{"gene":"HSD3B2","run_date":"2026-04-28T18:06:53","timeline":{"discoveries":[{"year":1999,"finding":"HSD3B2 encodes a bifunctional 3β-hydroxysteroid dehydrogenase/Δ5-Δ4-isomerase that converts Δ5-steroids to Δ4-steroids (e.g., DHEA to androstenedione, pregnenolone to progesterone); 25 disease-causing missense mutations were functionally characterized by transient expression in 293 cells with [14C]-DHEA as substrate, revealing that salt-wasting forms result from complete loss of activity while non-salt-losing forms retain partial activity; protein instability was identified as a novel molecular mechanism underlying some mutations.","method":"Site-directed mutagenesis, transient expression in 293 cells, in vitro enzyme activity assay with radiolabeled substrate, Northern/Western blot, in vitro transcription/translation in rabbit reticulocyte lysates","journal":"The Journal of clinical endocrinology and metabolism","confidence":"High","confidence_rationale":"Tier 1 — large-scale in vitro mutagenesis and functional reconstitution with multiple orthogonal methods across 25 mutants","pmids":["10599696"],"is_preprint":false},{"year":2000,"finding":"The A10E missense mutation in HSD3B2 (located in the putative NAD-binding domain) abolishes all detectable enzyme activity when expressed in Ad293 cells, demonstrating that Ala10 in the NAD-binding domain is essential for catalytic function.","method":"Site-directed mutagenesis, transient expression in Ad293 cells, in vitro enzyme activity assay","journal":"The Journal of clinical endocrinology and metabolism","confidence":"High","confidence_rationale":"Tier 1 — direct in vitro functional assay with mutagenesis establishing active-site requirement","pmids":["10843183"],"is_preprint":false},{"year":2004,"finding":"The transcription factor YY1 binds two distinct sites within HSD3B2 intron 1; binding to the second YY1 site (35 bp downstream of the 3β1-A element) is required for maximal basal HSD3B2 promoter activity, as mutation of this site reduces transcription by ~50%, and complete abrogation of both YY1 sites reduces activity to the level of a construct lacking all of intron 1.","method":"Reporter gene (transient transfection) assay, gel shift assay, mutational analysis, competition analysis, anti-YY1 antibody supershift, Western blot","journal":"Journal of molecular endocrinology","confidence":"High","confidence_rationale":"Tier 1–2 — multiple orthogonal methods (gel shift, supershift, mutagenesis, reporter assays) in a single study identifying YY1 as the transcriptional activator","pmids":["15291746"],"is_preprint":false},{"year":2010,"finding":"HSD3B2 and cytochrome b5 (CYB5A) are co-expressed in a subset of human adrenal cortical cells at the zona fasciculata/zona reticularis border; both are required for androstenedione production, as shown by trilostane (HSD3B2 inhibitor) blocking androstenedione output and siRNA knockdown of CYB5A significantly reducing androstenedione in H295R cells.","method":"Immunohistochemistry co-localization in human adrenal tissue, pharmacological inhibition with trilostane, siRNA knockdown, cell culture steroid measurement","journal":"The Journal of steroid biochemistry and molecular biology","confidence":"High","confidence_rationale":"Tier 2 — direct localization with functional consequence confirmed by two independent loss-of-function approaches (inhibitor + siRNA)","pmids":["21185375"],"is_preprint":false},{"year":2012,"finding":"Metformin inhibits HSD3B2 enzymatic activity (and reduces its expression) in NCI-H295R steroidogenic cells via inhibition of mitochondrial respiratory chain complex I, independently of AMPK signaling; direct complex I inhibition by rotenone similarly inhibits HSD3B2 activity, placing complex I upstream of HSD3B2 activity regulation.","method":"In vitro cell-based steroidogenesis assay (NCI-H295R), pharmacological inhibition (metformin, rotenone), Western blot, mRNA quantification, mitochondrial complex I activity assay","journal":"Endocrinology","confidence":"High","confidence_rationale":"Tier 2 — epistasis established by two independent inhibitors; multiple orthogonal methods including direct complex I activity measurement","pmids":["22778212"],"is_preprint":false},{"year":2015,"finding":"Decanoic acid (DA) inhibits HSD3B2 transcription and protein expression in NCI-H295R cells by reducing cAMP-stimulated recruitment of the orphan nuclear receptor Nur77 to the HSD3B2 promoter, thereby decreasing androgen biosynthesis; this mechanism requires cAMP pathway activation.","method":"Cell-based steroidogenesis assay, chromatin immunoprecipitation (Nur77 recruitment to HSD3B2 promoter), RT-PCR, Western blot, in vivo rat PCOS model validation","journal":"Endocrinology","confidence":"High","confidence_rationale":"Tier 2 — ChIP identifying specific transcription factor recruitment to HSD3B2 promoter, validated in vitro and in vivo","pmids":["26465200"],"is_preprint":false},{"year":2019,"finding":"GATA-binding factor 1 (GATA1) is a transcriptional activator of the HSD3B2 promoter in steroidogenic cells; baicalin inhibits HSD3B2 expression and androgen production by reducing GATA1 recruitment to the HSD3B2 promoter, as established by dual luciferase reporter assay, RNA interference of GATA1, and promoter mutation studies.","method":"Gene expression profiling, dual luciferase reporter assay, RNA interference, site-directed mutagenesis of HSD3B2 promoter, ELISA for testosterone, in vivo PCOS rat model","journal":"The Journal of endocrinology","confidence":"High","confidence_rationale":"Tier 1–2 — multiple orthogonal approaches (reporter assay, RNAi, mutagenesis) identifying GATA1 as direct HSD3B2 promoter transactivator","pmids":["30650063"],"is_preprint":false},{"year":2014,"finding":"Two novel HSD3B2 missense mutations (p.Y190C and p.S218P), located adjacent to the predicted substrate-binding pocket in 3D homology modeling, severely impair enzyme activity in vitro but retain higher residual activity toward 17-OH pregnenolone than toward other Δ5-steroids, suggesting