{"gene":"OXSR1","run_date":"2026-06-10T05:19:53","timeline":{"discoveries":[{"year":2026,"finding":"OXSR1 phosphorylates RhoB GTPase at threonine 37 upon intestinal injury, disrupting its interaction with ARHGAP17 and increasing GTP-bound RhoB levels, which leads to enhanced F-actin polymerization and YAP activation to promote intestinal regeneration. This positions OXSR1 as part of the osmolarity-sensing WNK-OXSR1 kinase cascade that mediates intestinal regeneration via Hippo-YAP signaling.","method":"Drosophila and mouse intestinal injury models, phosphoproteomics, co-immunoprecipitation, genetic loss-of-function, pharmacological inhibition, IBD patient samples","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (in vivo models in two organisms, phosphoproteomics, Co-IP, genetic and pharmacological perturbation) establishing substrate (RhoB T37), binding partner disruption (ARHGAP17), and downstream pathway (F-actin/YAP)","pmids":["41851502"],"is_preprint":false},{"year":2022,"finding":"OXSR1 inhibits NLRP3 inflammasome activation during mycobacterial infection by limiting potassium efflux. Genetic depletion or pharmacological inhibition of OXSR1 decreases intracellular potassium levels, triggering NLRP3 inflammasome activation, caspase-mediated IL-1β release, and downstream TNF-α activation, thereby reducing bacterial burden.","method":"Genetic depletion and pharmacological inhibition of OXSR1 in zebrafish embryos (M. marinum) and THP-1 cells (M. tuberculosis), measurement of intracellular potassium, inflammasome activation assays, cytokine quantification","journal":"Life science alliance","confidence":"High","confidence_rationale":"Tier 2 / Strong — two independent infection models (zebrafish and human cell line), genetic and pharmacological perturbation, multiple orthogonal readouts (potassium levels, caspase activity, IL-1β, TNF-α, bacterial burden)","pmids":["35545295"],"is_preprint":false},{"year":2025,"finding":"Deletion of OXSR1 in erythroid cells increases red blood cell density, and phosphoproteome analysis in OXSR1-depleted cells revealed dephosphorylation of the upstream kinase WNK1 and the downstream target KCC3 (SLC12A6), placing OXSR1 in the WNK1-OXSR1-KCC3 signaling axis controlling RBC hydration.","method":"Pooled CRISPR screens in erythroid cell line, density gradient selection, phosphoproteomics in OXSR1-depleted cells","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — CRISPR loss-of-function with phosphoproteomics provides mechanistic pathway placement, single preprint study","pmids":["bio_10.1101_2025.09.20.677403"],"is_preprint":true},{"year":2024,"finding":"OXSR1 is a downstream kinase of the WNK pathway that is activated in response to osmotic stress. The NRBP1 pseudokinase associates with WNK1 under osmotic stress and is required for activation of WNK1 and downstream OXSR1; OXSR1 contains a conserved CCT domain that participates in complex assembly with WNK and SPAK.","method":"Proximity ligation, co-immunoprecipitation, mass spectrometry, immunoblotting, knockdown/knockout of NRBP1, in vitro kinase activation assay with recombinant proteins, AlphaFold-3 structural modeling","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP, MS, in vitro reconstitution, and structural modeling in single preprint; places OXSR1 as downstream of WNK1/NRBP1 complex","pmids":["bio_10.1101_2024.12.12.628181"],"is_preprint":true},{"year":2024,"finding":"FTO (fat mass and obesity-associated protein) decreases OXSR1 expression through m6A modification of OXSR1 mRNA, as demonstrated by MeRIP and RIP assays, and overexpression of OXSR1 reverses the protective effects of FTO in LPS-induced kidney cell injury.","method":"MeRIP assay, RIP assay, Western blot, qRT-PCR, overexpression and knockdown experiments in HK2 cells and CLP mouse model","journal":"The Kaohsiung journal