{"gene":"BRDT","run_date":"2026-06-09T22:02:45","timeline":{"discoveries":[{"year":2003,"finding":"BRDT specifically binds hyperacetylated histone H4 tail in an acetylation-dependent manner requiring the integrity of both bromodomains, and induces large-scale chromatin reorganization in an ATP-independent manner in somatic cells only after induction of histone hyperacetylation; both bromodomains and flanking regions are indispensable for this remodelling activity.","method":"In vitro chromatin remodeling assay on isolated nuclei, bromodomain mutagenesis, ectopic expression in somatic cells with TSA treatment","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution assay with mutagenesis of functional domains, multiple orthogonal methods in one study","pmids":["12861021"],"is_preprint":false},{"year":2007,"finding":"The first bromodomain (BD1) of Brdt is essential for male germ cell differentiation in vivo; mice lacking only BD1 are sterile with aberrant spermatid morphogenesis and lack peri-nuclear heterochromatin foci. Brdt protein (but not BrdtΔBD1) associates with the promoter of histone H1t, and BD1 deletion leads to 3-fold increased H1t levels.","method":"Targeted mutagenesis (deletion of BD1 in mice), chromatin immunoprecipitation (ChIP), quantitative RT-PCR, immunostaining","journal":"Development (Cambridge, England)","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean genetic KO with defined phenotype, ChIP confirming promoter occupancy, replicated across multiple methods","pmids":["17728347"],"is_preprint":false},{"year":2012,"finding":"JQ1, a small-molecule inhibitor, occupies the BRDT acetyl-lysine binding pocket and prevents recognition of acetylated histone H4, as confirmed by crystallography. In mice, JQ1 reduces seminiferous tubule area, testis size, and spermatozoa number and motility, causing a complete and reversible contraceptive effect at the spermatocyte and round spermatid stages.","method":"Biochemical binding assay, X-ray crystallography of JQ1-BRDT complex, in vivo mouse treatment","journal":"Cell","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure plus in vivo functional validation, replicated across biochemical and animal models","pmids":["22901802"],"is_preprint":false},{"year":2012,"finding":"Brdt acts as a master regulator of meiotic and post-meiotic gene expression programs; its first bromodomain directs genome-wide replacement of histones by transition proteins during global chromatin hyperacetylation at post-meiotic stages, while other domains drive a spermatogenic transcriptional program at meiotic stages.","method":"Genetic mouse models (Brdt knockout and BD1 deletion), genome-wide transcriptional analysis, ChIP, immunostaining","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean genetic models with defined stage-specific phenotypes, genome-wide chromatin and transcriptional analyses","pmids":["22922464"],"is_preprint":false},{"year":2012,"finding":"Brdt colocalizes with acetylated H4 in elongating spermatids and induces acetylation-dependent but ATP-independent chromatin reorganization in round spermatids. Brdt interacts with Smarce1 (a SWI/SNF family member) via its N-terminus, and this interaction increases upon histone hyperacetylation both in vitro and in vivo.","method":"Immunocytochemistry, in vitro chromatin remodeling assay, co-immunoprecipitation, pulldown assay","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP and in vitro remodeling assay in single lab, two orthogonal methods","pmids":["22215678"],"is_preprint":false},{"year":2012,"finding":"BRDT forms a complex with multiple spliceosome components (Srsf2, Ddx5, Hnrnpk, Tardbp) and is required for mRNA splicing and 3'-UTR truncation in round spermatids. Loss of BD1 leads to longer 3'-UTRs and reduced protein levels of splicing factors, and BD1 is essential for these functions.","method":"Transcriptome analysis of Brdt(ΔBD1/ΔBD1) vs control round spermatids, co-immunoprecipitation of BRDT with spliceosome components, RNA-seq","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP with multiple spliceosome components plus transcriptome-level functional validation in genetic model","pmids":["22570411"],"is_preprint":false},{"year":2015,"finding":"BRDT forms complexes with HDAC1, PRMT5, and TRIM28 in round spermatids, as shown by affinity purification of FLAG-tagged BRDT and co-IP from testicular extracts. These complexes bind the H1t promoter, and this binding is lost in Brdt(ΔBD1) mutants, correlating with elevated H1t expression, indicating a role for BRDT-containing complexes in transcriptional repression.","method":"Affinity purification of FLAG-tagged BRDT, co-immunoprecipitation from testicular extracts, ChIP, immunofluorescence","journal":"Journal of cellular biochemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP from testicular extracts plus ChIP validation, single lab","pmids":["26565999"],"is_preprint":false},{"year":2016,"finding":"BRDT interacts with nucleosomes through its first bromodomain (BD1) but not second bromodomain (BD2); acetylated histone recognition by BD1 is complemented by a bromodomain-DNA interaction, which together enhance BRDT's nucleosome binding affinity, specificity, and localization to acetylated chromatin in cells. Conservation of DNA binding in BRD2, BRD3, and BRD4 bromodomains suggests this is a shared BET mechanism.","method":"NMR, biochemical nucleosome binding assay with site-specifically acetylated nucleosomes, cell-based chromatin localization assay","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 1 / Strong — NMR structural characterization plus biochemical reconstitution with site-specifically acetylated nucleosomes and cell-based validation","pmids":["27991587"],"is_preprint":false},{"year":2018,"finding":"Complete loss of BRDT disrupts meiotic sex chromosome inactivation in spermatocytes, affects synapsis and silencing of the X and Y chromosomes, disrupts global chromatin organization and histone modifications at the synaptonemal complex, and alters the homeostasis of crossover formation and localization during pachynema, establishing BRDT as an essential regulator of meiotic chromatin organization.","method":"Complete Brdt knockout mouse model, immunofluorescence, ChIP, FISH, analysis of meiotic progression","journal":"PLoS genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean genetic KO with multiple defined meiotic phenotypes assessed by orthogonal methods","pmids":["29513658"],"is_preprint":false},{"year":2020,"finding":"PHF7 acts as an E3 ubiquitin ligase for histone H3K14 in post-meiotic spermatids, and