these residues influence substrate-binding affinity differentially for distinct substrates.","method":"Site-directed mutagenesis, in vitro enzyme activity assay in transfected cells, 3D homology modeling","journal":"Clinical endocrinology","confidence":"Medium","confidence_rationale":"Tier 1 — in vitro functional assay with mutagenesis, but single lab and novel substrate-selectivity observation not independently replicated","pmids":["24372086"],"is_preprint":false},{"year":2015,"finding":"The p.G250V HSD3B2 mutation reduces Vmax for progesterone synthesis (to ~20–27% of wild-type) without altering Km for pregnenolone and without affecting protein expression or intracellular localization; homology modeling places G250 in the L239-Q251 loop adjacent to a β-sheet in the NAD+-binding domain, suggesting this loop is important for catalytic activity.","method":"In vitro enzyme activity assay in COS-7 cells (Vmax/Km kinetics), Western blot, immunofluorescence, molecular homology modeling","journal":"The Journal of clinical endocrinology and metabolism","confidence":"Medium","confidence_rationale":"Tier 1 — kinetic characterization with mutagenesis plus structural modeling; single-lab study","pmids":["25322271"],"is_preprint":false},{"year":2011,"finding":"Sunitinib inhibits HSD3B2 in adrenocortical cells by down-regulating HSD3B2 mRNA and protein (not by direct enzymatic inhibition), as demonstrated by steroid profiling showing accumulation of HSD3B2 substrates, absence of direct inhibition in yeast microsomes expressing HSD3B2, and dose-dependent reduction of HSD3B2 mRNA/protein in NCI-H295R cells.","method":"Gas chromatography-mass spectrometry steroid profiling, yeast microsome HSD3B2 direct inhibition assay, RT-PCR, Western blot in ACC cell lines","journal":"Frontiers in endocrinology","confidence":"Medium","confidence_rationale":"Tier 2 — multiple orthogonal methods distinguishing indirect (transcriptional) from direct enzymatic inhibition","pmids":["22654799"],"is_preprint":false},{"year":2016,"finding":"DNA methylation is not the mechanism responsible for zone-specific down-regulation of HSD3B2 in the human adrenal zona reticularis, as HSD3B2 lacks CpG islands, and bisulfite/methylation analysis did not reveal adrenal zone-specific differences.","method":"RT-qPCR on microdissected adrenal zones, methylation analysis, CpG island analysis","journal":"Molecular and cellular endocrinology","confidence":"Medium","confidence_rationale":"Tier 2 — direct epigenetic analysis with microdissected tissue; single lab, mechanistically informative negative result","pmids":["27670690"],"is_preprint":false}],"current_model":"HSD3B2 encodes a bifunctional NAD+-dependent microsomal enzyme (3β-hydroxysteroid dehydrogenase/Δ5-Δ4-isomerase) that catalyzes conversion of Δ5-steroids to Δ4-steroids in adrenals and gonads; its catalytic activity depends on an intact NAD+-binding domain (including Ala10 and the L239-Q251 loop), and its expression is transcriptionally activated by YY1 (via intron 1 elements) and GATA1 (via the proximal promoter), while being suppressed by inhibition of mitochondrial complex I (as occurs with metformin), reduced Nur77 recruitment (by decanoic acid), or reduced GATA1 recruitment (by baicalin); co-expression with CYB5A in zona fasciculata/reticularis border cells is required for adrenal androstenedione production."},"narrative":{"teleology":[{"year":1999,"claim":"Systematic functional characterization of 25 disease-causing HSD3B2 missense mutations established that the degree of residual enzyme activity directly determines clinical severity (salt-wasting vs. non-salt-losing congenital adrenal hyperplasia) and identified protein instability as a novel pathogenic mechanism, transforming genotype–phenotype understanding.","evidence":"Site-directed mutagenesis with transient expression in 293 cells using [¹⁴C]-DHEA substrate conversion, Northern/Western blot, and in vitro translation","pmids":["10599696"],"confidence":"High","gaps":["Structural basis for instability of specific mutant proteins not determined","Residual activity measured in heterologous cells may not reflect in vivo adrenal/gonadal context"]},{"year":2000,"claim":"Demonstration that the A10E mutation in the NAD⁺-binding domain abolishes all catalytic activity established Ala10 as essential for cofactor binding and enzyme function, pinpointing the cofactor-binding domain as a critical determinant of HSD3B2 activity.","evidence":"Site-directed mutagenesis and enzyme activity assay in transfected Ad293 cells","pmids":["10843183"],"confidence":"High","gaps":["No crystal structure or direct cofactor-binding measurement to confirm NAD⁺ interaction at Ala10","Other residues in the NAD⁺-binding domain not systematically tested"]},{"year":2004,"claim":"Identification of YY1 as a transcription factor binding two sites in intron 1 and required for maximal basal HSD3B2 promoter activity provided the first defined cis-regulatory mechanism for HSD3B2 expression.","evidence":"Gel shift, antibody supershift, mutagenesis of YY1 sites, and reporter gene assays","pmids":["15291746"],"confidence":"High","gaps":["Cell type-specific relevance of YY1 in adrenal vs. gonadal tissues not tested","Chromatin-level confirmation (e.g., ChIP) was not performed"]},{"year":2010,"claim":"Co-localization of HSD3B2 and CYB5A at the zona fasciculata/reticularis border, combined with loss-of-function experiments, established that androstenedione production in the adrenal requires cooperative activity of both enzymes, explaining zonal heterogeneity in adrenal androgen output.","evidence":"Immunohistochemistry on human adrenal tissue, trilostane inhibition, and siRNA knockdown of CYB5A in H295R cells","pmids":["21185375"],"confidence":"High","gaps":["Whether HSD3B2 and CYB5A physically interact or function independently at the same membrane is unknown","Mechanism establishing their co-expression in border-zone cells not identified"]},{"year":2012,"claim":"Metformin and rotenone both inhibit HSD3B2 expression and activity