of medical sciences","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — MeRIP establishes m6A modification of OXSR1 by FTO with functional rescue, single lab single study","pmids":["39739936"],"is_preprint":false},{"year":2022,"finding":"OXSR1 is a direct target of miR-455-3p as validated by dual luciferase reporter assay; knockdown of OXSR1 attenuates copper-induced autophagy in hepatocytes, placing OXSR1 downstream of miR-455-3p in a pathway regulating autophagy under copper stress.","method":"Dual luciferase reporter assay, OXSR1 knockdown in broiler hepatocytes and cell lines, autophagy marker analysis (Beclin1, Atg5, LC3), in vivo copper exposure model","journal":"Chemico-biological interactions","confidence":"Low","confidence_rationale":"Tier 3 / Weak — luciferase reporter plus knockdown phenotype, single lab, limited mechanistic depth for OXSR1 specifically","pmids":["36372260"],"is_preprint":false}],"current_model":"OXSR1 is a serine/threonine kinase acting downstream of WNK family kinases in an osmosensing pathway that regulates ion homeostasis; it phosphorylates RhoB at T37 to promote F-actin polymerization and YAP-driven intestinal regeneration, limits potassium efflux to suppress NLRP3 inflammasome activation during mycobacterial infection, and controls red blood cell hydration through downstream phosphorylation of KCC3, with its mRNA subject to m6A modification by FTO."},"narrative":{"mechanistic_narrative":"OXSR1 is a serine/threonine kinase that operates as the effector arm of an osmosensing WNK kinase cascade, transducing osmotic and injury signals into ion-homeostatic and cytoskeletal responses [PMID:bio_10.1101_2024.12.12.628181]. Under osmotic stress, the NRBP1 pseudokinase associates with WNK1 and is required for activation of WNK1 and its downstream effector OXSR1, which engages WNK and SPAK through a conserved CCT domain that mediates complex assembly [PMID:bio_10.1101_2024.12.12.628181]. In the intestine, injury-activated OXSR1 phosphorylates RhoB GTPase at threonine 37, disrupting RhoB's interaction with ARHGAP17 and raising GTP-bound RhoB, thereby driving F-actin polymerization and YAP activation to promote regeneration [PMID:41851502]. The same WNK1-OXSR1 axis controls red blood cell hydration through phosphorylation of the downstream KCC3 (SLC12A6) transporter, with OXSR1 loss increasing RBC density [PMID:bio_10.1101_2025.09.20.677403]. OXSR1 also restrains innate immune signaling: by limiting potassium efflux it suppresses NLRP3 inflammasome activation, caspase-mediated IL-1β release, and TNF-α during mycobacterial infection [PMID:35545295]. OXSR1 expression is itself regulated post-transcriptionally, being reduced by FTO-mediated m6A modification of its mRNA [PMID:39739936].","teleology":[{"year":2022,"claim":"Established that OXSR1 functions as a brake on innate immune signaling by maintaining intracellular potassium, linking its kinase activity to inflammasome control rather than only ion transport.","evidence":"Genetic depletion and pharmacological inhibition in zebrafish (M. marinum) and THP-1 cells (M. tuberculosis) with potassium, caspase, IL-1β, TNF-α, and bacterial burden readouts","pmids":["35545295"],"confidence":"High","gaps":["Direct kinase substrate mediating potassium retention not identified","Whether the WNK upstream input governs this immune role untested"]},{"year":2024,"claim":"Defined the upstream activation logic of OXSR1, showing NRBP1 is required for osmotic-stress activation of WNK1 and downstream OXSR1 and that OXSR1's CCT domain mediates assembly into the WNK-SPAK complex.","evidence":"Proximity ligation, reciprocal Co-IP, mass spectrometry, NRBP1 knockdown/knockout, in vitro kinase activation with recombinant proteins, and AlphaFold-3 modeling (preprint)","pmids":["bio_10.1101_2024.12.12.628181"],"confidence":"Medium","gaps":["Single