its ubiquitin ligase activity stabilizes BRDT by attenuating ubiquitination of BRDT itself, thereby enabling histone-to-protamine exchange. Loss of PHF7 E3 ligase activity leads to dysregulation of BRDT in early condensing spermatids and defects in histone-to-protamine exchange.","method":"Phf7-deficient mice, Phf7 C160A knockin mice (impaired E3 ligase), biochemical ubiquitination assay, co-immunoprecipitation","journal":"Cell reports","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic knockin of catalytic mutant plus biochemical ubiquitination assay and rescue experiments, multiple orthogonal methods","pmids":["32726616"],"is_preprint":false},{"year":2011,"finding":"The first bromodomain of Brdt is required for chromocenter integrity in spermatids; Brdt(ΔBD1/ΔBD1) mutants exhibit fragmented chromocenters with increased HP1α levels and ectopic H1fnt localization. Brdt protein is normally excluded from the chromocenter and appears to separate Sirt1 from contact with the chromocenter, a spatial relationship lost upon BD1 deletion.","method":"Brdt(ΔBD1/ΔBD1) mouse model, immunofluorescence microscopy, co-localization analysis","journal":"Developmental biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean genetic model with defined structural phenotype, immunofluorescence localization data, single lab","pmids":["22020252"],"is_preprint":false},{"year":2021,"finding":"In esophageal squamous cell carcinoma (ESCC), BRDT colocalizes and interacts with ΔNp63 at super-enhancers to drive transcriptional activation of ΔNp63 target genes (including KRT14, FAT2, PTHLH) that are involved in squamous cell identity; BRDT promotes cell migration but is dispensable for proliferation in this context. BET PROTAC MZ1 preferentially degrades BRDT over BRD2, BRD3, and BRD4.","method":"ChIP-seq, genome-wide chromatin interaction studies, transcriptome analysis, co-immunoprecipitation, CRISPR/shRNA knockdown","journal":"Cell death and differentiation","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple genome-wide and biochemical methods in single lab, co-localization and interaction confirmed","pmids":["33658703"],"is_preprint":false},{"year":2021,"finding":"CDD-1102 is a selective BRDT-BD2 inhibitor with low nanomolar potency and >1,000-fold selectivity over BRDT-BD1. Co-crystal structures of BRDT-BD2 with CDD-1102 and CDD-1302 (at 2.27 and 1.90 Å resolution) reveal BRDT-BD2-specific contacts explaining their affinity and selectivity.","method":"DNA-encoded chemical library screening, AlphaScreen competition assay, X-ray crystallography of BRDT-BD2 inhibitor complexes, BROMOscan profiling","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structures at high resolution plus biochemical selectivity profiling using orthogonal methods","pmids":["33637650"],"is_preprint":false},{"year":2020,"finding":"In renal cell carcinoma cells, BRDT interacts with eIF4EBP1 (identified by immunoprecipitation and mass spectrometry), and BRDT inhibition or knockdown suppresses eIF4EBP1 protein expression and c-myc transcription; BRDT regulates c-myc promoter activity, and eIF4EBP1 overexpression partially rescues the growth inhibition caused by BRDT inhibition.","method":"Co-immunoprecipitation, mass spectrometry, siRNA knockdown, luciferase reporter assay, in vivo xenograft","journal":"Oncology reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP/MS identification plus functional rescue experiments, single lab","pmids":["33125143"],"is_preprint":false},{"year":2017,"finding":"A homozygous BRDT mutation (p.G928D) in the P-TEFb binding domain causes acephalic spermatozoa and mis-regulation of 899 genes compared to wild-type BRDT-expressing cells, with upregulated genes enriched in intracellular transport, RNA splicing, cell cycle, and DNA metabolic processes.","method":"Whole-exome sequencing, RNA-sequencing of mutant vs wild-type cells, Gene Ontology analysis","journal":"Oncotarget","confidence":"Low","confidence_rationale":"Tier 3 / Weak — patient mutation identification with transcriptome analysis, no direct biochemical confirmation of P-TEFb interaction disruption","pmids":["28199965"],"is_preprint":false},{"year":2023,"finding":"During meiotic prophase I, RNA Pol II is loaded and maintained in a paused state early during prophase I; in later stages, paused Pol II is released in a coordinated transcriptional burst mediated by both A-MYB and BRDT, resulting in approximately 3-fold increase in transcription at genes required for meiotic progression.","method":"Genome-wide chromatin accessibility (ATAC-seq), nascent transcription measurement (GRO-seq), processed mRNA profiling in staged spermatocytes","journal":"Nature communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple genome-wide assays establishing Pol II pause-release coordination with BRDT, single lab","pmids":["36990976"],"is_preprint":false},{"year":2022,"finding":"Bivalent BET inhibitors show increased potency and selectivity for BRDT over BRD4; X-ray crystallography and solution studies reveal that bivalent inhibitors induce unique dimeric structural states of BRDT that differ from those of BRD4, explaining the differential selectivity through protein conformational plasticity.","method":"X-ray crystallography, biophysical solution studies, cell-based activity assays, structure-activity relationship analysis","journal":"Journal of medicinal chemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — crystal structures with functional validation showing unique BRDT conformational states, multiple orthogonal structural and biophysical methods","pmids":["35867655"],"is_preprint":false}],"current_model":"BRDT is a testis-specific BET family double-bromodomain protein that functions as a master epigenetic regulator of spermatogenesis: its first bromodomain (BD1) directly recognizes acetylated histone H4 and, complemented by a bromodomain-DNA interaction, directs genome-wide histone replacement by transition proteins in post-meiotic spermatids; it also drives stage-specific transcriptional programs (including Pol II pause release in meiosis in concert with A-MYB), represses genes via complexes with HDAC1/PRMT5/TRIM28, regulates mRNA splicing and 3'-UTR processing through interactions with spliceosome components, controls meiotic sex chromosome inactivation and crossover formation, and is itself stabilized by PHF7-mediated ubiquitination of histone H3K14 which attenuates BRDT ubiquitination—all of which are essential for male fertility."