via mitochondrial complex I inhibition (independently of AMPK), revealing an unexpected link between mitochondrial electron transport and steroidogenic gene regulation.","evidence":"Pharmacological inhibition with metformin and rotenone in NCI-H295R cells, complex I activity assay, Western blot, mRNA quantification","pmids":["22778212"],"confidence":"High","gaps":["Signaling intermediates between complex I and HSD3B2 transcription/activity not identified","Relevance to in vivo adrenal steroidogenesis during metformin therapy not confirmed in human tissue"]},{"year":2014,"claim":"Novel mutations (Y190C, S218P) near the modeled substrate-binding pocket showed substrate-selective impairment, retaining higher residual activity for 17-OH pregnenolone than other Δ5-steroids, revealing that distinct residues contribute differentially to binding of individual substrates.","evidence":"Site-directed mutagenesis, enzyme activity assay in transfected cells, 3D homology modeling","pmids":["24372086"],"confidence":"Medium","gaps":["Substrate selectivity based on homology model without experimental structural validation","Observation from a single lab, not independently replicated","Kinetic parameters (Km, Vmax) for each substrate not fully determined"]},{"year":2015,"claim":"Kinetic characterization of the G250V mutation showed reduced Vmax without altered Km or mislocalization, identifying the L239–Q251 loop as important for catalytic turnover rather than substrate recognition, and decanoic acid was shown to suppress HSD3B2 transcription by blocking Nur77 recruitment to the promoter, adding Nur77 to the roster of direct HSD3B2 transcriptional regulators.","evidence":"Enzyme kinetics in COS-7 cells with homology modeling (G250V); ChIP for Nur77 at HSD3B2 promoter, RT-PCR, Western blot in H295R cells with in vivo PCOS rat validation (decanoic acid)","pmids":["25322271","26465200"],"confidence":"High","gaps":["No crystal structure to confirm loop conformation or catalytic mechanism","Nur77 ChIP performed only in H295R cells; relevance across steroidogenic tissues unknown"]},{"year":2016,"claim":"Ruling out DNA methylation as the mechanism for zona reticularis-specific HSD3B2 down-regulation narrowed the search for the epigenetic or trans-acting factor responsible for adrenal zonal expression patterning.","evidence":"Bisulfite sequencing and methylation analysis on microdissected human adrenal zones","pmids":["27670690"],"confidence":"Medium","gaps":["Alternative epigenetic marks (histone modifications, chromatin accessibility) not examined","Single-lab study on limited number of adrenal specimens","The actual mechanism of zone-specific silencing remains unidentified"]},{"year":2019,"claim":"Identification of GATA1 as a direct transcriptional activator of HSD3B2 — binding the proximal promoter and being required for basal expression — completed a picture of three distinct positive regulators (YY1, Nur77, GATA1) acting at different promoter/intronic elements.","evidence":"Dual luciferase reporter assay, GATA1 RNAi, HSD3B2 promoter site-directed mutagenesis, in vivo PCOS rat model","pmids":["30650063"],"confidence":"High","gaps":["Combinatorial or hierarchical relationships among YY1, Nur77, and GATA1 at the HSD3B2 locus not established","GATA1 role validated primarily in H295R cells; relevance to gonadal HSD3B2 expression unknown"]},{"year":null,"claim":"An experimentally determined three-dimensional structure for HSD3B2 is lacking, and the mechanism by which mitochondrial complex I status is transduced to HSD3B2 transcriptional regulation remains unknown; additionally, the cis-regulatory logic governing adrenal zone-specific silencing has not been identified.","evidence":"","pmids":[],"confidence":"High","gaps":["No crystal or cryo-EM structure available","Signaling pathway from complex I to HSD3B2 transcription undefined","Mechanism of zona reticularis-specific HSD3B2 silencing unresolved","Combinatorial regulation by YY1, Nur77, and GATA1 not integrated"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016491","term_label":"oxidoreductase activity","supporting_discovery_ids":[0,1,7,8]},{"term_id":"GO:0016853","term_label":"isomerase activity","supporting_discovery_ids":[0,7]}],"localization":[{"term_id":"GO:0005783","term_label":"endoplasmic reticulum","supporting_discovery_ids":[3,8]}],"pathway":[{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[0,1,3,7,8]}],"complexes":[],"partners":["CYB5A","YY1","GATA1","NR4A1"],"other_free_text":[]},"mechanistic_narrative":"HSD3B2 encodes a bifunctional NAD⁺-dependent microsomal 3β-hydroxysteroid dehydrogenase/Δ5→Δ4-isomerase that catalyzes the obligatory conversion of Δ5-steroids (pregnenolone, DHEA, 17-OH pregnenolone) to their Δ4-products (progesterone, androstenedione, 17-OH progesterone), a rate-limiting step in adrenal and gonadal steroidogenesis [PMID:10599696]. Catalytic competence requires an intact NAD⁺-binding domain — Ala10 is essential for all detectable activity, and the L239–Q251 loop modulates Vmax without affecting substrate affinity — while mutations near the substrate-binding pocket differentially impair conversion of individual Δ5-substrates [PMID:10843183, PMID:25322271, PMID:24372086]. Transcription of HSD3B2 is positively regulated by YY1 (via intron 1 elements), GATA1 (via the proximal promoter), and Nur77 (recruited upon cAMP stimulation), while mitochondrial complex I inhibition by metformin or rotenone suppresses both expression and activity independently of AMPK [PMID:15291746, PMID:30650063, PMID:26465200, PMID:22778212]. Loss-of-function mutations cause 3β-hydroxysteroid dehydrogenase deficiency, a form of congenital adrenal hyperplasia in which complete activity loss produces salt-wasting disease and partial activity loss produces a non-salt-losing phenotype [PMID:10599696]."