{"gene":"DUOX2","run_date":"2026-06-09T23:54:42","timeline":{"discoveries":[{"year":1999,"finding":"DUOX2 (p138(Tox)) was purified from pig thyroid plasma membrane as a flavoprotein that constitutes the main component of the thyroid Ca2+-dependent NAD(P)H oxidase, transferring electrons from NAD(P)H to molecular oxygen to generate H2O2. The protein contains FAD- and NADPH-binding site consensus sequences and two N-terminal EF-hand motifs that account for its calcium-dependent activity.","method":"Protein purification from pig thyroid plasma membrane, microsequencing, cDNA cloning, domain analysis","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — direct biochemical purification of the enzyme and identification of catalytic domains, replicated by subsequent cloning studies","pmids":["10601291"],"is_preprint":false},{"year":2000,"finding":"DUOX2 (ThOX2) encodes a 1548-amino acid NADPH oxidase family member (theoretical MW 177 kDa, apparent 180 kDa) that accumulates at the apical membrane of thyrocytes co-localized with thyroperoxidase, and its mRNA expression is thyroid-specific and up-regulated by agents activating the cAMP pathway.","method":"Low-stringency cDNA library screening, Western blot, immunolocalization, Northern blot, chromosome mapping","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (cloning, Western blot, localization), replicated across two independent groups","pmids":["10806195"],"is_preprint":false},{"year":2002,"finding":"DUOX2 (ThOX2) is a glycoprotein of ~180–190 kDa; deglycosylation reduces both ThOX1 and ThOX2 to ~160 kDa. The majority of ThOX protein accumulates intracellularly and only a small fraction reaches the cell surface. The intracellularly retained 'immature' form is enzymatically inactive. Ca2+ stimulates H2O2 generation in thyroid cells expressing ThOX. Co-expression with thyroperoxidase or p22(Phox) does not rescue surface expression or activity of ThOX in non-thyroid cells, indicating that additional thyroid-specific factors are required for full processing and enzymatic activity.","method":"Western blot, deglycosylation assay, H2O2 generation assay, transfection of non-thyroid cell lines, complementation assay in PLB-XCGD cells","journal":"Experimental cell research","confidence":"High","confidence_rationale":"Tier 1–2 / Moderate — multiple orthogonal biochemical methods in one study with direct enzymatic readout and negative complementation controls","pmids":["11822874"],"is_preprint":false},{"year":2001,"finding":"DUOX2 (LNOX2) protein is a ~164-kDa glycoprotein in human thyroid membrane fractions, with N-glycosylation accounting for at least 10–20 kDa of its apparent molecular mass. The protein is localized at the apical pole of thyrocytes and its mRNA is strongly and specifically expressed in thyroid tissue.","method":"Western blot with antipeptide antibodies, Northern blot across 23 tissues, immunostaining, quantitative PCR","journal":"The Journal of clinical endocrinology and metabolism","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple methods (Western blot, Northern blot, immunostaining) in a single lab","pmids":["11443211"],"is_preprint":false},{"year":2002,"finding":"Biallelic (homozygous) nonsense mutations in DUOX2 (THOX2) result in complete loss of all functional protein domains and cause severe permanent congenital hypothyroidism with complete iodide-organification defect. Monoallelic (heterozygous) truncating mutations cause milder transient congenital hypothyroidism due to insufficient H2O2 production, establishing DUOX2 as the rate-limiting H2O2-generating enzyme for thyroid hormone synthesis.","method":"DNA sequencing of patients and relatives, mutational analysis of THOX1 and THOX2 genes, genotype-phenotype correlation","journal":"The New England journal of medicine","confidence":"High","confidence_rationale":"Tier 2 / Strong — human genetic loss-of-function with clear dose-dependent phenotype replicated across multiple families and independently confirmed","pmids":["12110737"],"is_preprint":false},{"year":2004,"finding":"The THOX2 gene spans 75 kb and is composed of 34 exons, arranged in a head-to-head configuration with THOX1 separated by a 16 kb intergenic region. Functional studies show that the THOX2 promoter drives transcriptional activity in differentiated thyroid cells but is not positively regulated by cAMP and is not restricted to thyroid cells in transfection assays.","method":"Genomic sequencing, exon mapping, promoter-reporter transfection assays in thyroid cell lines","journal":"Molecular and cellular endocrinology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct functional promoter assays combined with genomic structure determination in a single study","pmids":["15062544"],"is_preprint":false},{"year":2010,"finding":"THOX2 and DUOXA2 genes are arranged in a head-to-head configuration sharing a bidirectional promoter region. The THOX2 transcription start is separated from DUOXA2 by only 170 bp. The intergenic region contains a TATA box and an Inr element and drives bidirectional promoter activity in thyroid PCCl3 cells, functionally linking DUOX2 expression to its maturation factor DUOXA2 at the transcriptional level.","method":"RLM-RACE (transcription start mapping), bidirectional reporter transfection assays in PCCl3 thyroid cells, gel shift assays","journal":"Molecular and cellular