},"narrative":{"mechanistic_narrative":"BRDT is a testis-specific BET-family double-bromodomain protein that serves as a master epigenetic regulator of meiotic and post-meiotic gene expression and chromatin remodeling during spermatogenesis [PMID:22922464]. Its first bromodomain (BD1) recognizes hyperacetylated histone H4 in an acetylation-dependent manner and drives large-scale, ATP-independent chromatin reorganization [PMID:12861021]; BD1-mediated acetyl-lysine recognition is complemented by a direct bromodomain–DNA contact that enhances nucleosome binding affinity, specificity, and localization to acetylated chromatin [PMID:27991587]. Through BD1 this activity directs the genome-wide replacement of histones by transition proteins during the global hyperacetylation of post-meiotic spermatids [PMID:22922464], and BD1 is required in vivo for spermatid morphogenesis, peri-nuclear heterochromatin foci, and chromocenter integrity [PMID:17728347, PMID:22020252]. BRDT also assembles into repressive complexes with HDAC1, PRMT5, and TRIM28 that occupy the H1t promoter, with BD1 loss derepressing H1t [PMID:26565999, PMID:17728347], and it partners with spliceosome components (Srsf2, Ddx5, Hnrnpk, Tardbp) to control mRNA splicing and 3'-UTR truncation in round spermatids [PMID:22570411]. In meiosis BRDT cooperates with A-MYB to release paused RNA Pol II in a coordinated transcriptional burst at meiotic genes [PMID:36990976] and is required for meiotic sex chromosome inactivation, synapsis, and crossover homeostasis [PMID:29513658]. BRDT protein stability is controlled by PHF7, an E3 ligase for histone H3K14 that attenuates BRDT ubiquitination to enable histone-to-protamine exchange [PMID:32726616]. The acetyl-lysine pocket is druggable: JQ1 occupies it and produces a reversible contraceptive effect in mice [PMID:22901802], establishing BRDT as a male contraceptive target. Beyond spermatogenesis, BRDT has been implicated in cancer contexts including ΔNp63-driven super-enhancer transcription in esophageal squamous cell carcinoma and c-myc/eIF4EBP1 regulation in renal cell carcinoma [PMID:33658703, PMID:33125143].","teleology":[{"year":2003,"claim":"Established the core biochemical activity of BRDT—recognition of hyperacetylated H4 and induction of chromatin compaction—answering whether BRDT reads acetyl marks and reorganizes chromatin.","evidence":"In vitro chromatin remodeling on isolated nuclei with bromodomain mutagenesis and ectopic expression in TSA-treated somatic cells","pmids":["12861021"],"confidence":"High","gaps":["Did not establish the in vivo germ-cell substrate or downstream effectors","ATP-independent mechanism of compaction not resolved structurally"]},{"year":2007,"claim":"Demonstrated that BD1 is genetically essential for spermatid differentiation in vivo and that BRDT occupies a specific target promoter (H1t), linking the biochemical reader function to fertility.","evidence":"BD1-deletion mouse, ChIP, qRT-PCR, immunostaining","pmids":["17728347"],"confidence":"High","gaps":["Did not define the full repertoire of BRDT-bound promoters","Mechanism of H1t repression not yet defined"]},{"year":2011,"claim":"Resolved BD1's structural role in spermatid nuclear architecture, showing BD1 is required for chromocenter integrity and spatial exclusion of HP1α and Sirt1.","evidence":"BD1-deletion mouse with immunofluorescence and colocalization analysis","pmids":["22020252"],"confidence":"Medium","gaps":["Single lab, descriptive localization","Causal link between chromocenter defect and infertility not dissected"]},{"year":2012,"claim":"Partitioned BRDT function across spermatogenic stages, establishing it as a master regulator that uses BD1 for post-meiotic histone replacement and other domains for meiotic transcription, and identified its physical partners.","evidence":"Brdt knockout and BD1-deletion mice with genome-wide transcriptional/ChIP analysis; co-IP with Smarce1 and with spliceosome components (Srsf2, Ddx5, Hnrnpk, Tardbp); JQ1 crystal structure with in vivo contraception","pmids":["22922464","22215678","22570411","22901802"],"confidence":"High","gaps":["Mechanism by which BD1 directs transition-protein exchange not biochemically reconstituted","Splicing/3'-UTR control mechanism not resolved at single-gene level"]},{"year":2015,"claim":"Defined BRDT's repressive complex composition, showing it assembles with HDAC1, PRMT5, and TRIM28 at the H1t promoter to enforce gene silencing.","evidence":"FLAG-BRDT affinity purification, co-IP from testicular extracts, ChIP, immunofluorescence","pmids":["26565999"],"confidence":"Medium","gaps":["Stoichiometry and assembly order of the complex unknown","Single lab; complex not structurally characterized"]},{"year":2016,"claim":"Explained how BRDT achieves chromatin specificity, showing BD1 recognition of acetyl-lysine is complemented by a bromodomain–DNA interaction that enhances nucleosome binding.","evidence":"NMR, biochemical binding with site-specifically acetylated nucleosomes, cell-based localization","pmids":["27991587"],"confidence":"High","gaps":["DNA-binding contribution to in vivo histone replacement not genetically tested","BD2 functional role left undefined"]},{"year":2018,"claim":"Extended BRDT function to meiotic chromosome biology, establishing it as essential for meiotic sex chromosome inactivation, synapsis, and crossover homeostasis.","evidence":"Complete Brdt knockout mouse, immunofluorescence, ChIP, FISH, meiotic progression analysis","pmids":["29513658"],"confidence":"High","gaps":["Molecular targets mediating MSCI and crossover control not identified","Direct chromatin mechanism at the synaptonemal complex unresolved"]},{"year":2020,"claim":"Identified an upstream regulator of BRDT stability, showing PHF7-mediated H3K14 ubiquitination attenuates BRDT ubiquitination to permit histone-to-protamine exchange.","evidence":"Phf7-null and Phf7 C160A catalytic-mutant knockin mice, in vitro ubiquitination assay, co-IP","pmids":["32726616"],"confidence":"High","gaps":["The E3 ligase ubiquitinating BRDT not identified","How H3K14ub mechanistically shields BRDT from degradation unknown"]},{"year":2023,"claim":"Placed BRDT in the meiotic transcriptional-burst pathway, showing it acts with A-MYB to release paused Pol II at meiotic genes.","evidence":"ATAC-seq, GRO-seq, and processed-mRNA profiling in staged spermatocytes","pmids":["36990976"],"confidence":"Medium","gaps":["Direct biochemical coupling of BRDT to P-TEFb/pause-release machinery not shown","Single lab"]},{"year":2021,"claim":"Showed BRDT can be co-opted in cancer, acting at ΔNp63 super-enhancers in ESCC and regulating c-myc/eIF4EBP1 in renal cell carcinoma, while advancing selective chemical