},"prefetch_data":{"uniprot":{"accession":"P26439","full_name":"3 beta-hydroxysteroid dehydrogenase/Delta 5-->4-isomerase type 2","aliases":["3 beta-hydroxysteroid dehydrogenase/Delta 5-->4-isomerase type II","3-beta-HSD II","3-beta-HSD adrenal and gonadal type"],"length_aa":372,"mass_kda":42.1,"function":"3-beta-HSD is a bifunctional enzyme, that catalyzes the oxidative conversion of Delta(5)-ene-3-beta-hydroxy steroid, and the oxidative conversion of ketosteroids. The 3-beta-HSD enzymatic system plays a crucial role in the biosynthesis of all classes of hormonal steroids","subcellular_location":"Endoplasmic reticulum membrane; Mitochondrion membrane","url":"https://www.uniprot.org/uniprotkb/P26439/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/HSD3B2","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/HSD3B2","total_profiled":1310},"omim":[{"mim_id":"613890","title":"3-@BETA-HYDROXYSTEROID DEHYDROGENASE 2; HSD3B2","url":"https://www.omim.org/entry/613890"},{"mim_id":"604453","title":"NUCLEAR RECEPTOR SUBFAMILY 5, GROUP A, MEMBER 2; NR5A2","url":"https://www.omim.org/entry/604453"},{"mim_id":"201810","title":"ADRENAL HYPERPLASIA, CONGENITAL, DUE TO 3-BETA-HYDROXYSTEROID DEHYDROGENASE 2 DEFICIENCY","url":"https://www.omim.org/entry/201810"},{"mim_id":"139139","title":"NUCLEAR RECEPTOR SUBFAMILY 4, GROUP A, MEMBER 1; NR4A1","url":"https://www.omim.org/entry/139139"},{"mim_id":"109715","title":"3-@BETA-HYDROXYSTEROID DEHYDROGENASE 1; HSD3B1","url":"https://www.omim.org/entry/109715"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Endoplasmic reticulum","reliability":"Approved"},{"location":"Primary cilium","reliability":"Approved"},{"location":"Nucleoli","reliability":"Additional"},{"location":"Microtubules","reliability":"Additional"},{"location":"Cytokinetic bridge","reliability":"Additional"},{"location":"Primary cilium transition zone","reliability":"Additional"}],"tissue_specificity":"Tissue enriched","tissue_distribution":"Detected in some","driving_tissues":[{"tissue":"adrenal gland","ntpm":2103.4}],"url":"https://www.proteinatlas.org/search/HSD3B2"},"hgnc":{"alias_symbol":["SDR11E2"],"prev_symbol":[]},"alphafold":{"accession":"P26439","domains":[{"cath_id":"3.40.50.720","chopping":"2-191_223-258","consensus_level":"high","plddt":96.2851,"start":2,"end":258}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/P26439","model_url":"https://alphafold.ebi.ac.uk/files/AF-P26439-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-P26439-F1-predicted_aligned_error_v6.png","plddt_mean":94.44},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=HSD3B2","jax_strain_url":"https://www.jax.org/strain/search?query=HSD3B2"},"sequence":{"accession":"P26439","fasta_url":"https://rest.uniprot.org/uniprotkb/P26439.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/P26439/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/P26439"}},"corpus_meta":[{"pmid":"22778212","id":"PMC_22778212","title":"Metformin inhibits human androgen production by regulating steroidogenic enzymes HSD3B2 and CYP17A1 and complex I activity of the respiratory chain.","date":"2012","source":"Endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/22778212","citation_count":87,"is_preprint":false},{"pmid":"10599696","id":"PMC_10599696","title":"New insight into the molecular basis of 3beta-hydroxysteroid dehydrogenase deficiency: identification of eight mutations in the HSD3B2 gene eleven patients from seven new families and comparison of the functional properties of twenty-five mutant enzymes.","date":"1999","source":"The Journal of clinical endocrinology and metabolism","url":"https://pubmed.ncbi.nlm.nih.gov/10599696","citation_count":83,"is_preprint":false},{"pmid":"11912155","id":"PMC_11912155","title":"Joint effect of HSD3B1 and HSD3B2 genes is associated with hereditary and sporadic prostate cancer susceptibility.","date":"2002","source":"Cancer 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homozygous frameshift mutation 273 delta AA in type II 3 beta-hydroxysteroid dehydrogenase gene (HSD3B2) in three male patients of Afghan/Pakistani origin.","date":"1994","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/8004103","citation_count":32,"is_preprint":false},{"pmid":"26465200","id":"PMC_26465200","title":"A Dietary Medium-Chain Fatty Acid, Decanoic Acid, Inhibits Recruitment of Nur77 to the HSD3B2 Promoter In Vitro and Reverses Endocrine and Metabolic Abnormalities in a Rat Model of Polycystic Ovary Syndrome.","date":"2015","source":"Endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/26465200","citation_count":31,"is_preprint":false},{"pmid":"10651755","id":"PMC_10651755","title":"Mutations in the type II 3beta-hydroxysteroid dehydrogenase (HSD3B2) gene can cause premature pubarche in girls.","date":"2000","source":"Clinical 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and sterility","url":"https://pubmed.ncbi.nlm.nih.gov/10973654","citation_count":9,"is_preprint":false},{"pmid":"25322271","id":"PMC_25322271","title":"A novel missense mutation in the HSD3B2 gene, underlying nonsalt-wasting congenital adrenal hyperplasia. new insight into the structure-function relationships of 3β-hydroxysteroid dehidrogenase type II.","date":"2015","source":"The Journal of clinical endocrinology and metabolism","url":"https://pubmed.ncbi.nlm.nih.gov/25322271","citation_count":9,"is_preprint":false},{"pmid":"27082427","id":"PMC_27082427","title":"A New Homozygous Frameshift Mutation in the HSD3B2 Gene in an Apparently Nonconsanguineous Italian Family.","date":"2016","source":"Hormone research in paediatrics","url":"https://pubmed.ncbi.nlm.nih.gov/27082427","citation_count":8,"is_preprint":false},{"pmid":"30029738","id":"PMC_30029738","title":"Mutation of HSD3B2 Gene and Fate of Dehydroepiandrosterone.","date":"2018","source":"Vitamins and hormones","url":"https://pubmed.ncbi.nlm.nih.gov/30029738","citation_count":7,"is_preprint":false},{"pmid":"21340167","id":"PMC_21340167","title":"Structural aspects of the p.P222Q homozygous mutation of HSD3B2 gene in a patient with congenital adrenal hyperplasia.","date":"2010","source":"Arquivos brasileiros de endocrinologia e metabologia","url":"https://pubmed.ncbi.nlm.nih.gov/21340167","citation_count":7,"is_preprint":false},{"pmid":"15291746","id":"PMC_15291746","title":"YY1 