endocrinology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct functional promoter assays and transcription start mapping with multiple methods in a single lab","pmids":["20060878"],"is_preprint":false},{"year":2024,"finding":"In the intestinal epithelium, DUOX2 and its maturation factor DUOXA2 are induced by C. albicans colonization in an IL-17 receptor-dependent manner; IL-17A addition to colonoids directly induces DUOX2/DUOXA2 and H2O2 production. Loss of intestinal DUOX2 function reduced C. albicans colonization at extended timepoints (>17 days) and increased the proportion of hyphal cells, while elevating IL-17A levels, revealing a feedback regulatory axis between IL-17 signaling and DUOX2-mediated H2O2 production that controls fungal filamentation and colonization.","method":"Expression profiling in germ-free mice colonized with C. albicans, IL-17 receptor knockout mice, colonoid IL-17A treatment with H2O2 measurement, intestinal DUOX2-knockout mouse colonization assay","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal in vivo and ex vivo methods in a single preprint study, not yet peer-reviewed","pmids":[],"is_preprint":true},{"year":2025,"finding":"Social disruption stress upregulates Duox2 and Duoxa2 expression 2- to 8-fold in intestinal epithelial cells via β-adrenergic receptor signaling; this upregulation is reversed by β-AR blockade (propranolol) but not by α2-adrenergic, glucocorticoid receptor, or CRHR1 antagonism. NADPH oxidase inhibition with apocynin mitigated stress-induced ROS/RNS production and colitis severity, placing DUOX2 downstream of β-adrenergic signaling in stress-induced intestinal oxidative stress.","method":"Pharmacological antagonist pretreatment in SDR stress mouse model, IEC gene expression analysis, apocynin intervention in infectious and chemical colitis models","journal":"bioRxiv","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single preprint, pharmacological (not genetic) dissection of pathway, indirect evidence for DUOX2 as β-adrenergic effector","pmids":[],"is_preprint":true},{"year":2024,"finding":"During neonatal colon development, functional sentinel goblet cell secretory responses are dependent on DUOX2 (a NADPH/Dual oxidase family member), as demonstrated by ex vivo analyses showing that DUOX2 loss impairs microbiota-dependent maturation of sentinel goblet cell function.","method":"In vivo and ex vivo analyses of pre- and post-weaning colonic goblet cell function in Duox2-deficient mice","journal":"bioRxiv","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single preprint, phenotypic description of Duox2-deficient mice with limited mechanistic resolution in the abstract","pmids":[],"is_preprint":true}],"current_model":"DUOX2 is a Ca2+-dependent, FAD- and NADPH-binding flavoprotein NADPH oxidase that localizes to the apical membrane of thyrocytes, where it generates H2O2 as the rate-limiting oxidant for thyroperoxidase-catalyzed iodide organification and thyroid hormone synthesis; its trafficking to the plasma membrane and enzymatic activation require additional thyroid-specific maturation factors (including DUOXA2, encoded by a co-regulated head-to-head promoter), and in the intestinal epithelium it is activated downstream of IL-17 and β-adrenergic signaling to produce reactive oxygen species that regulate microbial colonization and barrier function."},"narrative":{"mechanistic_narrative":"DUOX2 is a Ca2+-dependent, FAD- and NADPH-binding flavoprotein NADPH oxidase that transfers electrons from NAD(P)H to molecular oxygen to generate H2O2, serving as the rate-limiting oxidant source for thyroid hormone synthesis [PMID:10601291, PMID:12110737]. The enzyme harbors FAD- and NADPH-binding consensus sequences and two N-terminal EF-hand motifs that confer calcium-dependent H2O2 production [PMID:10601291]. In thyrocytes it accumulates at the apical membrane co-localized with thyroperoxidase, providing the H2O2 required for iodide organification, and its expression is thyroid-specific and up-regulated through the cAMP pathway [PMID:10806195]. DUOX2 is a heavily N-glycosylated ~180–190 kDa protein whose immature, intracellularly retained form is enzymatically inactive; full surface expression and activity cannot be rescued by thyroperoxidase or p22(phox) alone, indicating a requirement for additional thyroid-specific maturation factors [PMID:11822874]. This requirement is met by DUOXA2, whose gene lies in a head-to-head configuration with DUOX2 sharing a bidirectional promoter, functionally coupling the oxidase to its maturation factor at the transcriptional level [PMID:20060878]. Biallelic nonsense mutations in DUOX2 cause severe permanent congenital hypothyroidism with complete iodide-organification defect, while heterozygous truncating mutations cause milder transient hypothyroidism, establishing DUOX2 as the dose-limiting H2O2-generating enzyme of thyroid hormone biogenesis [PMID:12110737]. Beyond the thyroid, DUOX2 and DUOXA2 are induced in intestinal epithelium downstream of IL-17 receptor signaling, where DUOX2-derived H2O2 restrains Candida albicans filamentation and colonization in an IL-17 feedback axis.","teleology":[{"year":1999,"claim":"Established the biochemical identity of DUOX2 as the catalytic flavoprotein of the thyroid Ca2+-dependent NAD(P)H oxidase, answering what enzyme generates thyroid H2O2.","evidence":"Protein purification from pig thyroid