preprint not peer-reviewed","Physiological contexts requiring NRBP1-dependent activation undefined"]},{"year":2024,"claim":"Showed OXSR1 abundance is set post-transcriptionally, identifying FTO-mediated m6A modification of OXSR1 mRNA as a regulatory input in LPS-induced kidney injury.","evidence":"MeRIP and RIP assays, overexpression/knockdown rescue in HK2 cells and CLP mouse model","pmids":["39739936"],"confidence":"Medium","gaps":["m6A reader mediating OXSR1 mRNA fate not identified","Single study, kinase-pathway connection to the injury phenotype not dissected"]},{"year":2025,"claim":"Placed OXSR1 in a defined WNK1-OXSR1-KCC3 axis governing red blood cell hydration, connecting its kinase activity to a specific physiological transporter substrate.","evidence":"Pooled CRISPR screen with density-gradient selection and phosphoproteomics in OXSR1-depleted erythroid cells (preprint)","pmids":["bio_10.1101_2025.09.20.677403"],"confidence":"Medium","gaps":["Single preprint not peer-reviewed","Direct phosphorylation of KCC3 by OXSR1 not reconstituted in vitro"]},{"year":2026,"claim":"Identified RhoB T37 as a direct OXSR1 substrate and connected the WNK-OXSR1 cascade to Hippo-YAP-driven tissue regeneration, defining a cytoskeletal output of the kinase beyond ion transport.","evidence":"Drosophila and mouse intestinal injury models, phosphoproteomics, Co-IP, genetic and pharmacological perturbation, IBD patient samples","pmids":["41851502"],"confidence":"High","gaps":["How osmolarity sensing is transduced to OXSR1 in this context not resolved","Generality of RhoB phosphorylation across non-intestinal tissues unknown"]},{"year":null,"claim":"It remains unresolved how OXSR1 selects among its divergent outputs (KCC3-driven ion homeostasis, RhoB-driven cytoskeletal remodeling, potassium-dependent inflammasome control) in different cellular contexts.","evidence":"No single study integrates the substrate-selection logic across tissues","pmids":[],"confidence":"Low","gaps":["No unified model of context-dependent substrate choice","Spatial/temporal regulation of the WNK-OXSR1 complex not mapped"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[0,2]}],"localization":[],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0,3]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[1]}],"complexes":["WNK-OXSR1-SPAK complex"],"partners":["WNK1","NRBP1","SPAK","RHOB","ARHGAP17","KCC3"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"O95747","full_name":"Serine/threonine-protein kinase OSR1","aliases":["Oxidative stress-responsive 1 protein"],"length_aa":527,"mass_kda":58.0,"function":"Effector serine/threonine-protein kinase component of the WNK-SPAK/OSR1 kinase cascade, which is involved in various processes, such as ion transport, response to hypertonic stress and blood pressure (PubMed:16669787, PubMed:18270262, PubMed:21321328, PubMed:34289367). Specifically recognizes and binds proteins with a RFXV motif (PubMed:16669787, PubMed:17721439, PubMed:21321328). Acts downstream of WNK kinases (WNK1, WNK2, WNK3 or WNK4): following activation by WNK kinases, catalyzes phosphorylation of ion cotransporters, such as SLC12A1/NKCC2, SLC12A2/NKCC1, SLC12A3/NCC, SLC12A5/KCC2 or SLC12A6/KCC3, regulating their activity (PubMed:17721439). Mediates regulatory volume increase in response to hyperosmotic stress by catalyzing phosphorylation of ion cotransporters SLC12A1/NKCC2, SLC12A2/NKCC1 and SLC12A6/KCC3 downstream of WNK1 and WNK3 kinases (PubMed:16669787, PubMed:21321328). Phosphorylation of Na-K-Cl cotransporters SLC12A2/NKCC1 and SLC12A2/NKCC1 promote their activation and ion influx; simultaneously, phosphorylation of K-Cl cotransporters SLC12A5/KCC2 and SLC12A6/KCC3 inhibit their activity, blocking ion efflux (PubMed:16669787, PubMed:19665974, PubMed:21321328). Acts as a regulator of NaCl reabsorption