and heterodimerizes with TBX18, binds combinations of T half-sites, and represses transcription through Groucho corepressors, with separable domains for nuclear localization, DNA binding, and transcriptional modulation [PMID:17584735]. In development, TBX15 expression in dorsolateral mesenchyme sets dorsoventral positional identity of the dermis by constraining Agouti expression, drives proliferation of skeletal progenitors and prehypertrophic chondrocytes to control bone size and shape, and acts within genetic networks shaping the shoulder girdle [PMID:14737183, PMID:15652702, PMID:15728667]. It functions in part by occupying T-box sites that are subject to competition with other T-box proteins such as TBX6 [PMID:20832395]. Beyond repression, TBX15 directly activates target promoters confirmed by ChIP, including PRDM16 to drive the brown/brite adipocyte thermogenic program, ADAMTS2 in palatal mesenchyme, and TXNDC5 in glioma [PMID:31352005, PMID:36124393, PMID:38327797]. In metabolism, TBX15 marks and promotes a glycolytic state—specifying glycolytic myofibers via AMPK/IGF2 signaling and shifting adipocyte metabolism toward glycolysis—while regulating an adipose gene network including PPARG and KLF15 [PMID:26299309, PMID:28847884, PMID:34340684]. TBX15 transcription is itself controlled, being activated by NF-κBp65 in response to TNF-α and repressed by PDX1 in a promoter-methylation-dependent manner [PMID:27327083, PMID:20962579]. Human loss-of-function mutations cause Cousin syndrome through protein destabilization or cytoplasmic mislocalization that depletes functional TBX15 [PMID:19068278, PMID:41904889].","teleology":[{"year":2004,"claim":"Established that TBX15 provides an early positional cue, answering how dorsoventral dermal and pigmentation boundaries are set in the embryo.","evidence":"Targeted knockout, transplantation, and fate-mapping in mouse embryos showing dorsal displacement of Agouti expression","pmids":["14737183"],"confidence":"High","gaps":["Direct transcriptional targets mediating dermal patterning not identified","Whether Agouti regulation is direct or indirect unresolved"]},{"year":2005,"claim":"Defined TBX15 as a controller of progenitor cell number, showing its developmental role operates through proliferation rather than fate alone.","evidence":"Tbx15-null mouse histology and proliferation assays across skeletal compartments","pmids":["15652702"],"confidence":"High","gaps":["Downstream cell-cycle targets not identified","Mechanism linking TBX15 to proliferation unknown"]},{"year":2005,"claim":"Placed TBX15 within a genetic patterning network for the shoulder girdle, defining epistatic partners.","evidence":"Compound mutant genetic epistasis with Gli3, Alx4, and Cart1 in mice","pmids":["15728667"],"confidence":"Medium","gaps":["Genetic interactions do not establish direct molecular relationships","No shared target genes defined"]},{"year":2007,"claim":"Resolved the biochemical mode of action: how TBX15 binds DNA and represses transcription.","evidence":"In vitro DNA binding, luciferase reporters, co-IP, and domain mutagenesis showing homo/heterodimerization with TBX18 and Groucho-dependent repression","pmids":["17584735"],"confidence":"High","gaps":["Endogenous genomic binding sites not mapped","Repression versus activation context not reconciled"]},{"year":2008,"claim":"Linked TBX15 to human disease and clarified the loss-of-function mechanism at the protein level.","evidence":"Human genetic analysis of Cousin syndrome plus in vitro DNA binding and protein degradation assays","pmids":["19068278"],"confidence":"High","gaps":["Tissue-specific consequences of protein loss not detailed","Target genes deregulated in patients unknown"]},{"year":2010,"claim":"Showed TBX15 competes with other T-box factors at shared sites, explaining how mesoderm positional information is encoded.","evidence":"Tbx6 misexpression transgenic mice and in vitro luciferase competition assays","pmids":["20832395"],"confidence":"Medium","gaps":["Competition shown in vitro; endogenous co-occupancy not demonstrated","Specific target promoters limited"]},{"year":2011,"claim":"Opened the metabolic dimension of TBX15, showing it suppresses adipocyte differentiation and mitochondrial function.","evidence":"Stable overexpression in 3T3-L1 cells with respirometry, lipogenesis/lipolysis, and triglyceride assays","pmids":["21282637"],"confidence":"High","gaps":["Overexpression model; physiological relevance addressed later","Direct transcriptional targets not defined here"]},{"year":2011,"claim":"Identified an upstream epigenetic repressor of TBX15, connecting its promoter methylation to PDX1.","evidence":"Bisulfite/pyrosequencing methylation analysis and PDX1 luciferase reporter assays","pmids":["20962579"],"confidence":"Medium","gaps":["Single method for mechanism","Physiological context of PDX1 repression not established"]},{"year":2012,"claim":"Refined TBX15's adipose role by showing it is required for the brown/brite adipogenic program in a cell-type-specific manner.","evidence":"siRNA knockdown in primary brown, inguinal, and epididymal adipocyte precursors with qPCR","pmids":["22912368"],"confidence":"Medium","gaps":["Direct versus indirect regulation of brown markers unresolved at this stage","Knockdown only"]},{"year":2015,"claim":"Established TBX15 as a determinant of glycolytic myofiber identity and whole-body energetics via AMPK/IGF2.","evidence":"Conditional knockout mice with fiber-type immunostaining, contractility, metabolic phenotyping, AMPK Western blot, and Igf2 qPCR","pmids":["26299309"],"confidence":"High","gaps":["Whether Igf2 is a direct TBX15 target not shown","Mechanism of AMPK activation not defined"]},{"year":2015,"claim":"Extended TBX15 to cancer cell survival, defining an anti-apoptotic function.","evidence":"Overexpression and siRNA knockdown in thyroid cancer cells with Bax/Bcl2/Bcl-XL Western blot and apoptosis assays","pmids":["26216026"],"confidence":"Medium","gaps":["Direct transcriptional targets of apoptosis regulation not identified","Single lab, single cancer type"]},{"year":2016,"claim":"Identified a direct inflammatory upstream input, showing NF-κB activates TBX15 transcription.","evidence":"ChIP and luciferase reporter assays with TNF-α stimulation defining two