tools.","evidence":"ChIP-seq, chromatin interaction studies, co-IP/MS, knockdown and rescue in tumor cells; selective BRDT-BD2 inhibitor co-crystal structures","pmids":["33658703","33125143","33637650"],"confidence":"Medium","gaps":["Physiological relevance of somatic BRDT expression unclear","Direct vs indirect c-myc regulation not fully separated"]},{"year":2022,"claim":"Demonstrated BRDT conformational plasticity exploitable for selectivity, with bivalent inhibitors inducing unique dimeric states distinct from BRD4.","evidence":"X-ray crystallography, solution biophysics, cell-based assays, SAR","pmids":["35867655"],"confidence":"High","gaps":["Functional consequence of induced BRDT dimerization in cells unknown","Relevance to native BRDT oligomeric state not established"]},{"year":null,"claim":"How BRDT mechanistically converts acetyl-histone recognition into directed transition-protein/protamine exchange, and how its meiotic and post-meiotic roles are temporally switched, remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No reconstituted system couples BD1 reading to histone-to-protamine exchange","Domain-level switch between meiotic transcription and post-meiotic remodeling undefined","Direct enzymatic partners executing chromatin reorganization unidentified"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0042393","term_label":"histone binding","supporting_discovery_ids":[0,1,2,7]},{"term_id":"GO:0003677","term_label":"DNA binding","supporting_discovery_ids":[7]},{"term_id":"GO:0140110","term_label":"transcription regulator activity","supporting_discovery_ids":[3,6,11,15]},{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[0,4]}],"localization":[{"term_id":"GO:0000228","term_label":"nuclear chromosome","supporting_discovery_ids":[1,8,10]},{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0,4]}],"pathway":[{"term_id":"R-HSA-4839726","term_label":"Chromatin organization","supporting_discovery_ids":[0,3,7]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[3,6,15]},{"term_id":"R-HSA-1474165","term_label":"Reproduction","supporting_discovery_ids":[1,3,8]},{"term_id":"R-HSA-8953854","term_label":"Metabolism of RNA","supporting_discovery_ids":[5]}],"complexes":["BRDT-HDAC1-PRMT5-TRIM28 repressive complex","BRDT-spliceosome complex"],"partners":["SMARCE1","HDAC1","PRMT5","TRIM28","SRSF2","DDX5","HNRNPK","PHF7"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q58F21","full_name":"Bromodomain testis-specific protein","aliases":["Cancer/testis antigen 9","CT9","RING3-like protein"],"length_aa":947,"mass_kda":108.0,"function":"Testis-specific chromatin protein that specifically binds histone H4 acetylated at 'Lys-5' and 'Lys-8' (H4K5ac and H4K8ac, respectively) and plays a key role in spermatogenesis (PubMed:22464331, PubMed:22901802). Required in late pachytene spermatocytes: plays a role in meiotic and post-meiotic cells by binding to acetylated histones at the promoter of specific meiotic and post-meiotic genes, facilitating their activation at the appropriate time (PubMed:22901802). In the post-meiotic phase of spermatogenesis, binds to hyperacetylated histones and participates in their general removal from DNA (PubMed:22901802). Also recognizes and binds a subset of butyrylated histones: able to bind histone H4 butyrylated at 'Lys-8' (H4K8ac), while it is not able to bind H4 butyrylated at 'Lys-5' (H4K5ac) (By similarity). Also acts as a component of the splicing machinery in pachytene spermatocytes and round spermatids and participates in 3'-UTR truncation of specific mRNAs in post-meiotic spermatids (By similarity). Required for chromocenter organization, a structure comprised of peri-centromeric heterochromatin","subcellular_location":"Nucleus","url":"https://www.uniprot.org/uniprotkb/Q58F21/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/BRDT","classification":"Not Classified","n_dependent_lines":2,"n_total_lines":1208,"dependency_fraction":0.0016556291390728477},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/BRDT","total_profiled":1310},"omim":[{"mim_id":"620057","title":"PHD FINGER PROTEIN 7; PHF7","url":"https://www.omim.org/entry/620057"},{"mim_id":"617644","title":"SPERMATOGENIC FAILURE 21; SPGF21","url":"https://www.omim.org/entry/617644"},{"mim_id":"616729","title":"OLFACTORY RECEPTOR, FAMILY 2, SUBFAMILY W, MEMBER 3; OR2W3","url":"https://www.omim.org/entry/616729"},{"mim_id":"607798","title":"TATA BOX-BINDING PROTEIN-ASSOCIATED FACTOR 1-LIKE; TAF1L","url":"https://www.omim.org/entry/607798"},{"mim_id":"602144","title":"BROMODOMAIN, TESTIS-SPECIFIC; BRDT","url":"https://www.omim.org/entry/602144"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Tissue enriched","tissue_distribution":"Detected in some","driving_tissues":[{"tissue":"testis","ntpm":122.8}],"url":"https://www.proteinatlas.org/search/BRDT"},"hgnc":{"alias_symbol":["BRD6","CT9","BRDt"],"prev_symbol":[]},"alphafold":{"accession":"Q58F21","domains":[{"cath_id":"1.20.920.10","chopping":"31-132","consensus_level":"high","plddt":95.6725,"start":31,"end":132},{"cath_id":"1.20.920.10","chopping":"272-375","consensus_level":"high","plddt":96.2812,"start":272,"end":375},{"cath_id":"1.20.1270.220","chopping":"513-542_560-570","consensus_level":"medium","plddt":90.6095,"start":513,"end":570}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q58F21","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q58F21-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q58F21-F1-predicted_aligned_error_v6.png","plddt_mean":62.44},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=BRDT","jax_strain_url":"https://www.jax.org/strain/search?query=BRDT"},"sequence":{"accession":"Q58F21","fasta_url":"https://rest.uniprot.org/uniprotkb/Q58F21.