in the distal nephron by mediating phosphorylation and activation of the thiazide-sensitive Na-Cl cotransporter SLC12A3/NCC in distal convoluted tubule cells of kidney downstream of WNK4 (PubMed:18270262). Also acts as a regulator of angiogenesis in endothelial cells downstream of WNK1 (PubMed:23386621, PubMed:25362046). Acts as an activator of inward rectifier potassium channels KCNJ2/Kir2.1 and KCNJ4/Kir2.3 downstream of WNK1: recognizes and binds the RXFXV/I variant motif on KCNJ2/Kir2.1 and KCNJ4/Kir2.3 and regulates their localization to the cell membrane without mediating their phosphorylation (PubMed:29581290). Phosphorylates RELL1, RELL2 and RELT (PubMed:16389068, PubMed:28688764). Phosphorylates PAK1 (PubMed:14707132). Phosphorylates PLSCR1 in the presence of RELT (PubMed:22052202)","subcellular_location":"Cytoplasm","url":"https://www.uniprot.org/uniprotkb/O95747/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/OXSR1","classification":"Not Classified","n_dependent_lines":29,"n_total_lines":1208,"dependency_fraction":0.024006622516556293},"opencell":{"profiled":true,"resolved_as":"","ensg_id":"ENSG00000172939","cell_line_id":"CID001229","localizations":[{"compartment":"cytoplasmic","grade":3},{"compartment":"nucleoplasm","grade":2}],"interactors":[{"gene":"WNK1","stoichiometry":10.0},{"gene":"WNK2","stoichiometry":0.2},{"gene":"WNK3","stoichiometry":0.2},{"gene":"RBM25","stoichiometry":0.2},{"gene":"DYNC1H1","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/target/CID001229","total_profiled":1310},"omim":[{"mim_id":"614495","title":"PSEUDOHYPOALDOSTERONISM, TYPE IID; PHA2D","url":"https://www.omim.org/entry/614495"},{"mim_id":"611213","title":"RELT-LIKE 2; RELL2","url":"https://www.omim.org/entry/611213"},{"mim_id":"611212","title":"RELT-LIKE 1; RELL1","url":"https://www.omim.org/entry/611212"},{"mim_id":"611211","title":"RECEPTOR EXPRESSED IN LYMPHOID TISSUES; RELT","url":"https://www.omim.org/entry/611211"},{"mim_id":"605775","title":"KELCH-LIKE 3; KLHL3","url":"https://www.omim.org/entry/605775"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Cytosol","reliability":"Supported"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/OXSR1"},"hgnc":{"alias_symbol":["KIAA1101"],"prev_symbol":["OSR1"]},"alphafold":{"accession":"O95747","domains":[{"cath_id":"3.30.200.20","chopping":"15-94","consensus_level":"medium","plddt":87.9622,"start":15,"end":94},{"cath_id":"1.10.510.10","chopping":"99-177_190-316","consensus_level":"high","plddt":89.5209,"start":99,"end":316},{"cath_id":"3.10.20.90","chopping":"435-527","consensus_level":"high","plddt":88.1548,"start":435,"end":527}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/O95747","model_url":"https://alphafold.ebi.ac.uk/files/AF-O95747-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-O95747-F1-predicted_aligned_error_v6.png","plddt_mean":76.56},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=OXSR1","jax_strain_url":"https://www.jax.org/strain/search?query=OXSR1"},"sequence":{"accession":"O95747","fasta_url":"https://rest.uniprot.org/uniprotkb/O95747.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/O95747/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/O95747"}},"corpus_meta":[{"pmid":"33468219","id":"PMC_33468219","title":"Knockdown of circ-FANCA alleviates LPS-induced HK2 cell injury via targeting miR-93-5p/OXSR1 axis in septic acute kidney injury.","date":"2021","source":"Diabetology & metabolic syndrome","url":"https://pubmed.ncbi.nlm.nih.gov/33468219","citation_count":51,"is_preprint":false},{"pmid":"31954517","id":"PMC_31954517","title":"MicroRNA-25-3p suppresses epileptiform discharges through inhibiting oxidative stress and apoptosis via targeting OXSR1 in neurons.","date":"2020","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/31954517","citation_count":24,"is_preprint":false},{"pmid":"35793478","id":"PMC_35793478","title":"Suppression