binding within the human HSD3B2 gene intron 1 is required for maximal basal promoter activity: identification of YY1 as the 3beta1-A factor.","date":"2004","source":"Journal of molecular endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/15291746","citation_count":6,"is_preprint":false},{"pmid":"25619355","id":"PMC_25619355","title":"[A novel homozygous mutation p.E25X in the HSD3B2 gene causing salt wasting 3β-hydroxysteroid dehydrogenases deficiency in a Chinese pubertal girl: a delayed diagnosis until recurrent ovary cysts].","date":"2014","source":"Zhonghua er ke za zhi = Chinese journal of pediatrics","url":"https://pubmed.ncbi.nlm.nih.gov/25619355","citation_count":6,"is_preprint":false},{"pmid":"33180036","id":"PMC_33180036","title":"Late diagnosis of 3β-Hydroxysteroid dehydrogenase deficiency: the pivotal role of gas chromatography-mass spectrometry urinary steroid metabolome analysis and a novel homozygous nonsense mutation in the HSD3B2 gene.","date":"2020","source":"Journal of pediatric endocrinology & metabolism : JPEM","url":"https://pubmed.ncbi.nlm.nih.gov/33180036","citation_count":6,"is_preprint":false},{"pmid":"27626911","id":"PMC_27626911","title":"Non-Virilizing Congenital Adrenal Hyperplasia in a Female Patient with a Novel HSD3B2 Mutation.","date":"2016","source":"Sexual development : genetics, molecular biology, evolution, endocrinology, embryology, and pathology of sex determination and differentiation","url":"https://pubmed.ncbi.nlm.nih.gov/27626911","citation_count":5,"is_preprint":false},{"pmid":"28703914","id":"PMC_28703914","title":"Hsd3b2 associated in modulating steroid hormone synthesis pathway regulates the differentiation of chicken embryonic stem cells into spermatogonial stem cells.","date":"2017","source":"Journal of cellular biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/28703914","citation_count":5,"is_preprint":false},{"pmid":"29803408","id":"PMC_29803408","title":"Up regulation of the steroid hormone synthesis regulator HSD3B2 is linked to early PSA recurrence in prostate cancer.","date":"2018","source":"Experimental and molecular pathology","url":"https://pubmed.ncbi.nlm.nih.gov/29803408","citation_count":5,"is_preprint":false},{"pmid":"32506065","id":"PMC_32506065","title":"Co-Existence of Congenital Adrenal Hyperplasia and Bartter Syndrome due to Maternal Uniparental Isodisomy of HSD3B2 and CLCNKB Mutations.","date":"2020","source":"Hormone research in paediatrics","url":"https://pubmed.ncbi.nlm.nih.gov/32506065","citation_count":4,"is_preprint":false},{"pmid":"39387578","id":"PMC_39387578","title":"Immunohistochemical expression of CYP11A1, CYP11B, CYP17, and HSD3B2 in functional and nonfunctional canine adrenocortical tumors.","date":"2024","source":"Journal of veterinary internal medicine","url":"https://pubmed.ncbi.nlm.nih.gov/39387578","citation_count":4,"is_preprint":false},{"pmid":"37384334","id":"PMC_37384334","title":"Identification of a novel candidate HSD3B2 gene variant for familial hypospadias by whole-exome sequencing.","date":"2023","source":"Frontiers in genetics","url":"https://pubmed.ncbi.nlm.nih.gov/37384334","citation_count":3,"is_preprint":false},{"pmid":"27670690","id":"PMC_27670690","title":"DNA methylation is not involved in specific down-regulation of HSD3B2, NR4A1 and RARB genes in androgen-secreting cells of human adrenal cortex.","date":"2016","source":"Molecular and cellular endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/27670690","citation_count":2,"is_preprint":false},{"pmid":"37274334","id":"PMC_37274334","title":"High carrier frequency of a nonsense p.Trp230* variant in HSD3B2 gene in Ossetians.","date":"2023","source":"Frontiers in endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/37274334","citation_count":2,"is_preprint":false},{"pmid":"36553457","id":"PMC_36553457","title":"Co-Occurrence of a Pathogenic HSD3B2 Variant and a Duplication on 10q22.3-q23.2 Detected in Newborn Twins with Salt-Wasting Congenital Adrenal Hyperplasia.","date":"2022","source":"Genes","url":"https://pubmed.ncbi.nlm.nih.gov/36553457","citation_count":2,"is_preprint":false},{"pmid":"39839754","id":"PMC_39839754","title":"Ambiguous Genitalia Due to 3β-Hydroxysteroid Dehydrogenase Type 2 Deficiency: Clinical, Genetic, and Functional Characterization of Two Novel HSD3B2 Variants.","date":"2025","source":"JCEM case reports","url":"https://pubmed.ncbi.nlm.nih.gov/39839754","citation_count":2,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":25376,"output_tokens":2960,"usd":0.060264},"stage2":{"model":"claude-opus-4-6","input_tokens":6307,"output_tokens":2761,"usd":0.15084},"total_usd":0.211104,"stage1_batch_id":"msgbatch_01DzrsgVgYngY1hvM3DU1yF2","stage2_batch_id":"msgbatch_01KA9b7iRzKFdhoBUT7vCvSe","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1999,\n      \"finding\": \"HSD3B2 encodes a bifunctional 3β-hydroxysteroid dehydrogenase/Δ5-Δ4-isomerase that converts Δ5-steroids to Δ4-steroids (e.g., DHEA to androstenedione, pregnenolone to progesterone); 25 disease-causing missense mutations were functionally characterized by transient expression in 293 cells with [14C]-DHEA as substrate, revealing that salt-wasting forms result from complete loss of activity while non-salt-losing forms retain partial activity; protein instability was identified as a novel molecular mechanism underlying some mutations.\",\n      \"method\": \"Site-directed mutagenesis, transient expression in 293 cells, in vitro enzyme activity assay with radiolabeled substrate, Northern/Western blot, in vitro transcription/translation in rabbit reticulocyte lysates\",\n      \"journal\": \"The Journal of clinical endocrinology and metabolism\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — large-scale in vitro mutagenesis and functional reconstitution with multiple orthogonal methods across 25 mutants\",\n      \"pmids\": [\"10599696\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"The A10E missense mutation in HSD3B2 (located in the putative NAD-binding domain) abolishes all detectable enzyme activity when expressed in Ad293 cells, demonstrating that Ala10 in the NAD-binding domain is essential for catalytic function.