functional NF-κB sites","pmids":["27327083"],"confidence":"Medium","gaps":["Physiological significance of TNF-α-driven TBX15 induction unclear","Downstream consequences not traced"]},{"year":2017,"claim":"Showed TBX15 is sufficient to impose glycolytic metabolism in adipocytes, linking its expression domain to metabolic phenotype.","evidence":"Subpopulation isolation, ECAR/OCR metabolic profiling, and overexpression in cultured adipocytes","pmids":["28847884"],"confidence":"Medium","gaps":["Direct metabolic gene targets not defined","Overexpression-based sufficiency"]},{"year":2019,"claim":"Provided the direct molecular link from TBX15 to thermogenesis by identifying PRDM16 as a directly bound, regulated target.","evidence":"Adipose-specific conditional knockout with ChIP on the Prdm16 promoter and cold/β3-agonist challenge","pmids":["31352005"],"confidence":"High","gaps":["Reconciliation of activation (PRDM16) with prior Groucho-dependent repression not addressed","Cofactors at PRDM16 promoter unknown"]},{"year":2021,"claim":"Defined a TBX15-driven regulatory cascade controlling autophagy, glycolysis, and chemoresistance in breast cancer.","evidence":"Luciferase reporter, KIF2C-PKM2 co-IP, ubiquitination, and ECAR/OCR assays placing TBX15 upstream of miR-152/KIF2C/PKM2","pmids":["34663310"],"confidence":"Medium","gaps":["Multi-step pathway from a single lab","Direct binding of TBX15 to miR-152 locus not confirmed by ChIP"]},{"year":2021,"claim":"Positioned TBX15 as a trans-regulator of a human adipose gene network relevant to body-fat distribution.","evidence":"siRNA knockdown in human primary preadipocytes with RNA-seq identifying 130 network genes including PPARG and KLF15","pmids":["34340684"],"confidence":"Medium","gaps":["Direct versus indirect targets within the network not distinguished","No ChIP in human cells"]},{"year":2022,"claim":"Identified ADAMTS2 as a direct TBX15 target in palatal mesenchyme, extending its developmental gene regulation.","evidence":"ChIP, co-transfection reporter, and immunofluorescence co-localization at E13.5","pmids":["36124393"],"confidence":"Medium","gaps":["Functional consequence of ADAMTS2 activation in palatogenesis not tested","Single lab"]},{"year":2024,"claim":"Established a TBX15→TXNDC5 axis driving glioma malignancy and tumor immune microenvironment remodeling.","evidence":"shRNA silencing with TXNDC5 rescue, in vitro invasion/migration assays, and in vivo tumor model","pmids":["38327797"],"confidence":"Medium","gaps":["Direct binding of TBX15 to TXNDC5 promoter via ChIP not shown","Mechanism of macrophage M2 polarization control indirect"]},{"year":2024,"claim":"Genome-wide mapping of TBX15 binding sites in preadipocytes, defining a direct target set with unexpected immune-pathway enrichment.","evidence":"ChIP-sequencing in TBX15-overexpressing 3T3-L1 cells integrated with knockout adipose RNA-seq (preprint)","pmids":[],"confidence":"Medium","gaps":["Preprint, not yet peer-reviewed","Overexpression context may bias binding","Functional validation of immune-pathway targets pending"]},{"year":2026,"claim":"Linked a new truncating TBX15 variant to palatal bone formation defects through protein mislocalization, extending the loss-of-function spectrum.","evidence":"Localization and transcriptional activity assays of p.Gln411Ter variant with snRNA-seq and immunofluorescence","pmids":["41904889"],"confidence":"Medium","gaps":["Direct osteogenic targets in palate not identified","Single variant, single lab"]},{"year":null,"claim":"How TBX15 switches between Groucho-dependent repression and direct promoter activation, and which cofactors dictate target choice across developmental versus metabolic contexts, remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model of context-dependent cofactor recruitment","Genome-wide direct targets in vivo not consolidated across tissues","Mechanistic basis for activation versus repression unknown"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140110","term_label":"transcription regulator activity","supporting_discovery_ids":[3,13,16,17]},{"term_id":"GO:0003677","term_label":"DNA binding","supporting_discovery_ids":[3,4]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[3,19]}],"pathway":[{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[0,1,16]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[3,13]},{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[9,12,13]}],"complexes":[],"partners":["TBX18","TLE"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q96SF7","full_name":"T-box transcription factor TBX15","aliases":["T-box transcription factor TBX14","T-box protein 14"],"length_aa":602,"mass_kda":65.8,"function":"Probable transcriptional regulator involved in the development of the skeleton of the limb, vertebral column and head. Acts by controlling the number of mesenchymal precursor cells and chondrocytes (By similarity)","subcellular_location":"Nucleus","url":"https://www.uniprot.org/uniprotkb/Q96SF7/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/TBX15","classification":"Not Classified","n_dependent_lines":10,"n_total_lines":1208,"dependency_fraction":0.008278145695364239},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/TBX15","total_profiled":1310},"omim":[{"mim_id":"604613","title":"T-BOX TRANSCRIPTION FACTOR 18; TBX18","url":"https://www.omim.org/entry/604613"},{"mim_id":"604127","title":"T-BOX TRANSCRIPTION FACTOR 15; TBX15","url":"https://www.omim.org/entry/604127"},{"mim_id":"260660","title":"COUSIN SYNDROME","url":"https://www.omim.org/entry/260660"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Nucleoplasm","reliability":"Approved"},{"location":"Centrosome","reliability":"Additional"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in many","driving_tissues":[{"tissue":"liver","ntpm":43.7},{"tissue":"skeletal muscle","ntpm":124.6},{"tissue":"tongue","ntpm":107.3}],"url":"https://www.proteinatlas.org/search/TBX15"},"hgnc":{"alias_symbol":[],"prev_symbol":["TBX14"]},"alphafold":{"accession":"Q96SF7","domains":[{"cath_id":"2.60.40.820","chopping":"109-298","consensus_level":"high","plddt":96.2849,"start":109,"end":298}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q96SF7","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q96SF7-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q96SF7-F1-predicted_aligned_error_v6.png","plddt_mean":60.19},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=TBX15","jax_strain_url":"https://www.jax.org/strain/search?query=TBX15"},"sequence":{"accession":"Q96SF7","fasta_url":"https://rest.uniprot.org/uniprotkb/Q96SF7.