plasma membrane with microsequencing, cDNA cloning, and domain analysis","pmids":["10601291"],"confidence":"High","gaps":["Did not resolve the membrane topology or how electrons traverse the protein to oxygen","Maturation/trafficking partners not identified"]},{"year":2000,"claim":"Defined DUOX2 as a thyroid-specific apical-membrane oxidase co-localized with thyroperoxidase and regulated by cAMP, linking its expression to thyroid hormone synthesis.","evidence":"cDNA library screening, Western blot, immunolocalization, Northern blot, and chromosome mapping","pmids":["10806195"],"confidence":"High","gaps":["Mechanism of apical targeting unresolved","Functional coupling to thyroperoxidase shown by colocalization only"]},{"year":2001,"claim":"Confirmed DUOX2 as a glycosylated apical thyroid membrane protein with strictly thyroid-restricted mRNA, reinforcing its tissue-specific role.","evidence":"Western blot with antipeptide antibodies, Northern blot across 23 tissues, immunostaining, qPCR","pmids":["11443211"],"confidence":"Medium","gaps":["Single-lab characterization","Functional H2O2 readout not assessed"]},{"year":2002,"claim":"Showed that the intracellular immature form is inactive and that surface expression requires thyroid-specific factors beyond thyroperoxidase or p22(phox), predicting a dedicated maturation factor.","evidence":"Deglycosylation assays, H2O2 generation assays, and complementation in non-thyroid and PLB-XCGD cells","pmids":["11822874"],"confidence":"High","gaps":["The specific thyroid maturation factor not yet identified","Step at which trafficking is blocked unresolved"]},{"year":2002,"claim":"Demonstrated by human genetics that DUOX2 is the rate-limiting, dose-dependent H2O2 source for thyroid hormone synthesis, with biallelic loss causing permanent and monoallelic loss causing transient congenital hypothyroidism.","evidence":"DNA sequencing and genotype-phenotype correlation across patients and families","pmids":["12110737"],"confidence":"High","gaps":["Does not address modifier genes governing transient versus permanent phenotype","Compensation by DUOX1 not fully delineated"]},{"year":2004,"claim":"Determined genomic structure and promoter behavior, showing the DUOX2 promoter is active in differentiated thyroid cells but not directly cAMP-responsive or thyroid-restricted in transfection assays.","evidence":"Genomic sequencing, exon mapping, and promoter-reporter transfection in thyroid cell lines","pmids":["15062544"],"confidence":"Medium","gaps":["Reporter assays may not recapitulate native chromatin regulation","Trans-acting factors driving thyroid specificity not identified"]},{"year":2010,"claim":"Revealed that DUOX2 and its maturation factor DUOXA2 share a bidirectional promoter, providing a transcriptional mechanism for co-regulating oxidase and maturation factor expression.","evidence":"RLM-RACE transcription start mapping, bidirectional reporter assays in PCCl3 cells, and gel shift assays","pmids":["20060878"],"confidence":"Medium","gaps":["Specific transcription factors binding the bidirectional promoter not defined","In vivo relevance of co-regulation not tested genetically"]},{"year":2024,"claim":"Extended DUOX2 function to the intestinal epithelium, placing it downstream of IL-17 receptor signaling in an H2O2-mediated feedback axis that controls Candida albicans filamentation and colonization.","evidence":"Germ-free colonization, IL-17R knockout mice, colonoid IL-17A treatment with H2O2 measurement, and intestinal DUOX2-knockout colonization assays (preprint)","pmids":[],"confidence":"Medium","gaps":["Preprint, not yet peer-reviewed","Direct molecular link between IL-17R signaling and DUOX2 induction not mapped","Whether H2O2 acts directly on hyphae or via host cells unresolved"]},{"year":2025,"claim":"Positioned DUOX2 as a candidate effector of β-adrenergic stress signaling driving intestinal oxidative stress and colitis severity.","evidence":"Pharmacological antagonist pretreatment in a social-disruption stress mouse model with apocynin intervention in colitis (preprint)","pmids":[],"confidence":"Low","gaps":["Single preprint with pharmacological rather than genetic dissection","Apocynin inhibits NADPH oxidases broadly, not DUOX2 specifically","Direct β-AR-to-DUOX2 signaling link not established"]},{"year":2024,"claim":"Implicated DUOX2 in microbiota-dependent maturation of neonatal sentinel goblet cell secretory function.","evidence":"In vivo and ex vivo analyses of colonic goblet cell function in Duox2-deficient mice (preprint)","pmids":[],"confidence":"Low","gaps":["Single preprint with limited mechanistic resolution","Molecular mediator linking DUOX2 H2O2 to goblet cell function not identified"]},{"year":null,"claim":"How DUOX2-derived H2O2 is spatially and temporally controlled across thyroid versus mucosal contexts, and the upstream signaling that gates its activity in the intestine, remain open.","evidence":"No direct experimental resolution in the available corpus","pmids":[],"confidence":"Low","gaps":["Structural basis of electron transfer not determined","Intestinal regulatory axes rest on preprint evidence only"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016491","term_label":"oxidoreductase activity","supporting_discovery_ids":[0,2]}],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[0,1,3]}],"pathway":[],"complexes":[],"partners":["DUOXA2"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9NRD8","full_name":"Dual