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q58F21/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q58F21"}},"corpus_meta":[{"pmid":"22901802","id":"PMC_22901802","title":"Small-molecule inhibition of BRDT for male contraception.","date":"2012","source":"Cell","url":"https://pubmed.ncbi.nlm.nih.gov/22901802","citation_count":325,"is_preprint":false},{"pmid":"12861021","id":"PMC_12861021","title":"Acetylation-dependent chromatin reorganization by BRDT, a testis-specific bromodomain-containing protein.","date":"2003","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/12861021","citation_count":224,"is_preprint":false},{"pmid":"17728347","id":"PMC_17728347","title":"The first bromodomain of Brdt, a testis-specific member of the BET sub-family of double-bromodomain-containing proteins, is essential for male germ cell differentiation.","date":"2007","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/17728347","citation_count":213,"is_preprint":false},{"pmid":"22922464","id":"PMC_22922464","title":"Bromodomain-dependent stage-specific male genome programming by Brdt.","date":"2012","source":"The EMBO 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fsh.","date":"1997","source":"Genomics","url":"https://pubmed.ncbi.nlm.nih.gov/9367677","citation_count":99,"is_preprint":false},{"pmid":"15261828","id":"PMC_15261828","title":"Identification of unique, differentiation stage-specific patterns of expression of the bromodomain-containing genes Brd2, Brd3, Brd4, and Brdt in the mouse testis.","date":"2004","source":"Gene expression patterns : GEP","url":"https://pubmed.ncbi.nlm.nih.gov/15261828","citation_count":99,"is_preprint":false},{"pmid":"28199965","id":"PMC_28199965","title":"Whole-exome sequencing identified a homozygous BRDT mutation in a patient with acephalic spermatozoa.","date":"2017","source":"Oncotarget","url":"https://pubmed.ncbi.nlm.nih.gov/28199965","citation_count":71,"is_preprint":false},{"pmid":"33637650","id":"PMC_33637650","title":"Discovery and characterization of bromodomain 2-specific inhibitors of BRDT.","date":"2021","source":"Proceedings of the National Academy of Sciences of the United States of 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Bromodomain testis-specific gene (Brdt) characterization and expression in gilthead seabream, Sparus aurata, and European seabass, Dicentrarchus labrax.","date":"2016","source":"European journal of histochemistry : EJH","url":"https://pubmed.ncbi.nlm.nih.gov/27349318","citation_count":9,"is_preprint":false},{"pmid":"24865796","id":"PMC_24865796","title":"BRDT gene sequence in human testicular pathologies and the implication of its single nucleotide polymorphism (rs3088232) on fertility.","date":"2014","source":"Andrology","url":"https://pubmed.ncbi.nlm.nih.gov/24865796","citation_count":8,"is_preprint":false},{"pmid":"22960636","id":"PMC_22960636","title":"Low-hanging fruit: targeting Brdt in the testes.","date":"2012","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/22960636","citation_count":8,"is_preprint":false},{"pmid":"25652540","id":"PMC_25652540","title":"Two bromodomain proteins functionally interact to recapitulate an essential BRDT-like function in 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Sinica","url":"https://pubmed.ncbi.nlm.nih.gov/36239350","citation_count":3,"is_preprint":false},{"pmid":"35279966","id":"PMC_35279966","title":"Epigenetic Dysregulation of BRDT Gene in Testis Tissues of Infertile Men: Case-Control Study.","date":"2022","source":"Cell journal","url":"https://pubmed.ncbi.nlm.nih.gov/35279966","citation_count":2,"is_preprint":false},{"pmid":"22863594","id":"PMC_22863594","title":"[Preparation of anti-BRDT-NY polyclonal antibody and expression of BRDT-NY protein in digestive tract tumors].","date":"2012","source":"Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology","url":"https://pubmed.ncbi.nlm.nih.gov/22863594","citation_count":0,"is_preprint":false},{"pmid":"41984625","id":"PMC_41984625","title":"Structural Basis for BD1-Preferring 2,4-Disubstituted Pyrimidine BRDT Inhibitors.","date":"2026","source":"Journal of medicinal 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indispensable for this remodelling activity.\",\n      \"method\": \"In vitro chromatin remodeling assay on isolated nuclei, bromodomain mutagenesis, ectopic expression in somatic cells with TSA treatment\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution assay with mutagenesis of functional domains, multiple orthogonal methods in one study\",\n      \"pmids\": [\"12861021\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"The first bromodomain (BD1) of Brdt is essential for male germ cell differentiation in vivo; mice lacking only BD1 are sterile with aberrant spermatid morphogenesis and lack peri-nuclear heterochromatin foci. Brdt protein (but not BrdtΔBD1) associates with the promoter of histone H1t, and BD1 deletion leads to 3-fold increased H1t levels.\",\n      \"method\": \"Targeted mutagenesis (deletion of BD1 in mice), chromatin immunoprecipitation (ChIP), quantitative RT-PCR, immunostaining\",\n      \"journal\": \"Development (Cambridge, England)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean genetic KO with defined phenotype, ChIP confirming promoter occupancy, replicated across multiple methods\",\n      \"pmids\": [\"17728347\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"JQ1, a small-molecule inhibitor, occupies the BRDT acetyl-lysine binding pocket and prevents recognition of acetylated histone H4, as confirmed by crystallography. In mice, JQ1 reduces seminiferous tubule area, testis size, and spermatozoa number and motility, causing a complete and reversible contraceptive effect at the spermatocyte and round spermatid stages.\",\n      \"method\": \"Biochemical binding assay, X-ray crystallography of JQ1-BRDT complex, in vivo mouse treatment\",\n      \"journal\": \"Cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure plus in vivo functional validation, replicated across biochemical and animal models\",\n      \"pmids\": [\"22901802\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Brdt acts as a master regulator of meiotic and post-meiotic gene expression programs; its first bromodomain directs genome-wide replacement of histones by transition proteins during global chromatin hyperacetylation at post-meiotic stages, while other domains drive a spermatogenic transcriptional program at meiotic stages.\",\n      \"method\": \"Genetic mouse models (Brdt knockout and BD1 deletion), genome-wide transcriptional analysis, ChIP, immunostaining\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean genetic models with defined stage-specific phenotypes, genome-wide chromatin and transcriptional analyses\",\n      \"pmids\": [\"22922464\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Brdt colocalizes with acetylated H4 in elongating spermatids and induces acetylation-dependent but ATP-independent chromatin reorganization in round spermatids. Brdt interacts with Smarce1 (a SWI/SNF family member) via its N-terminus, and this interaction increases upon histone hyperacetylation both in vitro and in vivo.\",\n      \"method\": \"Immunocytochemistry, in vitro chromatin remodeling assay, co-immunoprecipitation, pulldown assay\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP and in vitro remodeling assay in single lab, two orthogonal methods\",\n      \"pmids\": [\"22215678\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"BRDT forms a complex with multiple spliceosome components (Srsf2, Ddx5, Hnrnpk, Tardbp) and is required for mRNA splicing and 3'-UTR truncation in round spermatids. Loss of BD1 leads to longer 3'-UTRs and reduced protein levels of splicing factors, and BD1 is essential for these functions.