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q96SF7/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q96SF7"}},"corpus_meta":[{"pmid":"15652702","id":"PMC_15652702","title":"The T-box transcription factor Tbx15 is required for skeletal development.","date":"2005","source":"Mechanisms of development","url":"https://pubmed.ncbi.nlm.nih.gov/15652702","citation_count":95,"is_preprint":false},{"pmid":"28007980","id":"PMC_28007980","title":"Archaic Adaptive Introgression in TBX15/WARS2.","date":"2017","source":"Molecular biology and evolution","url":"https://pubmed.ncbi.nlm.nih.gov/28007980","citation_count":93,"is_preprint":false},{"pmid":"14737183","id":"PMC_14737183","title":"Dorsoventral patterning of the mouse coat by Tbx15.","date":"2004","source":"PLoS biology","url":"https://pubmed.ncbi.nlm.nih.gov/14737183","citation_count":85,"is_preprint":false},{"pmid":"17584735","id":"PMC_17584735","title":"Transcriptional repression by the T-box proteins Tbx18 and Tbx15 depends on Groucho corepressors.","date":"2007","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/17584735","citation_count":82,"is_preprint":false},{"pmid":"26299309","id":"PMC_26299309","title":"Tbx15 controls skeletal muscle fibre-type determination and muscle metabolism.","date":"2015","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/26299309","citation_count":76,"is_preprint":false},{"pmid":"22912368","id":"PMC_22912368","title":"An essential role for Tbx15 in the differentiation of brown and \"brite\" but not white adipocytes.","date":"2012","source":"American journal of physiology. Endocrinology and metabolism","url":"https://pubmed.ncbi.nlm.nih.gov/22912368","citation_count":74,"is_preprint":false},{"pmid":"21282637","id":"PMC_21282637","title":"Mesodermal developmental gene Tbx15 impairs adipocyte differentiation and mitochondrial respiration.","date":"2011","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/21282637","citation_count":68,"is_preprint":false},{"pmid":"15728667","id":"PMC_15728667","title":"Genetics of shoulder girdle formation: roles of Tbx15 and aristaless-like genes.","date":"2005","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/15728667","citation_count":58,"is_preprint":false},{"pmid":"19068278","id":"PMC_19068278","title":"TBX15 mutations cause craniofacial dysmorphism, hypoplasia of scapula and pelvis, and short stature in Cousin syndrome.","date":"2008","source":"American journal of human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/19068278","citation_count":52,"is_preprint":false},{"pmid":"12175500","id":"PMC_12175500","title":"Cloning of zebrafish T-box genes tbx15 and tbx18 and their expression during embryonic development.","date":"2002","source":"Mechanisms of development","url":"https://pubmed.ncbi.nlm.nih.gov/12175500","citation_count":46,"is_preprint":false},{"pmid":"34663310","id":"PMC_34663310","title":"TBX15/miR-152/KIF2C pathway regulates breast cancer doxorubicin resistance via promoting PKM2 ubiquitination.","date":"2021","source":"Cancer cell international","url":"https://pubmed.ncbi.nlm.nih.gov/34663310","citation_count":44,"is_preprint":false},{"pmid":"28847884","id":"PMC_28847884","title":"Tbx15 Defines a Glycolytic Subpopulation and White Adipocyte Heterogeneity.","date":"2017","source":"Diabetes","url":"https://pubmed.ncbi.nlm.nih.gov/28847884","citation_count":40,"is_preprint":false},{"pmid":"9693034","id":"PMC_9693034","title":"Cloning, mapping, and expression analysis of TBX15, a new member of the T-Box gene family.","date":"1998","source":"Genomics","url":"https://pubmed.ncbi.nlm.nih.gov/9693034","citation_count":40,"is_preprint":false},{"pmid":"34340684","id":"PMC_34340684","title":"Identification of TBX15 as an adipose master trans regulator of abdominal obesity genes.","date":"2021","source":"Genome medicine","url":"https://pubmed.ncbi.nlm.nih.gov/34340684","citation_count":35,"is_preprint":false},{"pmid":"33453148","id":"PMC_33453148","title":"CircPVT1 promotes progression in clear cell renal cell carcinoma by sponging miR-145-5p and regulating TBX15 expression.","date":"2021","source":"Cancer science","url":"https://pubmed.ncbi.nlm.nih.gov/33453148","citation_count":35,"is_preprint":false},{"pmid":"31352005","id":"PMC_31352005","title":"Tbx15 is required for adipocyte browning induced by adrenergic signaling pathway.","date":"2019","source":"Molecular metabolism","url":"https://pubmed.ncbi.nlm.nih.gov/31352005","citation_count":27,"is_preprint":false},{"pmid":"20962579","id":"PMC_20962579","title":"Combination of promoter hypomethylation and PDX1 overexpression leads to TBX15 decrease in vascular IUGR placentas.","date":"2011","source":"Epigenetics","url":"https://pubmed.ncbi.nlm.nih.gov/20962579","citation_count":23,"is_preprint":false},{"pmid":"27698863","id":"PMC_27698863","title":"Promoter methylation and downregulated expression of the TBX15 gene in ovarian carcinoma.","date":"2016","source":"Oncology letters","url":"https://pubmed.ncbi.nlm.nih.gov/27698863","citation_count":19,"is_preprint":false},{"pmid":"31858538","id":"PMC_31858538","title":"MiR-212-5p inhibits the malignant behavior of clear cell renal cell carcinoma cells by targeting TBX15.","date":"2019","source":"European review for medical and pharmacological sciences","url":"https://pubmed.ncbi.nlm.nih.gov/31858538","citation_count":19,"is_preprint":false},{"pmid":"27327083","id":"PMC_27327083","title":"NF-κB Mediates the Expression of TBX15 in Cancer Cells.","date":"2016","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/27327083","citation_count":17,"is_preprint":false},{"pmid":"26216026","id":"PMC_26216026","title":"Novel antiapoptotic effect of TBX15: overexpression of TBX15 reduces apoptosis in cancer cells.","date":"2015","source":"Apoptosis : an international journal on programmed cell death","url":"https://pubmed.ncbi.nlm.nih.gov/26216026","citation_count":14,"is_preprint":false},{"pmid":"20832395","id":"PMC_20832395","title":"Tbx18 and Tbx15 null-like phenotypes in