\",\n      \"method\": \"Site-directed mutagenesis, transient expression in Ad293 cells, in vitro enzyme activity assay\",\n      \"journal\": \"The Journal of clinical endocrinology and metabolism\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — direct in vitro functional assay with mutagenesis establishing active-site requirement\",\n      \"pmids\": [\"10843183\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"The transcription factor YY1 binds two distinct sites within HSD3B2 intron 1; binding to the second YY1 site (35 bp downstream of the 3β1-A element) is required for maximal basal HSD3B2 promoter activity, as mutation of this site reduces transcription by ~50%, and complete abrogation of both YY1 sites reduces activity to the level of a construct lacking all of intron 1.\",\n      \"method\": \"Reporter gene (transient transfection) assay, gel shift assay, mutational analysis, competition analysis, anti-YY1 antibody supershift, Western blot\",\n      \"journal\": \"Journal of molecular endocrinology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — multiple orthogonal methods (gel shift, supershift, mutagenesis, reporter assays) in a single study identifying YY1 as the transcriptional activator\",\n      \"pmids\": [\"15291746\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"HSD3B2 and cytochrome b5 (CYB5A) are co-expressed in a subset of human adrenal cortical cells at the zona fasciculata/zona reticularis border; both are required for androstenedione production, as shown by trilostane (HSD3B2 inhibitor) blocking androstenedione output and siRNA knockdown of CYB5A significantly reducing androstenedione in H295R cells.\",\n      \"method\": \"Immunohistochemistry co-localization in human adrenal tissue, pharmacological inhibition with trilostane, siRNA knockdown, cell culture steroid measurement\",\n      \"journal\": \"The Journal of steroid biochemistry and molecular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — direct localization with functional consequence confirmed by two independent loss-of-function approaches (inhibitor + siRNA)\",\n      \"pmids\": [\"21185375\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Metformin inhibits HSD3B2 enzymatic activity (and reduces its expression) in NCI-H295R steroidogenic cells via inhibition of mitochondrial respiratory chain complex I, independently of AMPK signaling; direct complex I inhibition by rotenone similarly inhibits HSD3B2 activity, placing complex I upstream of HSD3B2 activity regulation.\",\n      \"method\": \"In vitro cell-based steroidogenesis assay (NCI-H295R), pharmacological inhibition (metformin, rotenone), Western blot, mRNA quantification, mitochondrial complex I activity assay\",\n      \"journal\": \"Endocrinology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — epistasis established by two independent inhibitors; multiple orthogonal methods including direct complex I activity measurement\",\n      \"pmids\": [\"22778212\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"Decanoic acid (DA) inhibits HSD3B2 transcription and protein expression in NCI-H295R cells by reducing cAMP-stimulated recruitment of the orphan nuclear receptor Nur77 to the HSD3B2 promoter, thereby decreasing androgen biosynthesis; this mechanism requires cAMP pathway activation.\",\n      \"method\": \"Cell-based steroidogenesis assay, chromatin immunoprecipitation (Nur77 recruitment to HSD3B2 promoter), RT-PCR, Western blot, in vivo rat PCOS model validation\",\n      \"journal\": \"Endocrinology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — ChIP identifying specific transcription factor recruitment to HSD3B2 promoter, validated in vitro and in vivo\",\n      \"pmids\": [\"26465200\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"GATA-binding factor 1 (GATA1) is a transcriptional activator of the HSD3B2 promoter in steroidogenic cells; baicalin inhibits HSD3B2 expression and androgen production by reducing GATA1 recruitment to the HSD3B2 promoter, as established by dual luciferase reporter assay, RNA interference of GATA1, and promoter mutation studies.\",\n      \"method\": \"Gene expression profiling, dual luciferase reporter assay, RNA interference, site-directed mutagenesis of HSD3B2 promoter, ELISA for testosterone, in vivo PCOS rat model\",\n      \"journal\": \"The Journal of endocrinology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — multiple orthogonal approaches (reporter assay, RNAi, mutagenesis) identifying GATA1 as direct HSD3B2 promoter transactivator\",\n      \"pmids\": [\"30650063\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Two novel HSD3B2 missense mutations (p.Y190C and p.S218P), located adjacent to the predicted substrate-binding pocket in 3D homology modeling, severely impair enzyme activity in vitro but retain higher residual activity toward 17-OH pregnenolone than toward other Δ5-steroids, suggesting these residues influence substrate-binding affinity differentially for distinct substrates.\",\n      \"method\": \"Site-directed mutagenesis, in vitro enzyme activity assay in transfected cells, 3D homology modeling\",\n      \"journal\": \"Clinical endocrinology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 — in vitro functional assay with mutagenesis, but single lab and novel substrate-selectivity observation not independently replicated\",\n      \"pmids\": [\"24372086\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"The p.G250V HSD3B2 mutation reduces Vmax for progesterone synthesis (to ~20–27% of wild-type) without altering Km for pregnenolone and without affecting protein expression or intracellular localization; homology modeling places G250 in the L239-Q251 loop adjacent to a β-sheet in the NAD+-binding domain, suggesting this loop is important for catalytic activity.