oxidase 2","aliases":["Large NOX 2","Long NOX 2","NADH/NADPH thyroid oxidase p138-tox","NADPH oxidase/peroxidase DUOX2","NADPH thyroid oxidase 2","Thyroid oxidase 2","p138 thyroid oxidase"],"length_aa":1548,"mass_kda":175.4,"function":"Generates hydrogen peroxide which is required for the activity of thyroid peroxidase/TPO and lactoperoxidase/LPO (PubMed:15972824). Plays a role in thyroid hormone synthesis. Also required for lactoperoxidase-mediated antimicrobial defense at the surface of mucosa (PubMed:12824283). Synthesizes NAADP from its reduced NAADPH form which promotes Ca(2+) signaling during T cell activation (PubMed:34784249). May have its own peroxidase activity through its N-terminal peroxidase-like domain","subcellular_location":"Apical cell membrane; Cell junction","url":"https://www.uniprot.org/uniprotkb/Q9NRD8/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/DUOX2","classification":"Not Classified","n_dependent_lines":18,"n_total_lines":1208,"dependency_fraction":0.014900662251655629},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/DUOX2","total_profiled":1310},"omim":[{"mim_id":"617792","title":"THIOREDOXIN DOMAIN-CONTAINING PROTEIN 11; TXNDC11","url":"https://www.omim.org/entry/617792"},{"mim_id":"612772","title":"DUAL OXIDASE MATURATION FACTOR 2; DUOXA2","url":"https://www.omim.org/entry/612772"},{"mim_id":"612771","title":"DUAL OXIDASE MATURATION FACTOR 1; DUOXA1","url":"https://www.omim.org/entry/612771"},{"mim_id":"609893","title":"HYPOTHYROIDISM, CONGENITAL, NONGOITROUS, 3; CHNG3","url":"https://www.omim.org/entry/609893"},{"mim_id":"607200","title":"THYROID DYSHORMONOGENESIS 6; TDH6","url":"https://www.omim.org/entry/607200"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in many","driving_tissues":[{"tissue":"gallbladder","ntpm":273.1},{"tissue":"thyroid gland","ntpm":70.8},{"tissue":"urinary bladder","ntpm":86.8}],"url":"https://www.proteinatlas.org/search/DUOX2"},"hgnc":{"alias_symbol":["P138-TOX","P138(TOX)","THOX2","LNOX2"],"prev_symbol":[]},"alphafold":{"accession":"Q9NRD8","domains":[{"cath_id":"1.10.640.10","chopping":"56-555","consensus_level":"medium","plddt":93.6057,"start":56,"end":555},{"cath_id":"2.30.29.140","chopping":"643-753","consensus_level":"high","plddt":81.1881,"start":643,"end":753},{"cath_id":"1.10.238","chopping":"762-854","consensus_level":"medium","plddt":73.1728,"start":762,"end":854},{"cath_id":"1.10.238.10","chopping":"856-937","consensus_level":"medium","plddt":68.437,"start":856,"end":937},{"cath_id":"-","chopping":"1068-1267","consensus_level":"high","plddt":91.7651,"start":1068,"end":1267},{"cath_id":"2.40.30.10","chopping":"1268-1371","consensus_level":"medium","plddt":83.7622,"start":1268,"end":1371},{"cath_id":"3.40.50.80","chopping":"1372-1548","consensus_level":"medium","plddt":85.4995,"start":1372,"end":1548}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9NRD8","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9NRD8-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9NRD8-F1-predicted_aligned_error_v6.png","plddt_mean":83.94},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=DUOX2","jax_strain_url":"https://www.jax.org/strain/search?query=DUOX2"},"sequence":{"accession":"Q9NRD8","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9NRD8.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9NRD8/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9NRD8"}},"corpus_meta":[{"pmid":"10806195","id":"PMC_10806195","title":"Cloning of two human thyroid cDNAs encoding new members of the NADPH oxidase family.","date":"2000","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/10806195","citation_count":479,"is_preprint":false},{"pmid":"12110737","id":"PMC_12110737","title":"Inactivating mutations in the gene for thyroid oxidase 2 (THOX2) and congenital hypothyroidism.","date":"2002","source":"The New England journal of medicine","url":"https://pubmed.ncbi.nlm.nih.gov/12110737","citation_count":366,"is_preprint":false},{"pmid":"10601291","id":"PMC_10601291","title":"Purification of a novel flavoprotein involved in the thyroid NADPH oxidase. Cloning of the porcine and human cdnas.","date":"1999","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/10601291","citation_count":356,"is_preprint":false},{"pmid":"15863666","id":"PMC_15863666","title":"Genetics of congenital hypothyroidism.","date":"2005","source":"Journal of medical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/15863666","citation_count":264,"is_preprint":false},{"pmid":"11822874","id":"PMC_11822874","title":"Characterization of ThOX proteins as components of the thyroid H(2)O(2)-generating system.","date":"2002","source":"Experimental cell research","url":"https://pubmed.ncbi.nlm.nih.gov/11822874","citation_count":147,"is_preprint":false},{"pmid":"11443211","id":"PMC_11443211","title":"Expression of reduced nicotinamide adenine dinucleotide phosphate oxidase (ThoX, LNOX, Duox) genes and proteins in human thyroid tissues.","date":"2001","source":"The Journal of clinical endocrinology and metabolism","url":"https://pubmed.ncbi.nlm.nih.gov/11443211","citation_count":93,"is_preprint":false},{"pmid":"15062544","id":"PMC_15062544","title":"Structural and functional characterization of the two human ThOX/Duox genes and their 5'-flanking regions.","date":"2004","source":"Molecular