of lncRNA GAS6-AS2 alleviates sepsis-related acute kidney injury through regulating the miR-136-5p/OXSR1 axis in vitro and in vivo.","date":"2022","source":"Renal failure","url":"https://pubmed.ncbi.nlm.nih.gov/35793478","citation_count":16,"is_preprint":false},{"pmid":"35751788","id":"PMC_35751788","title":"LncRNA ZFAS1 regulates the hippocampal neurons injury in epilepsy through the miR-15a-5p/OXSR1/NF-κB pathway.","date":"2022","source":"Metabolic brain disease","url":"https://pubmed.ncbi.nlm.nih.gov/35751788","citation_count":13,"is_preprint":false},{"pmid":"36372260","id":"PMC_36372260","title":"Long-term copper exposure caused hepatocytes autophagy in broiler via miR-455-3p-OXSR1 axis.","date":"2022","source":"Chemico-biological interactions","url":"https://pubmed.ncbi.nlm.nih.gov/36372260","citation_count":11,"is_preprint":false},{"pmid":"35545295","id":"PMC_35545295","title":"OXSR1 inhibits inflammasome activation by limiting potassium efflux during mycobacterial infection.","date":"2022","source":"Life science alliance","url":"https://pubmed.ncbi.nlm.nih.gov/35545295","citation_count":10,"is_preprint":false},{"pmid":"36609531","id":"PMC_36609531","title":"CircNRIP1 KNOCKDOWN ALLEVIATES LIPOPOLYSACCHARIDE-INDUCED HUMAN KIDNEY 2 CELL APOPTOSIS AND INFLAMMATION THROUGH miR-339-5p/OXSR1 PATHWAY.","date":"2023","source":"Shock (Augusta, Ga.)","url":"https://pubmed.ncbi.nlm.nih.gov/36609531","citation_count":9,"is_preprint":false},{"pmid":"35978931","id":"PMC_35978931","title":"Long non-coding RNA PVT1 regulates LPS-induced acute kidney injury in an in vitro model of HK-2 cells by modulating the miR-27a-3p/OXSR1 axis.","date":"2022","source":"Experimental and therapeutic medicine","url":"https://pubmed.ncbi.nlm.nih.gov/35978931","citation_count":9,"is_preprint":false},{"pmid":"39739936","id":"PMC_39739936","title":"Curcumin-induced exosomal FTO from bone marrow stem cells alleviates sepsis-associated acute kidney injury by modulating the m6A methylation of OXSR1.","date":"2024","source":"The Kaohsiung journal of medical sciences","url":"https://pubmed.ncbi.nlm.nih.gov/39739936","citation_count":8,"is_preprint":false},{"pmid":"34665488","id":"PMC_34665488","title":"LINC01291 promotes hepatocellular carcinoma development by targeting the miR-186-5p/OXSR1 axis.","date":"2021","source":"The journal of gene medicine","url":"https://pubmed.ncbi.nlm.nih.gov/34665488","citation_count":8,"is_preprint":false},{"pmid":"37549022","id":"PMC_37549022","title":"CIRC_0002131 CONTRIBUTES TO LPS-INDUCED APOPTOSIS, INFLAMMATION, AND OXIDATIVE INJURY IN HK-2 CELLS VIA INHIBITING THE BINDING BETWEEN MIR-942-5P AND OXSR1.","date":"2023","source":"Shock (Augusta, Ga.)","url":"https://pubmed.ncbi.nlm.nih.gov/37549022","citation_count":5,"is_preprint":false},{"pmid":"35385711","id":"PMC_35385711","title":"Silencing of long non-coding RNA ZFAS1 alleviates LPS-induced acute lung injury by mediating the miR-96-5p/OXSR1 axis in sepsis.","date":"2022","source":"The American journal of the medical sciences","url":"https://pubmed.ncbi.nlm.nih.gov/35385711","citation_count":5,"is_preprint":false},{"pmid":"34983467","id":"PMC_34983467","title":"Association of genetic variants of oxidative stress responsive kinase 1 (OXSR1) with asthma exacerbations in non-smoking asthmatics.","date":"2022","source":"BMC pulmonary medicine","url":"https://pubmed.ncbi.nlm.nih.gov/34983467","citation_count":5,"is_preprint":false},{"pmid":"37721476","id":"PMC_37721476","title":"circROCK1 Promotes septic myocardial injury through regulating miR-96-5p/OXSR1 axis.","date":"2023","source":"Acta biochimica Polonica","url":"https://pubmed.ncbi.nlm.nih.gov/37721476","citation_count":4,"is_preprint":false},{"pmid":"41851502","id":"PMC_41851502","title":"The WNK-OXSR1 osmosensing pathway