\",\n      \"method\": \"Transcriptome analysis of Brdt(ΔBD1/ΔBD1) vs control round spermatids, co-immunoprecipitation of BRDT with spliceosome components, RNA-seq\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP with multiple spliceosome components plus transcriptome-level functional validation in genetic model\",\n      \"pmids\": [\"22570411\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"BRDT forms complexes with HDAC1, PRMT5, and TRIM28 in round spermatids, as shown by affinity purification of FLAG-tagged BRDT and co-IP from testicular extracts. These complexes bind the H1t promoter, and this binding is lost in Brdt(ΔBD1) mutants, correlating with elevated H1t expression, indicating a role for BRDT-containing complexes in transcriptional repression.\",\n      \"method\": \"Affinity purification of FLAG-tagged BRDT, co-immunoprecipitation from testicular extracts, ChIP, immunofluorescence\",\n      \"journal\": \"Journal of cellular biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP from testicular extracts plus ChIP validation, single lab\",\n      \"pmids\": [\"26565999\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"BRDT interacts with nucleosomes through its first bromodomain (BD1) but not second bromodomain (BD2); acetylated histone recognition by BD1 is complemented by a bromodomain-DNA interaction, which together enhance BRDT's nucleosome binding affinity, specificity, and localization to acetylated chromatin in cells. Conservation of DNA binding in BRD2, BRD3, and BRD4 bromodomains suggests this is a shared BET mechanism.\",\n      \"method\": \"NMR, biochemical nucleosome binding assay with site-specifically acetylated nucleosomes, cell-based chromatin localization assay\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — NMR structural characterization plus biochemical reconstitution with site-specifically acetylated nucleosomes and cell-based validation\",\n      \"pmids\": [\"27991587\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Complete loss of BRDT disrupts meiotic sex chromosome inactivation in spermatocytes, affects synapsis and silencing of the X and Y chromosomes, disrupts global chromatin organization and histone modifications at the synaptonemal complex, and alters the homeostasis of crossover formation and localization during pachynema, establishing BRDT as an essential regulator of meiotic chromatin organization.\",\n      \"method\": \"Complete Brdt knockout mouse model, immunofluorescence, ChIP, FISH, analysis of meiotic progression\",\n      \"journal\": \"PLoS genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean genetic KO with multiple defined meiotic phenotypes assessed by orthogonal methods\",\n      \"pmids\": [\"29513658\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"PHF7 acts as an E3 ubiquitin ligase for histone H3K14 in post-meiotic spermatids, and its ubiquitin ligase activity stabilizes BRDT by attenuating ubiquitination of BRDT itself, thereby enabling histone-to-protamine exchange. Loss of PHF7 E3 ligase activity leads to dysregulation of BRDT in early condensing spermatids and defects in histone-to-protamine exchange.\",\n      \"method\": \"Phf7-deficient mice, Phf7 C160A knockin mice (impaired E3 ligase), biochemical ubiquitination assay, co-immunoprecipitation\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic knockin of catalytic mutant plus biochemical ubiquitination assay and rescue experiments, multiple orthogonal methods\",\n      \"pmids\": [\"32726616\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"The first bromodomain of Brdt is required for chromocenter integrity in spermatids; Brdt(ΔBD1/ΔBD1) mutants exhibit fragmented chromocenters with increased HP1α levels and ectopic H1fnt localization. Brdt protein is normally excluded from the chromocenter and appears to separate Sirt1 from contact with the chromocenter, a spatial relationship lost upon BD1 deletion.\",\n      \"method\": \"Brdt(ΔBD1/ΔBD1) mouse model, immunofluorescence microscopy, co-localization analysis\",\n      \"journal\": \"Developmental biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean genetic model with defined structural phenotype, immunofluorescence localization data, single lab\",\n      \"pmids\": [\"22020252\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"In esophageal squamous cell carcinoma (ESCC), BRDT colocalizes and interacts with ΔNp63 at super-enhancers to drive transcriptional activation of ΔNp63 target genes (including KRT14, FAT2, PTHLH) that are involved in squamous cell identity; BRDT promotes cell migration but is dispensable for proliferation in this context. BET PROTAC MZ1 preferentially degrades BRDT over BRD2, BRD3, and BRD4.\",\n      \"method\": \"ChIP-seq, genome-wide chromatin interaction studies, transcriptome analysis, co-immunoprecipitation, CRISPR/shRNA knockdown\",\n      \"journal\": \"Cell death and differentiation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple genome-wide and biochemical methods in single lab, co-localization and interaction confirmed\",\n      \"pmids\": [\"33658703\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"CDD-1102 is a selective BRDT-BD2 inhibitor with low nanomolar potency and >1,000-fold selectivity over BRDT-BD1. Co-crystal structures of BRDT-BD2 with CDD-1102 and CDD-1302 (at 2.27 and 1.90 Å resolution) reveal BRDT-BD2-specific contacts explaining their affinity and selectivity.\",\n      \"method\": \"DNA-encoded chemical library screening, AlphaScreen competition assay, X-ray crystallography of BRDT-BD2 inhibitor complexes, BROMOscan profiling\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structures at high resolution plus biochemical selectivity profiling using orthogonal methods\",\n      \"pmids\": [\"33637650\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"In renal cell carcinoma cells, BRDT interacts with eIF4EBP1 (identified by immunoprecipitation and mass spectrometry), and BRDT inhibition or knockdown suppresses eIF4EBP1 protein expression and c-myc transcription; BRDT regulates c-myc promoter activity, and eIF4EBP1 overexpression partially rescues the growth inhibition caused by BRDT inhibition.