and cellular endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/15062544","citation_count":64,"is_preprint":false},{"pmid":"17121535","id":"PMC_17121535","title":"Congenital hypothyroidism caused by new mutations in the thyroid oxidase 2 (THOX2) gene.","date":"2006","source":"Clinical endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/17121535","citation_count":45,"is_preprint":false},{"pmid":"14751036","id":"PMC_14751036","title":"Thyroperoxidase gene mutations in congenital goitrous hypothyroidism with total and partial iodide organification defect.","date":"2003","source":"Thyroid : official journal of the American Thyroid Association","url":"https://pubmed.ncbi.nlm.nih.gov/14751036","citation_count":45,"is_preprint":false},{"pmid":"21835056","id":"PMC_21835056","title":"Molecules important for thyroid hormone synthesis and action - known facts and future perspectives.","date":"2011","source":"Thyroid research","url":"https://pubmed.ncbi.nlm.nih.gov/21835056","citation_count":39,"is_preprint":false},{"pmid":"20060878","id":"PMC_20060878","title":"Delimitation and functional characterization of the bidirectional THOX-DUOXA promoter regions in thyrocytes.","date":"2010","source":"Molecular and cellular endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/20060878","citation_count":24,"is_preprint":false},{"pmid":"15611819","id":"PMC_15611819","title":"[Genetic aspects in congenital hypothyrodism].","date":"2004","source":"Arquivos brasileiros de endocrinologia e metabologia","url":"https://pubmed.ncbi.nlm.nih.gov/15611819","citation_count":3,"is_preprint":false},{"pmid":"32207419","id":"PMC_32207419","title":"Insilico study of genes involved in Congenital Hypothyroidism.","date":"2020","source":"JPMA. The Journal of the Pakistan Medical Association","url":"https://pubmed.ncbi.nlm.nih.gov/32207419","citation_count":1,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.07.15.664961","title":"Social stress worsens colitis through β-adrenergic–driven oxidative stress in intestinal mucosal compartments","date":"2025-07-18","source":"bioRxiv","url":"https://doi.org/10.1101/2025.07.15.664961","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.08.16.608271","title":"An IL-17-DUOX2 axis controls gastrointestinal colonization by  <i>Candida albicans</i>","date":"2024-08-19","source":"bioRxiv","url":"https://doi.org/10.1101/2024.08.16.608271","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.07.03.601781","title":"Neonatal microbiota colonization drives maturation of primary and secondary goblet cell mediated protection in the pre-weaning colon","date":"2024-07-05","source":"bioRxiv","url":"https://doi.org/10.1101/2024.07.03.601781","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.08.27.25333852","title":"Ultrarare Variants in DNA Damage Repair and Mitochondrial Genes in Pediatric Acute-Onset Neuropsychiatric Syndrome and Acute Behavioral Regression in Neurodevelopmental Disorders","date":"2025-08-27","source":"bioRxiv","url":"https://doi.org/10.1101/2025.08.27.25333852","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.09.08.674949","title":"TNF signaling drives expansion of Reg4+ epithelial cells in colitis","date":"2025-09-09","source":"bioRxiv","url":"https://doi.org/10.1101/2025.09.08.674949","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.12.04.626838","title":"Multi-omics analysis of the mechanism of alfalfa and wheat-induced rumen flatulence in Xizang sheep","date":"2024-12-04","source":"bioRxiv","url":"https://doi.org/10.1101/2024.12.04.626838","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.07.23.24310848","title":"Inflammatory Bowel Disease in patients with Primary Sclerosing Cholangitis: a distinct form of colitis","date":"2024-07-23","source":"bioRxiv","url":"https://doi.org/10.1101/2024.07.23.24310848","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":13140,"output_tokens":2767,"usd":0.040462,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":10056,"output_tokens":3290,"usd":0.066265,"stage2_stop_reason":"end_turn"},"total_usd":0.106727,"stage1_batch_id":"msgbatch_01AsR7g8dGTEiEw9U83bJeWn","stage2_batch_id":"msgbatch_01YV5ZyxtFNUZEjxRcpd9jzb","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1999,\n      \"finding\": \"DUOX2 (p138(Tox)) was purified from pig thyroid plasma membrane as a flavoprotein that constitutes the main component of the thyroid Ca2+-dependent NAD(P)H oxidase, transferring electrons from NAD(P)H to molecular oxygen to generate H2O2. The protein contains FAD- and NADPH-binding site consensus sequences and two N-terminal EF-hand motifs that account for its calcium-dependent activity.\",\n      \"method\": \"Protein purification from pig thyroid plasma membrane, microsequencing, cDNA cloning, domain analysis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — direct biochemical purification of the enzyme and identification of catalytic domains, replicated by subsequent cloning studies\",\n      \"pmids\": [\"10601291\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"DUOX2 (ThOX2) encodes a 1548-amino acid NADPH oxidase family member (theoretical MW 177 kDa, apparent 180 kDa) that accumulates at the apical membrane of thyrocytes co-localized with thyroperoxidase, and its mRNA expression is thyroid-specific and up-regulated by agents activating the cAMP pathway.