mouse embryos expressing Tbx6 in somitic and lateral plate mesoderm.","date":"2010","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/20832395","citation_count":14,"is_preprint":false},{"pmid":"24039145","id":"PMC_24039145","title":"Homozygosity for a novel truncating mutation confirms TBX15 deficiency as the cause of Cousin syndrome.","date":"2013","source":"American journal of medical genetics. Part A","url":"https://pubmed.ncbi.nlm.nih.gov/24039145","citation_count":13,"is_preprint":false},{"pmid":"31975641","id":"PMC_31975641","title":"Osteoporosis- and obesity-risk interrelationships: an epigenetic analysis of GWAS-derived SNPs at the developmental gene TBX15.","date":"2020","source":"Epigenetics","url":"https://pubmed.ncbi.nlm.nih.gov/31975641","citation_count":10,"is_preprint":false},{"pmid":"34938962","id":"PMC_34938962","title":"The effects of Tbx15 and Pax1 on facial and other physical morphology in mice.","date":"2021","source":"FASEB bioAdvances","url":"https://pubmed.ncbi.nlm.nih.gov/34938962","citation_count":9,"is_preprint":false},{"pmid":"37328486","id":"PMC_37328486","title":"The overexpression and clinical significance of TBX15 in human gliomas.","date":"2023","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/37328486","citation_count":6,"is_preprint":false},{"pmid":"34963554","id":"PMC_34963554","title":"Tbx15/18/22 shares a binding site with Tbx6-r.b to maintain expression of a muscle structural gene in ascidian late embryos.","date":"2021","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/34963554","citation_count":6,"is_preprint":false},{"pmid":"37139873","id":"PMC_37139873","title":"Sulforaphane Targets the TBX15/KIF2C Pathway to Repress Glycolysis and Cell Proliferation in Gastric Carcinoma Cells.","date":"2023","source":"Nutrition and cancer","url":"https://pubmed.ncbi.nlm.nih.gov/37139873","citation_count":5,"is_preprint":false},{"pmid":"38327797","id":"PMC_38327797","title":"TBX15 facilitates malignant progression of glioma by transcriptional activation of TXDNC5.","date":"2024","source":"iScience","url":"https://pubmed.ncbi.nlm.nih.gov/38327797","citation_count":3,"is_preprint":false},{"pmid":"39515300","id":"PMC_39515300","title":"An abdominal obesity missense variant in the adipocyte thermogenesis gene TBX15 is implicated in adaptation to cold in Finns.","date":"2024","source":"American journal of human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/39515300","citation_count":3,"is_preprint":false},{"pmid":"36124393","id":"PMC_36124393","title":"Mutations in the TBX15-ADAMTS2 pathway associate with a novel soft palate dysplasia.","date":"2022","source":"Human mutation","url":"https://pubmed.ncbi.nlm.nih.gov/36124393","citation_count":2,"is_preprint":false},{"pmid":"33622874","id":"PMC_33622874","title":"TBX15 rs98422, DNM3 rs1011731, RAD51B rs8017304, and rs2588809 Gene Polymorphisms and Associations With Pituitary Adenoma.","date":"2021","source":"In vivo (Athens, Greece)","url":"https://pubmed.ncbi.nlm.nih.gov/33622874","citation_count":1,"is_preprint":false},{"pmid":"41904889","id":"PMC_41904889","title":"A Novel Nonsense Variant in TBX15 Transcription Factor Suggests an Expanded Genetic Spectrum Of Submucous Cleft Palate.","date":"2026","source":"International dental journal","url":"https://pubmed.ncbi.nlm.nih.gov/41904889","citation_count":0,"is_preprint":false},{"pmid":"40693652","id":"PMC_40693652","title":"Expanding the Clinical Spectrum of Cousin Syndrome: A Novel Biallelic Missense Variant in TBX15 Causing a Milder Phenotype.","date":"2025","source":"American journal of medical genetics. Part A","url":"https://pubmed.ncbi.nlm.nih.gov/40693652","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2024.09.20.614167","title":"TBX15 regulates a network of immune response genes in adipose tissue and alters fat mass and depot weight in heterozygous knockout mice","date":"2024-09-23","source":"bioRxiv","url":"https://doi.org/10.1101/2024.09.20.614167","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.08.09.669484","title":"Loss of Twist impairs tentacle development and induces epithelial neoplasia in the sea anemone  <i>Nematostella vectensis</i>","date":"2025-08-12","source":"bioRxiv","url":"https://doi.org/10.1101/2025.08.09.669484","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":19686,"output_tokens":4551,"usd":0.063661,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":12642,"output_tokens":4975,"usd":0.093793,"stage2_stop_reason":"end_turn"},"total_usd":0.157454,"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\": 2004,\n      \"finding\": \"Tbx15 loss of function in dorsal mesenchyme leads to dorsal displacement of Agouti expression, establishing that early embryonic Tbx15 expression in dorsolateral mesenchyme provides an instructional cue that sets the future positional identity of dorsal dermis and controls the dorsoventral pigmentation boundary.\",\n      \"method\": \"Targeted knockout allele, transplantation experiments, fate-mapping studies, embryonic expression analysis\",\n      \"journal\": \"PLoS biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal genetic confirmation (deletion + targeted allele), transplantation, and fate-mapping across multiple experiments in one rigorous study\",\n      \"pmids\": [\"14737183\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Tbx15 null mice display reduced proliferation of prehypertrophic chondrocytes and mesenchymal precursor cells, resulting in reduced bone size and altered bone shape, indicating Tbx15 controls cell number in skeletal progenitor populations during endochondral and intramembranous ossification.\",\n      \"method\": \"Tbx15 null mutant mouse analysis, histology, proliferation assays\",\n      \"journal\": \"Mechanisms of development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean loss-of-function mouse model with defined cellular proliferation phenotype across multiple skeletal compartments\",\n      \"pmids\": [\"15652702\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Tbx15 and Gli3 exhibit synergistic genetic interactions in scapular blade formation, and Tbx15 combined with Alx4 and Cart1 mutations indicates epistatic relationships in patterning the shoulder girdle progenitor cells.