\",\n      \"method\": \"In vitro enzyme activity assay in COS-7 cells (Vmax/Km kinetics), Western blot, immunofluorescence, molecular homology modeling\",\n      \"journal\": \"The Journal of clinical endocrinology and metabolism\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 — kinetic characterization with mutagenesis plus structural modeling; single-lab study\",\n      \"pmids\": [\"25322271\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Sunitinib inhibits HSD3B2 in adrenocortical cells by down-regulating HSD3B2 mRNA and protein (not by direct enzymatic inhibition), as demonstrated by steroid profiling showing accumulation of HSD3B2 substrates, absence of direct inhibition in yeast microsomes expressing HSD3B2, and dose-dependent reduction of HSD3B2 mRNA/protein in NCI-H295R cells.\",\n      \"method\": \"Gas chromatography-mass spectrometry steroid profiling, yeast microsome HSD3B2 direct inhibition assay, RT-PCR, Western blot in ACC cell lines\",\n      \"journal\": \"Frontiers in endocrinology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods distinguishing indirect (transcriptional) from direct enzymatic inhibition\",\n      \"pmids\": [\"22654799\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"DNA methylation is not the mechanism responsible for zone-specific down-regulation of HSD3B2 in the human adrenal zona reticularis, as HSD3B2 lacks CpG islands, and bisulfite/methylation analysis did not reveal adrenal zone-specific differences.\",\n      \"method\": \"RT-qPCR on microdissected adrenal zones, methylation analysis, CpG island analysis\",\n      \"journal\": \"Molecular and cellular endocrinology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — direct epigenetic analysis with microdissected tissue; single lab, mechanistically informative negative result\",\n      \"pmids\": [\"27670690\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"HSD3B2 encodes a bifunctional NAD+-dependent microsomal enzyme (3β-hydroxysteroid dehydrogenase/Δ5-Δ4-isomerase) that catalyzes conversion of Δ5-steroids to Δ4-steroids in adrenals and gonads; its catalytic activity depends on an intact NAD+-binding domain (including Ala10 and the L239-Q251 loop), and its expression is transcriptionally activated by YY1 (via intron 1 elements) and GATA1 (via the proximal promoter), while being suppressed by inhibition of mitochondrial complex I (as occurs with metformin), reduced Nur77 recruitment (by decanoic acid), or reduced GATA1 recruitment (by baicalin); co-expression with CYB5A in zona fasciculata/reticularis border cells is required for adrenal androstenedione production.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"HSD3B2 encodes a bifunctional NAD⁺-dependent microsomal 3β-hydroxysteroid dehydrogenase/Δ5→Δ4-isomerase that catalyzes the obligatory conversion of Δ5-steroids (pregnenolone, DHEA, 17-OH pregnenolone) to their Δ4-products (progesterone, androstenedione, 17-OH progesterone), a rate-limiting step in adrenal and gonadal steroidogenesis [PMID:10599696]. Catalytic competence requires an intact NAD⁺-binding domain — Ala10 is essential for all detectable activity, and the L239–Q251 loop modulates Vmax without affecting substrate affinity — while mutations near the substrate-binding pocket differentially impair conversion of individual Δ5-substrates [PMID:10843183, PMID:25322271, PMID:24372086]. Transcription of HSD3B2 is positively regulated by YY1 (via intron 1 elements), GATA1 (via the proximal promoter), and Nur77 (recruited upon cAMP stimulation), while mitochondrial complex I inhibition by metformin or rotenone suppresses both expression and activity independently of AMPK [PMID:15291746, PMID:30650063, PMID:26465200, PMID:22778212]. Loss-of-function mutations cause 3β-hydroxysteroid dehydrogenase deficiency, a form of congenital adrenal hyperplasia in which complete activity loss produces salt-wasting disease and partial activity loss produces a non-salt-losing phenotype [PMID:10599696].\",\n  \"teleology\": [\n    {\n      \"year\": 1999,\n      \"claim\": \"Systematic functional characterization of 25 disease-causing HSD3B2 missense mutations established that the degree of residual enzyme activity directly determines clinical severity (salt-wasting vs. non-salt-losing congenital adrenal hyperplasia) and identified protein instability as a novel pathogenic mechanism, transforming genotype–phenotype understanding.\",\n      \"evidence\": \"Site-directed mutagenesis with transient expression in 293 cells using [¹⁴C]-DHEA substrate conversion, Northern/Western blot, and in vitro translation\",\n      \"pmids\": [\"10599696\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Structural basis for instability of specific mutant proteins not determined\",\n        \"Residual activity measured in heterologous cells may not reflect in vivo adrenal/gonadal context\"\n      ]\n    },\n    {\n      \"year\": 2000,\n      \"claim\": \"Demonstration that the A10E mutation in the NAD⁺-binding domain abolishes all catalytic activity established Ala10 as essential for cofactor binding and enzyme function, pinpointing the cofactor-binding domain as a critical determinant of HSD3B2 activity.\",\n      \"evidence\": \"Site-directed mutagenesis and enzyme activity assay in transfected Ad293 cells\",\n      \"pmids\": [\"10843183\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"No crystal structure or direct cofactor-binding measurement to confirm NAD⁺ interaction at Ala10\",\n        \"Other residues in the NAD⁺-binding domain not systematically tested\"\n      ]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Identification of YY1 as a transcription factor binding two sites in intron 1 and required for maximal basal HSD3B2 promoter activity provided the first defined cis-regulatory mechanism for HSD3B2 expression.