\",\n      \"method\": \"Low-stringency cDNA library screening, Western blot, immunolocalization, Northern blot, chromosome mapping\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (cloning, Western blot, localization), replicated across two independent groups\",\n      \"pmids\": [\"10806195\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"DUOX2 (ThOX2) is a glycoprotein of ~180–190 kDa; deglycosylation reduces both ThOX1 and ThOX2 to ~160 kDa. The majority of ThOX protein accumulates intracellularly and only a small fraction reaches the cell surface. The intracellularly retained 'immature' form is enzymatically inactive. Ca2+ stimulates H2O2 generation in thyroid cells expressing ThOX. Co-expression with thyroperoxidase or p22(Phox) does not rescue surface expression or activity of ThOX in non-thyroid cells, indicating that additional thyroid-specific factors are required for full processing and enzymatic activity.\",\n      \"method\": \"Western blot, deglycosylation assay, H2O2 generation assay, transfection of non-thyroid cell lines, complementation assay in PLB-XCGD cells\",\n      \"journal\": \"Experimental cell research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Moderate — multiple orthogonal biochemical methods in one study with direct enzymatic readout and negative complementation controls\",\n      \"pmids\": [\"11822874\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"DUOX2 (LNOX2) protein is a ~164-kDa glycoprotein in human thyroid membrane fractions, with N-glycosylation accounting for at least 10–20 kDa of its apparent molecular mass. The protein is localized at the apical pole of thyrocytes and its mRNA is strongly and specifically expressed in thyroid tissue.\",\n      \"method\": \"Western blot with antipeptide antibodies, Northern blot across 23 tissues, immunostaining, quantitative PCR\",\n      \"journal\": \"The Journal of clinical endocrinology and metabolism\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple methods (Western blot, Northern blot, immunostaining) in a single lab\",\n      \"pmids\": [\"11443211\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"Biallelic (homozygous) nonsense mutations in DUOX2 (THOX2) result in complete loss of all functional protein domains and cause severe permanent congenital hypothyroidism with complete iodide-organification defect. Monoallelic (heterozygous) truncating mutations cause milder transient congenital hypothyroidism due to insufficient H2O2 production, establishing DUOX2 as the rate-limiting H2O2-generating enzyme for thyroid hormone synthesis.\",\n      \"method\": \"DNA sequencing of patients and relatives, mutational analysis of THOX1 and THOX2 genes, genotype-phenotype correlation\",\n      \"journal\": \"The New England journal of medicine\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — human genetic loss-of-function with clear dose-dependent phenotype replicated across multiple families and independently confirmed\",\n      \"pmids\": [\"12110737\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"The THOX2 gene spans 75 kb and is composed of 34 exons, arranged in a head-to-head configuration with THOX1 separated by a 16 kb intergenic region. Functional studies show that the THOX2 promoter drives transcriptional activity in differentiated thyroid cells but is not positively regulated by cAMP and is not restricted to thyroid cells in transfection assays.\",\n      \"method\": \"Genomic sequencing, exon mapping, promoter-reporter transfection assays in thyroid cell lines\",\n      \"journal\": \"Molecular and cellular endocrinology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct functional promoter assays combined with genomic structure determination in a single study\",\n      \"pmids\": [\"15062544\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"THOX2 and DUOXA2 genes are arranged in a head-to-head configuration sharing a bidirectional promoter region. The THOX2 transcription start is separated from DUOXA2 by only 170 bp. The intergenic region contains a TATA box and an Inr element and drives bidirectional promoter activity in thyroid PCCl3 cells, functionally linking DUOX2 expression to its maturation factor DUOXA2 at the transcriptional level.\",\n      \"method\": \"RLM-RACE (transcription start mapping), bidirectional reporter transfection assays in PCCl3 thyroid cells, gel shift assays\",\n      \"journal\": \"Molecular and cellular endocrinology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct functional promoter assays and transcription start mapping with multiple methods in a single lab\",\n      \"pmids\": [\"20060878\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"In the intestinal epithelium, DUOX2 and its maturation factor DUOXA2 are induced by C. albicans colonization in an IL-17 receptor-dependent manner; IL-17A addition to colonoids directly induces DUOX2/DUOXA2 and H2O2 production. Loss of intestinal DUOX2 function reduced C. albicans colonization at extended timepoints (>17 days) and increased the proportion of hyphal cells, while elevating IL-17A levels, revealing a feedback regulatory axis between IL-17 signaling and DUOX2-mediated H2O2 production that controls fungal filamentation and colonization.