\",\n      \"method\": \"Co-immunoprecipitation, mass spectrometry, siRNA knockdown, luciferase reporter assay, in vivo xenograft\",\n      \"journal\": \"Oncology reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP/MS identification plus functional rescue experiments, single lab\",\n      \"pmids\": [\"33125143\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"A homozygous BRDT mutation (p.G928D) in the P-TEFb binding domain causes acephalic spermatozoa and mis-regulation of 899 genes compared to wild-type BRDT-expressing cells, with upregulated genes enriched in intracellular transport, RNA splicing, cell cycle, and DNA metabolic processes.\",\n      \"method\": \"Whole-exome sequencing, RNA-sequencing of mutant vs wild-type cells, Gene Ontology analysis\",\n      \"journal\": \"Oncotarget\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — patient mutation identification with transcriptome analysis, no direct biochemical confirmation of P-TEFb interaction disruption\",\n      \"pmids\": [\"28199965\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"During meiotic prophase I, RNA Pol II is loaded and maintained in a paused state early during prophase I; in later stages, paused Pol II is released in a coordinated transcriptional burst mediated by both A-MYB and BRDT, resulting in approximately 3-fold increase in transcription at genes required for meiotic progression.\",\n      \"method\": \"Genome-wide chromatin accessibility (ATAC-seq), nascent transcription measurement (GRO-seq), processed mRNA profiling in staged spermatocytes\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple genome-wide assays establishing Pol II pause-release coordination with BRDT, single lab\",\n      \"pmids\": [\"36990976\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Bivalent BET inhibitors show increased potency and selectivity for BRDT over BRD4; X-ray crystallography and solution studies reveal that bivalent inhibitors induce unique dimeric structural states of BRDT that differ from those of BRD4, explaining the differential selectivity through protein conformational plasticity.\",\n      \"method\": \"X-ray crystallography, biophysical solution studies, cell-based activity assays, structure-activity relationship analysis\",\n      \"journal\": \"Journal of medicinal chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — crystal structures with functional validation showing unique BRDT conformational states, multiple orthogonal structural and biophysical methods\",\n      \"pmids\": [\"35867655\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"BRDT is a testis-specific BET family double-bromodomain protein that functions as a master epigenetic regulator of spermatogenesis: its first bromodomain (BD1) directly recognizes acetylated histone H4 and, complemented by a bromodomain-DNA interaction, directs genome-wide histone replacement by transition proteins in post-meiotic spermatids; it also drives stage-specific transcriptional programs (including Pol II pause release in meiosis in concert with A-MYB), represses genes via complexes with HDAC1/PRMT5/TRIM28, regulates mRNA splicing and 3'-UTR processing through interactions with spliceosome components, controls meiotic sex chromosome inactivation and crossover formation, and is itself stabilized by PHF7-mediated ubiquitination of histone H3K14 which attenuates BRDT ubiquitination—all of which are essential for male fertility.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"BRDT is a testis-specific BET-family double-bromodomain protein that serves as a master epigenetic regulator of meiotic and post-meiotic gene expression and chromatin remodeling during spermatogenesis [#3]. Its first bromodomain (BD1) recognizes hyperacetylated histone H4 in an acetylation-dependent manner and drives large-scale, ATP-independent chromatin reorganization [#0]; BD1-mediated acetyl-lysine recognition is complemented by a direct bromodomain–DNA contact that enhances nucleosome binding affinity, specificity, and localization to acetylated chromatin [#7]. Through BD1 this activity directs the genome-wide replacement of histones by transition proteins during the global hyperacetylation of post-meiotic spermatids [#3], and BD1 is required in vivo for spermatid morphogenesis, peri-nuclear heterochromatin foci, and chromocenter integrity [#1, #10]. BRDT also assembles into repressive complexes with HDAC1, PRMT5, and TRIM28 that occupy the H1t promoter, with BD1 loss derepressing H1t [#6, #1], and it partners with spliceosome components (Srsf2, Ddx5, Hnrnpk, Tardbp) to control mRNA splicing and 3'-UTR truncation in round spermatids [#5]. In meiosis BRDT cooperates with A-MYB to release paused RNA Pol II in a coordinated transcriptional burst at meiotic genes [#15] and is required for meiotic sex chromosome inactivation, synapsis, and crossover homeostasis [#8]. BRDT protein stability is controlled by PHF7, an E3 ligase for histone H3K14 that attenuates BRDT ubiquitination to enable histone-to-protamine exchange [#9]. The acetyl-lysine pocket is druggable: JQ1 occupies it and produces a reversible contraceptive effect in mice [#2], establishing BRDT as a male contraceptive target. Beyond spermatogenesis, BRDT has been implicated in cancer contexts including ΔNp63-driven super-enhancer transcription in esophageal squamous cell carcinoma and c-myc/eIF4EBP1 regulation in renal cell carcinoma [#11, #13].\",\n  \"teleology\": [\n    {\n      \"year\": 2003,\n      \"claim\": \"Established the core biochemical activity of BRDT—recognition of hyperacetylated H4 and induction of chromatin compaction—answering whether BRDT reads acetyl marks and reorganizes chromatin.\",\n      \"evidence\": \"In vitro chromatin remodeling on isolated nuclei with bromodomain mutagenesis and ectopic expression in TSA-treated somatic cells\",\n      \"pmids\": [\"12861021\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not establish the in vivo germ-cell substrate or downstream effectors\", \"ATP-independent mechanism of compaction not resolved structurally\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Demonstrated that BD1 is genetically essential for spermatid differentiation in vivo and that BRDT occupies a specific target promoter (H1t), linking the biochemical reader function to fertility.\",\n      \"evidence\": \"BD1-deletion mouse, ChIP, qRT-PCR, immunostaining\",\n      \"pmids\": [\"17728347\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not define the full repertoire of BRDT-bound promoters\", \"Mechanism of H1t repression not yet defined\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Resolved BD1's structural role in spermatid nuclear architecture, showing BD1 is required for chromocenter integrity and spatial exclusion of HP1α and Sirt1.