\",\n      \"method\": \"Double and triple mutant mouse genetic epistasis analysis, marker gene expression\",\n      \"journal\": \"Development (Cambridge, England)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis in compound mutants, single lab, multiple genotypes analyzed\",\n      \"pmids\": [\"15728667\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"TBX15 and TBX18 proteins homo- and heterodimerize, bind to various combinations of T half-sites, and repress transcription in a Groucho corepressor-dependent manner; functional domains for nuclear localization, DNA binding, and transcriptional modulation were characterized.\",\n      \"method\": \"In vitro DNA binding assays, transcriptional reporter (luciferase) assays, co-immunoprecipitation, domain mutagenesis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro biochemical characterization with multiple orthogonal methods (DNA binding, reporter assay, co-IP, domain mapping) in a single focused mechanistic study\",\n      \"pmids\": [\"17584735\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Human TBX15 loss-of-function mutations cause Cousin syndrome; mutant proteins with intact T-box could bind target DNA in vitro but contained a missense stretch directing them to early degradation, markedly reducing cellular protein levels.\",\n      \"method\": \"Human genetic analysis, in vitro DNA binding assay, protein stability/degradation assays\",\n      \"journal\": \"American journal of human genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro DNA binding confirmed, protein degradation demonstrated biochemically, human disease linkage confirming loss-of-function mechanism\",\n      \"pmids\": [\"19068278\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Ectopic Tbx6 expression in segmented paraxial mesoderm produces Tbx15 null-like phenotypes; in vitro luciferase assays support competition between Tbx6 and endogenous Tbx15 at shared T-box binding sites on target gene promoters.\",\n      \"method\": \"Transgenic misexpression mouse model, in vitro luciferase transcriptional assay\",\n      \"journal\": \"Developmental biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis via misexpression with in vitro transcriptional competition assay, single lab\",\n      \"pmids\": [\"20832395\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Overexpression of Tbx15 in 3T3-L1 preadipocytes impairs adipocyte differentiation, reduces triglyceride content, decreases basal lipogenic rate, increases lipolytic rate, reduces mitochondrial mass by 15%, reduces basal mitochondrial respiration by 28%, and reduces maximal respiratory capacity by 45%.\",\n      \"method\": \"Stable overexpression in 3T3-L1 cells, triglyceride assay, respirometry (mitochondrial function assays), lipogenesis/lipolysis assays\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — overexpression in cell culture with multiple quantitative functional readouts (respiration, lipogenesis, lipolysis, differentiation markers), single lab, orthogonal methods\",\n      \"pmids\": [\"21282637\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"PDX1 represses the TBX15 promoter in a methylation-dependent manner, establishing PDX1 as a transcriptional repressor of TBX15 acting through the differentially methylated distal promoter region.\",\n      \"method\": \"Promoter methylation analysis (pyrosequencing, bisulfite), luciferase reporter assay with PDX1\",\n      \"journal\": \"Epigenetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — reporter assay demonstrates PDX1 repression of TBX15 promoter, single lab, single method for mechanism\",\n      \"pmids\": [\"20962579\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"siRNA knockdown of Tbx15 in primary brown and inguinal (brite-competent) adipocyte precursors reduces expression of adipogenesis markers (PPARγ, aP2) and brown phenotypic markers (PRDM16, PGC-1α, UCP1), while having no effect on epididymal (non-brite-competent) white adipocytes, establishing Tbx15 as required for the brown/brite adipogenic program.\",\n      \"method\": \"siRNA knockdown in primary mouse adipocyte cultures, qPCR gene expression analysis\",\n      \"journal\": \"American journal of physiology. Endocrinology and metabolism\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — siRNA knockdown with clear cell-type-specific phenotype and multiple gene expression readouts, single lab\",\n      \"pmids\": [\"22912368\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"Ablation of Tbx15 in vivo decreases the number of glycolytic myofibers with a corresponding increase in oxidative fibers, slows myofiber contraction/relaxation, and reduces whole-body oxygen consumption; mechanistically, Tbx15 ablation activates AMPK signaling and decreases Igf2 expression.\",\n      \"method\": \"Conditional knockout mice, fiber-type immunostaining, metabolic phenotyping, contractility assays, Western blot (AMPK), qPCR (Igf2)\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean in vivo KO with multiple orthogonal readouts (fiber type, contractility, metabolic, signaling pathway), well-controlled study\",\n      \"pmids\": [\"26299309\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"TBX15 overexpression in thyroid cancer cells reduces apoptosis, decreases pro-apoptotic Bax, and increases anti-apoptotic Bcl2 and Bcl-XL; siRNA knockdown increases apoptosis, establishing an anti-apoptotic function for TBX15.\",\n      \"method\": \"Transfection/overexpression, siRNA knockdown, Western blot (Bax, Bcl2, Bcl-XL), apoptosis assay\",\n      \"journal\": \"Apoptosis : an international journal on programmed cell death\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — gain- and loss-of-function with consistent results, multiple apoptotic markers, single lab\",\n      \"pmids\": [\"26216026\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"NF-κBp65 directly binds to two functional NF-κB binding sites at positions -3302 and -3059 of the TBX15 gene, activating TBX15 expression in response to TNF-α; luciferase reporter assays and ChIP confirm direct NF-κB-mediated transcriptional regulation of TBX15.