\",\n      \"evidence\": \"Gel shift, antibody supershift, mutagenesis of YY1 sites, and reporter gene assays\",\n      \"pmids\": [\"15291746\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Cell type-specific relevance of YY1 in adrenal vs. gonadal tissues not tested\",\n        \"Chromatin-level confirmation (e.g., ChIP) was not performed\"\n      ]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Co-localization of HSD3B2 and CYB5A at the zona fasciculata/reticularis border, combined with loss-of-function experiments, established that androstenedione production in the adrenal requires cooperative activity of both enzymes, explaining zonal heterogeneity in adrenal androgen output.\",\n      \"evidence\": \"Immunohistochemistry on human adrenal tissue, trilostane inhibition, and siRNA knockdown of CYB5A in H295R cells\",\n      \"pmids\": [\"21185375\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Whether HSD3B2 and CYB5A physically interact or function independently at the same membrane is unknown\",\n        \"Mechanism establishing their co-expression in border-zone cells not identified\"\n      ]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Metformin and rotenone both inhibit HSD3B2 expression and activity via mitochondrial complex I inhibition (independently of AMPK), revealing an unexpected link between mitochondrial electron transport and steroidogenic gene regulation.\",\n      \"evidence\": \"Pharmacological inhibition with metformin and rotenone in NCI-H295R cells, complex I activity assay, Western blot, mRNA quantification\",\n      \"pmids\": [\"22778212\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Signaling intermediates between complex I and HSD3B2 transcription/activity not identified\",\n        \"Relevance to in vivo adrenal steroidogenesis during metformin therapy not confirmed in human tissue\"\n      ]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Novel mutations (Y190C, S218P) near the modeled substrate-binding pocket showed substrate-selective impairment, retaining higher residual activity for 17-OH pregnenolone than other Δ5-steroids, revealing that distinct residues contribute differentially to binding of individual substrates.\",\n      \"evidence\": \"Site-directed mutagenesis, enzyme activity assay in transfected cells, 3D homology modeling\",\n      \"pmids\": [\"24372086\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Substrate selectivity based on homology model without experimental structural validation\",\n        \"Observation from a single lab, not independently replicated\",\n        \"Kinetic parameters (Km, Vmax) for each substrate not fully determined\"\n      ]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Kinetic characterization of the G250V mutation showed reduced Vmax without altered Km or mislocalization, identifying the L239–Q251 loop as important for catalytic turnover rather than substrate recognition, and decanoic acid was shown to suppress HSD3B2 transcription by blocking Nur77 recruitment to the promoter, adding Nur77 to the roster of direct HSD3B2 transcriptional regulators.\",\n      \"evidence\": \"Enzyme kinetics in COS-7 cells with homology modeling (G250V); ChIP for Nur77 at HSD3B2 promoter, RT-PCR, Western blot in H295R cells with in vivo PCOS rat validation (decanoic acid)\",\n      \"pmids\": [\"25322271\", \"26465200\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"No crystal structure to confirm loop conformation or catalytic mechanism\",\n        \"Nur77 ChIP performed only in H295R cells; relevance across steroidogenic tissues unknown\"\n      ]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Ruling out DNA methylation as the mechanism for zona reticularis-specific HSD3B2 down-regulation narrowed the search for the epigenetic or trans-acting factor responsible for adrenal zonal expression patterning.\",\n      \"evidence\": \"Bisulfite sequencing and methylation analysis on microdissected human adrenal zones\",\n      \"pmids\": [\"27670690\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Alternative epigenetic marks (histone modifications, chromatin accessibility) not examined\",\n        \"Single-lab study on limited number of adrenal specimens\",\n        \"The actual mechanism of zone-specific silencing remains unidentified\"\n      ]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Identification of GATA1 as a direct transcriptional activator of HSD3B2 — binding the proximal promoter and being required for basal expression — completed a picture of three distinct positive regulators (YY1, Nur77, GATA1) acting at different promoter/intronic elements.\",\n      \"evidence\": \"Dual luciferase reporter assay, GATA1 RNAi, HSD3B2 promoter site-directed mutagenesis, in vivo PCOS rat model\",\n      \"pmids\": [\"30650063\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Combinatorial or hierarchical relationships among YY1, Nur77, and GATA1 at the HSD3B2 locus not established\",\n        \"GATA1 role validated primarily in H295R cells; relevance to gonadal HSD3B2 expression unknown\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"An experimentally determined three-dimensional structure for HSD3B2 is lacking, and the mechanism by which mitochondrial complex I status is transduced to HSD3B2 transcriptional regulation remains unknown; additionally, the cis-regulatory logic governing adrenal zone-specific silencing has not been identified.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"No crystal or cryo-EM structure available\",\n        \"Signaling pathway from complex I to HSD3B2 transcription undefined\",\n        \"Mechanism of zona reticularis-specific HSD3B2 silencing unresolved\",\n        \"Combinatorial regulation by YY1, Nur77, and GATA1 not integrated\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016491\", \"supporting_discovery_ids\": [0, 1, 7, 8]},\n      {\"term_id\": \"GO:0016853\", \"supporting_discovery_ids\": [0, 7]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005783\", \"supporting_discovery_ids\": [3, 8]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [0, 1, 3, 7, 8]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\n      \"CYB5A\",\n      \"YY1\",\n      \"GATA1\",\n      \"NR4A1\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}