\",\n      \"evidence\": \"BD1-deletion mouse with immunofluorescence and colocalization analysis\",\n      \"pmids\": [\"22020252\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single lab, descriptive localization\", \"Causal link between chromocenter defect and infertility not dissected\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Partitioned BRDT function across spermatogenic stages, establishing it as a master regulator that uses BD1 for post-meiotic histone replacement and other domains for meiotic transcription, and identified its physical partners.\",\n      \"evidence\": \"Brdt knockout and BD1-deletion mice with genome-wide transcriptional/ChIP analysis; co-IP with Smarce1 and with spliceosome components (Srsf2, Ddx5, Hnrnpk, Tardbp); JQ1 crystal structure with in vivo contraception\",\n      \"pmids\": [\"22922464\", \"22215678\", \"22570411\", \"22901802\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism by which BD1 directs transition-protein exchange not biochemically reconstituted\", \"Splicing/3'-UTR control mechanism not resolved at single-gene level\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Defined BRDT's repressive complex composition, showing it assembles with HDAC1, PRMT5, and TRIM28 at the H1t promoter to enforce gene silencing.\",\n      \"evidence\": \"FLAG-BRDT affinity purification, co-IP from testicular extracts, ChIP, immunofluorescence\",\n      \"pmids\": [\"26565999\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Stoichiometry and assembly order of the complex unknown\", \"Single lab; complex not structurally characterized\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Explained how BRDT achieves chromatin specificity, showing BD1 recognition of acetyl-lysine is complemented by a bromodomain–DNA interaction that enhances nucleosome binding.\",\n      \"evidence\": \"NMR, biochemical binding with site-specifically acetylated nucleosomes, cell-based localization\",\n      \"pmids\": [\"27991587\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"DNA-binding contribution to in vivo histone replacement not genetically tested\", \"BD2 functional role left undefined\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Extended BRDT function to meiotic chromosome biology, establishing it as essential for meiotic sex chromosome inactivation, synapsis, and crossover homeostasis.\",\n      \"evidence\": \"Complete Brdt knockout mouse, immunofluorescence, ChIP, FISH, meiotic progression analysis\",\n      \"pmids\": [\"29513658\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular targets mediating MSCI and crossover control not identified\", \"Direct chromatin mechanism at the synaptonemal complex unresolved\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Identified an upstream regulator of BRDT stability, showing PHF7-mediated H3K14 ubiquitination attenuates BRDT ubiquitination to permit histone-to-protamine exchange.\",\n      \"evidence\": \"Phf7-null and Phf7 C160A catalytic-mutant knockin mice, in vitro ubiquitination assay, co-IP\",\n      \"pmids\": [\"32726616\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"The E3 ligase ubiquitinating BRDT not identified\", \"How H3K14ub mechanistically shields BRDT from degradation unknown\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Placed BRDT in the meiotic transcriptional-burst pathway, showing it acts with A-MYB to release paused Pol II at meiotic genes.\",\n      \"evidence\": \"ATAC-seq, GRO-seq, and processed-mRNA profiling in staged spermatocytes\",\n      \"pmids\": [\"36990976\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct biochemical coupling of BRDT to P-TEFb/pause-release machinery not shown\", \"Single lab\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Showed BRDT can be co-opted in cancer, acting at ΔNp63 super-enhancers in ESCC and regulating c-myc/eIF4EBP1 in renal cell carcinoma, while advancing selective chemical tools.\",\n      \"evidence\": \"ChIP-seq, chromatin interaction studies, co-IP/MS, knockdown and rescue in tumor cells; selective BRDT-BD2 inhibitor co-crystal structures\",\n      \"pmids\": [\"33658703\", \"33125143\", \"33637650\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Physiological relevance of somatic BRDT expression unclear\", \"Direct vs indirect c-myc regulation not fully separated\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Demonstrated BRDT conformational plasticity exploitable for selectivity, with bivalent inhibitors inducing unique dimeric states distinct from BRD4.\",\n      \"evidence\": \"X-ray crystallography, solution biophysics, cell-based assays, SAR\",\n      \"pmids\": [\"35867655\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional consequence of induced BRDT dimerization in cells unknown\", \"Relevance to native BRDT oligomeric state not established\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How BRDT mechanistically converts acetyl-histone recognition into directed transition-protein/protamine exchange, and how its meiotic and post-meiotic roles are temporally switched, remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No reconstituted system couples BD1 reading to histone-to-protamine exchange\", \"Domain-level switch between meiotic transcription and post-meiotic remodeling undefined\", \"Direct enzymatic partners executing chromatin reorganization unidentified\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0042393\", \"supporting_discovery_ids\": [0, 1, 2, 7]},\n      {\"term_id\": \"GO:0003677\", \"supporting_discovery_ids\": [7]},\n      {\"term_id\": \"GO:0140110\", \"supporting_discovery_ids\": [3, 6, 11, 15]},\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [0, 4]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0000228\", \"supporting_discovery_ids\": [1, 8, 10]},\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0, 4]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-4839726\", \"supporting_discovery_ids\": [0, 3, 7]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [3, 6, 15]},\n      {\"term_id\": \"R-HSA-1474165\", \"supporting_discovery_ids\": [1, 3, 8]},\n      {\"term_id\": \"R-HSA-8953854\", \"supporting_discovery_ids\": [5]}\n    ],\n    \"complexes\": [\"BRDT-HDAC1-PRMT5-TRIM28 repressive complex\", \"BRDT-spliceosome complex\"],\n    \"partners\": [\"SMARCE1\", \"HDAC1\", \"PRMT5\", \"TRIM28\", \"SRSF2\", \"DDX5\", \"HNRNPK\", \"PHF7\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":8,"faith_total":8,"faith_pct":100.0}}