\",\n      \"method\": \"Luciferase reporter assay, ChIP assay, TNF-α/PMA-ionomycin stimulation, bisulfite sequencing\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP confirms direct binding, corroborated by reporter assay, two orthogonal methods, single lab\",\n      \"pmids\": [\"27327083\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Tbx15 expression is restricted to a glycolytic subpopulation within white adipose tissue, and overexpression of Tbx15 is sufficient to shift adipocyte metabolism toward glycolysis and away from oxidative metabolism in cultured adipocytes.\",\n      \"method\": \"Single-depot subpopulation isolation, metabolic profiling (ECAR/OCR), Tbx15 overexpression in cultured adipocytes\",\n      \"journal\": \"Diabetes\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional overexpression experiment with metabolic readouts, combined with subpopulation characterization, single lab\",\n      \"pmids\": [\"28847884\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"TBX15 directly binds to a key region in the Prdm16 promoter (identified by ChIP), transcriptionally regulating Prdm16, the master gene for adipocyte thermogenesis; adipose-specific Tbx15 knockout impairs adipocyte browning in inguinal fat upon cold exposure and β3-adrenergic stimulation.\",\n      \"method\": \"Adipose-specific conditional knockout (adiponectin-Cre), ChIP assay on Prdm16 promoter, cold-exposure and β3-agonist challenge, metabolic phenotyping\",\n      \"journal\": \"Molecular metabolism\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — conditional KO with specific physiological phenotype, combined with ChIP demonstrating direct promoter binding, two orthogonal methods\",\n      \"pmids\": [\"31352005\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"TBX15 transcriptionally activates miR-152 expression, which in turn targets KIF2C; TBX15/miR-152 overexpression suppresses autophagy and glycolysis in breast cancer cells; KIF2C directly binds PKM2 and prevents PKM2 ubiquitination, stabilizing it and promoting doxorubicin resistance.\",\n      \"method\": \"Luciferase reporter assay, co-immunoprecipitation (KIF2C-PKM2), ECAR/OCR assays, ubiquitination assay, Western blot\",\n      \"journal\": \"Cancer cell international\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reporter assay + co-IP for pathway placement, ubiquitination assay for mechanism, single lab, multiple methods\",\n      \"pmids\": [\"34663310\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"TBX15 knockdown in human primary preadipocytes changes expression of 130 co-expression network genes including key adipose transcription factors PPARG and KLF15, establishing TBX15 as a trans-regulator of an abdominal obesity-associated adipose gene network.\",\n      \"method\": \"siRNA knockdown in human primary preadipocytes, RNA-seq gene expression profiling\",\n      \"journal\": \"Genome medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — loss-of-function knockdown with transcriptome-wide readout in human primary cells, single lab\",\n      \"pmids\": [\"34340684\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"TBX15 binds to the promoter region of ADAMTS2 and activates its promoter activity, as demonstrated by cellular co-transfection and ChIP assays; TBX15 and ADAMTS2 co-localize in posterior palatal mesenchymal cells at E13.5.\",\n      \"method\": \"ChIP assay, co-transfection reporter assay, immunofluorescence co-localization\",\n      \"journal\": \"Human mutation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP and reporter assay confirm direct promoter binding and activation, single lab, two orthogonal methods\",\n      \"pmids\": [\"36124393\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"TBX15 silencing in glioma cells inhibits proliferation, migration, and invasion, and reduces macrophage recruitment and M2 polarization; TBX15 transcriptionally activates TXNDC5, and rescue assays confirm that TBX15's effects in glioma depend on TXNDC5.\",\n      \"method\": \"shRNA silencing, rescue assay with TXNDC5 overexpression, in vitro migration/invasion/proliferation assays, in vivo tumor model\",\n      \"journal\": \"iScience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — loss-of-function with rescue establishing epistasis, in vitro and in vivo, single lab\",\n      \"pmids\": [\"38327797\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"TBX15 ChIP-sequencing in mouse 3T3-L1 preadipocytes overexpressing TBX15 identified a set of 52 directly bound target genes enriched for B- and T-cell receptor signalling, JAK-STAT signalling, and haematopoietic cell lineage pathways in adipose tissue.\",\n      \"method\": \"ChIP-sequencing in 3T3-L1 preadipocytes, RNA-seq in knockout adipose tissue, integration of datasets\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP-seq identifies direct binding targets, integrated with transcriptomic data from KO, preprint not yet peer-reviewed\",\n      \"pmids\": [],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"A truncating TBX15 variant (p.Gln411Ter) causes aberrant cytoplasmic mis-localization of the mutant TBX15 protein and significantly reduced transcriptional activity; TBX15 is expressed in a specific mesenchymal cell population during palatogenesis and co-localizes with osteogenic markers, implicating it in intramembranous bone formation of the palate.\",\n      \"method\": \"Protein localization assay, transcriptional activity assay, snRNA-seq, immunofluorescence\",\n      \"journal\": \"International dental journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional characterization of missense variant with localization and transcriptional assays, snRNA-seq for expression context, single lab\",\n      \"pmids\": [\"41904889\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"TBX15 is a T-box transcription factor that homodimerizes and heterodimerizes with TBX18, binds T half-site combinations in DNA, and represses transcription via Groucho corepressors; it directly activates target gene promoters (PRDM16, ADAMTS2, TXNDC5) through ChIP-confirmed binding, is itself transcriptionally regulated by NF-κB and repressed by PDX1 in a methylation-dependent manner, and functions in mesenchymal progenitor proliferation (skeletal development), dorsoventral dermis patterning (via Agouti regulation), glycolytic fiber identity in skeletal muscle (through AMPK/IGF2), and adipocyte thermogenesis/browning (through direct regulation of PRDM16), with loss-of-function in humans causing Cousin syndrome.