\",\n      \"method\": \"Expression profiling in germ-free mice colonized with C. albicans, IL-17 receptor knockout mice, colonoid IL-17A treatment with H2O2 measurement, intestinal DUOX2-knockout mouse colonization assay\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal in vivo and ex vivo methods in a single preprint study, not yet peer-reviewed\",\n      \"pmids\": [],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Social disruption stress upregulates Duox2 and Duoxa2 expression 2- to 8-fold in intestinal epithelial cells via β-adrenergic receptor signaling; this upregulation is reversed by β-AR blockade (propranolol) but not by α2-adrenergic, glucocorticoid receptor, or CRHR1 antagonism. NADPH oxidase inhibition with apocynin mitigated stress-induced ROS/RNS production and colitis severity, placing DUOX2 downstream of β-adrenergic signaling in stress-induced intestinal oxidative stress.\",\n      \"method\": \"Pharmacological antagonist pretreatment in SDR stress mouse model, IEC gene expression analysis, apocynin intervention in infectious and chemical colitis models\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single preprint, pharmacological (not genetic) dissection of pathway, indirect evidence for DUOX2 as β-adrenergic effector\",\n      \"pmids\": [],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"During neonatal colon development, functional sentinel goblet cell secretory responses are dependent on DUOX2 (a NADPH/Dual oxidase family member), as demonstrated by ex vivo analyses showing that DUOX2 loss impairs microbiota-dependent maturation of sentinel goblet cell function.\",\n      \"method\": \"In vivo and ex vivo analyses of pre- and post-weaning colonic goblet cell function in Duox2-deficient mice\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single preprint, phenotypic description of Duox2-deficient mice with limited mechanistic resolution in the abstract\",\n      \"pmids\": [],\n      \"is_preprint\": true\n    }\n  ],\n  \"current_model\": \"DUOX2 is a Ca2+-dependent, FAD- and NADPH-binding flavoprotein NADPH oxidase that localizes to the apical membrane of thyrocytes, where it generates H2O2 as the rate-limiting oxidant for thyroperoxidase-catalyzed iodide organification and thyroid hormone synthesis; its trafficking to the plasma membrane and enzymatic activation require additional thyroid-specific maturation factors (including DUOXA2, encoded by a co-regulated head-to-head promoter), and in the intestinal epithelium it is activated downstream of IL-17 and β-adrenergic signaling to produce reactive oxygen species that regulate microbial colonization and barrier function.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"DUOX2 is a Ca2+-dependent, FAD- and NADPH-binding flavoprotein NADPH oxidase that transfers electrons from NAD(P)H to molecular oxygen to generate H2O2, serving as the rate-limiting oxidant source for thyroid hormone synthesis [#0, #4]. The enzyme harbors FAD- and NADPH-binding consensus sequences and two N-terminal EF-hand motifs that confer calcium-dependent H2O2 production [#0]. In thyrocytes it accumulates at the apical membrane co-localized with thyroperoxidase, providing the H2O2 required for iodide organification, and its expression is thyroid-specific and up-regulated through the cAMP pathway [#1]. DUOX2 is a heavily N-glycosylated ~180–190 kDa protein whose immature, intracellularly retained form is enzymatically inactive; full surface expression and activity cannot be rescued by thyroperoxidase or p22(phox) alone, indicating a requirement for additional thyroid-specific maturation factors [#2]. This requirement is met by DUOXA2, whose gene lies in a head-to-head configuration with DUOX2 sharing a bidirectional promoter, functionally coupling the oxidase to its maturation factor at the transcriptional level [#6]. Biallelic nonsense mutations in DUOX2 cause severe permanent congenital hypothyroidism with complete iodide-organification defect, while heterozygous truncating mutations cause milder transient hypothyroidism, establishing DUOX2 as the dose-limiting H2O2-generating enzyme of thyroid hormone biogenesis [#4]. Beyond the thyroid, DUOX2 and DUOXA2 are induced in intestinal epithelium downstream of IL-17 receptor signaling, where DUOX2-derived H2O2 restrains Candida albicans filamentation and colonization in an IL-17 feedback axis [#7].\",\n  \"teleology\": [\n    {\n      \"year\": 1999,\n      \"claim\": \"Established the biochemical identity of DUOX2 as the catalytic flavoprotein of the thyroid Ca2+-dependent NAD(P)H oxidase, answering what enzyme generates thyroid H2O2.\",\n      \"evidence\": \"Protein purification from pig thyroid plasma membrane with microsequencing, cDNA cloning, and domain analysis\",\n      \"pmids\": [\"10601291\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not resolve the membrane topology or how electrons traverse the protein to oxygen\", \"Maturation/trafficking partners not identified\"]\n    },\n    {\n      \"year\": 2000,\n      \"claim\": \"Defined DUOX2 as a thyroid-specific apical-membrane oxidase co-localized with thyroperoxidase and regulated by cAMP, linking its expression to thyroid hormone synthesis.\",\n      \"evidence\": \"cDNA library screening, Western blot, immunolocalization, Northern blot, and chromosome mapping\",\n      \"pmids\": [\"10806195\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of apical targeting unresolved\", \"Functional coupling to thyroperoxidase shown by colocalization only\"]\n    },\n    {\n      \"year\": 2001,\n      \"claim\": \"Confirmed DUOX2 as a glycosylated apical thyroid membrane protein with strictly thyroid-restricted mRNA, reinforcing its tissue-specific role.