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"TBX15 is a T-box transcription factor that patterns mesenchymal progenitor populations during skeletal and dermal development and later governs metabolic identity in adipose tissue and muscle [#0, #1, #13]. It homo- and heterodimerizes with TBX18, binds combinations of T half-sites, and represses transcription through Groucho corepressors, with separable domains for nuclear localization, DNA binding, and transcriptional modulation [#3]. In development, TBX15 expression in dorsolateral mesenchyme sets dorsoventral positional identity of the dermis by constraining Agouti expression, drives proliferation of skeletal progenitors and prehypertrophic chondrocytes to control bone size and shape, and acts within genetic networks shaping the shoulder girdle [#0, #1, #2]. It functions in part by occupying T-box sites that are subject to competition with other T-box proteins such as TBX6 [#5]. Beyond repression, TBX15 directly activates target promoters confirmed by ChIP, including PRDM16 to drive the brown/brite adipocyte thermogenic program, ADAMTS2 in palatal mesenchyme, and TXNDC5 in glioma [#13, #16, #17]. In metabolism, TBX15 marks and promotes a glycolytic state—specifying glycolytic myofibers via AMPK/IGF2 signaling and shifting adipocyte metabolism toward glycolysis—while regulating an adipose gene network including PPARG and KLF15 [#9, #12, #15]. TBX15 transcription is itself controlled, being activated by NF-\\u03baBp65 in response to TNF-\\u03b1 and repressed by PDX1 in a promoter-methylation-dependent manner [#11, #7]. Human loss-of-function mutations cause Cousin syndrome through protein destabilization or cytoplasmic mislocalization that depletes functional TBX15 [#4, #19].\",\n  \"teleology\": [\n    {\n      \"year\": 2004,\n      \"claim\": \"Established that TBX15 provides an early positional cue, answering how dorsoventral dermal and pigmentation boundaries are set in the embryo.\",\n      \"evidence\": \"Targeted knockout, transplantation, and fate-mapping in mouse embryos showing dorsal displacement of Agouti expression\",\n      \"pmids\": [\"14737183\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct transcriptional targets mediating dermal patterning not identified\", \"Whether Agouti regulation is direct or indirect unresolved\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Defined TBX15 as a controller of progenitor cell number, showing its developmental role operates through proliferation rather than fate alone.\",\n      \"evidence\": \"Tbx15-null mouse histology and proliferation assays across skeletal compartments\",\n      \"pmids\": [\"15652702\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Downstream cell-cycle targets not identified\", \"Mechanism linking TBX15 to proliferation unknown\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Placed TBX15 within a genetic patterning network for the shoulder girdle, defining epistatic partners.\",\n      \"evidence\": \"Compound mutant genetic epistasis with Gli3, Alx4, and Cart1 in mice\",\n      \"pmids\": [\"15728667\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Genetic interactions do not establish direct molecular relationships\", \"No shared target genes defined\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Resolved the biochemical mode of action: how TBX15 binds DNA and represses transcription.\",\n      \"evidence\": \"In vitro DNA binding, luciferase reporters, co-IP, and domain mutagenesis showing homo/heterodimerization with TBX18 and Groucho-dependent repression\",\n      \"pmids\": [\"17584735\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Endogenous genomic binding sites not mapped\", \"Repression versus activation context not reconciled\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Linked TBX15 to human disease and clarified the loss-of-function mechanism at the protein level.\",\n      \"evidence\": \"Human genetic analysis of Cousin syndrome plus in vitro DNA binding and protein degradation assays\",\n      \"pmids\": [\"19068278\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Tissue-specific consequences of protein loss not detailed\", \"Target genes deregulated in patients unknown\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Showed TBX15 competes with other T-box factors at shared sites, explaining how mesoderm positional information is encoded.\",\n      \"evidence\": \"Tbx6 misexpression transgenic mice and in vitro luciferase competition assays\",\n      \"pmids\": [\"20832395\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Competition shown in vitro; endogenous co-occupancy not demonstrated\", \"Specific target promoters limited\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Opened the metabolic dimension of TBX15, showing it suppresses adipocyte differentiation and mitochondrial function.\",\n      \"evidence\": \"Stable overexpression in 3T3-L1 cells with respirometry, lipogenesis/lipolysis, and triglyceride assays\",\n      \"pmids\": [\"21282637\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Overexpression model; physiological relevance addressed later\", \"Direct transcriptional targets not defined here\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Identified an upstream epigenetic repressor of TBX15, connecting its promoter methylation to PDX1.\",\n      \"evidence\": \"Bisulfite/pyrosequencing methylation analysis and PDX1 luciferase reporter assays\",\n      \"pmids\": [\"20962579\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single method for mechanism\", \"Physiological context of PDX1 repression not established\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Refined TBX15's adipose role by showing it is required for the brown/brite adipogenic program in a cell-type-specific manner.\",\n      \"evidence\": \"siRNA knockdown in primary brown, inguinal, and epididymal adipocyte precursors with qPCR\",\n      \"pmids\": [\"22912368\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct versus indirect regulation of brown markers unresolved at this stage\", \"Knockdown only\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Established TBX15 as a determinant of glycolytic myofiber identity and whole-body energetics via AMPK/IGF2.