\",\n      \"evidence\": \"Western blot with antipeptide antibodies, Northern blot across 23 tissues, immunostaining, qPCR\",\n      \"pmids\": [\"11443211\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab characterization\", \"Functional H2O2 readout not assessed\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Showed that the intracellular immature form is inactive and that surface expression requires thyroid-specific factors beyond thyroperoxidase or p22(phox), predicting a dedicated maturation factor.\",\n      \"evidence\": \"Deglycosylation assays, H2O2 generation assays, and complementation in non-thyroid and PLB-XCGD cells\",\n      \"pmids\": [\"11822874\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"The specific thyroid maturation factor not yet identified\", \"Step at which trafficking is blocked unresolved\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Demonstrated by human genetics that DUOX2 is the rate-limiting, dose-dependent H2O2 source for thyroid hormone synthesis, with biallelic loss causing permanent and monoallelic loss causing transient congenital hypothyroidism.\",\n      \"evidence\": \"DNA sequencing and genotype-phenotype correlation across patients and families\",\n      \"pmids\": [\"12110737\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Does not address modifier genes governing transient versus permanent phenotype\", \"Compensation by DUOX1 not fully delineated\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Determined genomic structure and promoter behavior, showing the DUOX2 promoter is active in differentiated thyroid cells but not directly cAMP-responsive or thyroid-restricted in transfection assays.\",\n      \"evidence\": \"Genomic sequencing, exon mapping, and promoter-reporter transfection in thyroid cell lines\",\n      \"pmids\": [\"15062544\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Reporter assays may not recapitulate native chromatin regulation\", \"Trans-acting factors driving thyroid specificity not identified\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Revealed that DUOX2 and its maturation factor DUOXA2 share a bidirectional promoter, providing a transcriptional mechanism for co-regulating oxidase and maturation factor expression.\",\n      \"evidence\": \"RLM-RACE transcription start mapping, bidirectional reporter assays in PCCl3 cells, and gel shift assays\",\n      \"pmids\": [\"20060878\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Specific transcription factors binding the bidirectional promoter not defined\", \"In vivo relevance of co-regulation not tested genetically\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Extended DUOX2 function to the intestinal epithelium, placing it downstream of IL-17 receptor signaling in an H2O2-mediated feedback axis that controls Candida albicans filamentation and colonization.\",\n      \"evidence\": \"Germ-free colonization, IL-17R knockout mice, colonoid IL-17A treatment with H2O2 measurement, and intestinal DUOX2-knockout colonization assays (preprint)\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Preprint, not yet peer-reviewed\", \"Direct molecular link between IL-17R signaling and DUOX2 induction not mapped\", \"Whether H2O2 acts directly on hyphae or via host cells unresolved\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Positioned DUOX2 as a candidate effector of β-adrenergic stress signaling driving intestinal oxidative stress and colitis severity.\",\n      \"evidence\": \"Pharmacological antagonist pretreatment in a social-disruption stress mouse model with apocynin intervention in colitis (preprint)\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Single preprint with pharmacological rather than genetic dissection\", \"Apocynin inhibits NADPH oxidases broadly, not DUOX2 specifically\", \"Direct β-AR-to-DUOX2 signaling link not established\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Implicated DUOX2 in microbiota-dependent maturation of neonatal sentinel goblet cell secretory function.\",\n      \"evidence\": \"In vivo and ex vivo analyses of colonic goblet cell function in Duox2-deficient mice (preprint)\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Single preprint with limited mechanistic resolution\", \"Molecular mediator linking DUOX2 H2O2 to goblet cell function not identified\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How DUOX2-derived H2O2 is spatially and temporally controlled across thyroid versus mucosal contexts, and the upstream signaling that gates its activity in the intestine, remain open.\",\n      \"evidence\": \"No direct experimental resolution in the available corpus\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Structural basis of electron transfer not determined\", \"Intestinal regulatory axes rest on preprint evidence only\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016491\", \"supporting_discovery_ids\": [0, 2]},\n      {\"term_id\": \"GO:0016174\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [0, 1, 3]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0006590\", \"supporting_discovery_ids\": [4]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"DUOXA2\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}