\",\n      \"evidence\": \"Conditional knockout mice with fiber-type immunostaining, contractility, metabolic phenotyping, AMPK Western blot, and Igf2 qPCR\",\n      \"pmids\": [\"26299309\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether Igf2 is a direct TBX15 target not shown\", \"Mechanism of AMPK activation not defined\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Extended TBX15 to cancer cell survival, defining an anti-apoptotic function.\",\n      \"evidence\": \"Overexpression and siRNA knockdown in thyroid cancer cells with Bax/Bcl2/Bcl-XL Western blot and apoptosis assays\",\n      \"pmids\": [\"26216026\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct transcriptional targets of apoptosis regulation not identified\", \"Single lab, single cancer type\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Identified a direct inflammatory upstream input, showing NF-\\u03baB activates TBX15 transcription.\",\n      \"evidence\": \"ChIP and luciferase reporter assays with TNF-\\u03b1 stimulation defining two functional NF-\\u03baB sites\",\n      \"pmids\": [\"27327083\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Physiological significance of TNF-\\u03b1-driven TBX15 induction unclear\", \"Downstream consequences not traced\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Showed TBX15 is sufficient to impose glycolytic metabolism in adipocytes, linking its expression domain to metabolic phenotype.\",\n      \"evidence\": \"Subpopulation isolation, ECAR/OCR metabolic profiling, and overexpression in cultured adipocytes\",\n      \"pmids\": [\"28847884\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct metabolic gene targets not defined\", \"Overexpression-based sufficiency\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Provided the direct molecular link from TBX15 to thermogenesis by identifying PRDM16 as a directly bound, regulated target.\",\n      \"evidence\": \"Adipose-specific conditional knockout with ChIP on the Prdm16 promoter and cold/\\u03b23-agonist challenge\",\n      \"pmids\": [\"31352005\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Reconciliation of activation (PRDM16) with prior Groucho-dependent repression not addressed\", \"Cofactors at PRDM16 promoter unknown\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Defined a TBX15-driven regulatory cascade controlling autophagy, glycolysis, and chemoresistance in breast cancer.\",\n      \"evidence\": \"Luciferase reporter, KIF2C-PKM2 co-IP, ubiquitination, and ECAR/OCR assays placing TBX15 upstream of miR-152/KIF2C/PKM2\",\n      \"pmids\": [\"34663310\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Multi-step pathway from a single lab\", \"Direct binding of TBX15 to miR-152 locus not confirmed by ChIP\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Positioned TBX15 as a trans-regulator of a human adipose gene network relevant to body-fat distribution.\",\n      \"evidence\": \"siRNA knockdown in human primary preadipocytes with RNA-seq identifying 130 network genes including PPARG and KLF15\",\n      \"pmids\": [\"34340684\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct versus indirect targets within the network not distinguished\", \"No ChIP in human cells\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Identified ADAMTS2 as a direct TBX15 target in palatal mesenchyme, extending its developmental gene regulation.\",\n      \"evidence\": \"ChIP, co-transfection reporter, and immunofluorescence co-localization at E13.5\",\n      \"pmids\": [\"36124393\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional consequence of ADAMTS2 activation in palatogenesis not tested\", \"Single lab\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Established a TBX15\\u2192TXNDC5 axis driving glioma malignancy and tumor immune microenvironment remodeling.\",\n      \"evidence\": \"shRNA silencing with TXNDC5 rescue, in vitro invasion/migration assays, and in vivo tumor model\",\n      \"pmids\": [\"38327797\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct binding of TBX15 to TXNDC5 promoter via ChIP not shown\", \"Mechanism of macrophage M2 polarization control indirect\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Genome-wide mapping of TBX15 binding sites in preadipocytes, defining a direct target set with unexpected immune-pathway enrichment.\",\n      \"evidence\": \"ChIP-sequencing in TBX15-overexpressing 3T3-L1 cells integrated with knockout adipose RNA-seq (preprint)\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Preprint, not yet peer-reviewed\", \"Overexpression context may bias binding\", \"Functional validation of immune-pathway targets pending\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Linked a new truncating TBX15 variant to palatal bone formation defects through protein mislocalization, extending the loss-of-function spectrum.\",\n      \"evidence\": \"Localization and transcriptional activity assays of p.Gln411Ter variant with snRNA-seq and immunofluorescence\",\n      \"pmids\": [\"41904889\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct osteogenic targets in palate not identified\", \"Single variant, single lab\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How TBX15 switches between Groucho-dependent repression and direct promoter activation, and which cofactors dictate target choice across developmental versus metabolic contexts, remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model of context-dependent cofactor recruitment\", \"Genome-wide direct targets in vivo not consolidated across tissues\", \"Mechanistic basis for activation versus repression unknown\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140110\", \"supporting_discovery_ids\": [3, 13, 16, 17]},\n      {\"term_id\": \"GO:0003677\", \"supporting_discovery_ids\": [3, 4]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [3, 19]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [0, 1, 16]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [3, 13]},\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [9, 12, 13]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\n      \"TBX18\",\n      \"TLE\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":8,"faith_pct":87.5}}