mediates intestinal regeneration via Hippo-YAP signaling.","date":"2026","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/41851502","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.09.20.677403","title":"Pooled CRISPR screens identify genes and non-coding genomic regions that regulate red blood cell density","date":"2025-09-21","source":"bioRxiv","url":"https://doi.org/10.1101/2025.09.20.677403","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.12.12.628181","title":"NRBP1 pseudokinase binds to and activates the WNK pathway in response to osmotic stress","date":"2024-12-17","source":"bioRxiv","url":"https://doi.org/10.1101/2024.12.12.628181","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":12272,"output_tokens":1786,"usd":0.031803,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":8610,"output_tokens":2242,"usd":0.04955,"stage2_stop_reason":"end_turn"},"total_usd":0.081353,"stage1_batch_id":"msgbatch_013a8chtv3AWyTqv4z4sEF4C","stage2_batch_id":"msgbatch_01AHsuW63vinsvuTgzmQ3n62","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2026,\n      \"finding\": \"OXSR1 phosphorylates RhoB GTPase at threonine 37 upon intestinal injury, disrupting its interaction with ARHGAP17 and increasing GTP-bound RhoB levels, which leads to enhanced F-actin polymerization and YAP activation to promote intestinal regeneration. This positions OXSR1 as part of the osmolarity-sensing WNK-OXSR1 kinase cascade that mediates intestinal regeneration via Hippo-YAP signaling.\",\n      \"method\": \"Drosophila and mouse intestinal injury models, phosphoproteomics, co-immunoprecipitation, genetic loss-of-function, pharmacological inhibition, IBD patient samples\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (in vivo models in two organisms, phosphoproteomics, Co-IP, genetic and pharmacological perturbation) establishing substrate (RhoB T37), binding partner disruption (ARHGAP17), and downstream pathway (F-actin/YAP)\",\n      \"pmids\": [\"41851502\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"OXSR1 inhibits NLRP3 inflammasome activation during mycobacterial infection by limiting potassium efflux. Genetic depletion or pharmacological inhibition of OXSR1 decreases intracellular potassium levels, triggering NLRP3 inflammasome activation, caspase-mediated IL-1β release, and downstream TNF-α activation, thereby reducing bacterial burden.\",\n      \"method\": \"Genetic depletion and pharmacological inhibition of OXSR1 in zebrafish embryos (M. marinum) and THP-1 cells (M. tuberculosis), measurement of intracellular potassium, inflammasome activation assays, cytokine quantification\",\n      \"journal\": \"Life science alliance\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — two independent infection models (zebrafish and human cell line), genetic and pharmacological perturbation, multiple orthogonal readouts (potassium levels, caspase activity, IL-1β, TNF-α, bacterial burden)\",\n      \"pmids\": [\"35545295\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Deletion of OXSR1 in erythroid cells increases red blood cell density, and phosphoproteome analysis in OXSR1-depleted cells revealed dephosphorylation of the upstream kinase WNK1 and the downstream target KCC3 (SLC12A6), placing OXSR1 in the WNK1-OXSR1-KCC3 signaling axis controlling RBC hydration.\",\n      \"method\": \"Pooled CRISPR screens in erythroid cell line, density gradient selection, phosphoproteomics in OXSR1-depleted cells\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — CRISPR loss-of-function with phosphoproteomics provides mechanistic pathway placement, single preprint study\",\n      \"pmids\": [\"bio_10.1101_2025.09.20.677403\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"OXSR1 is a downstream kinase of the WNK pathway that is activated in response to osmotic stress. The NRBP1 pseudokinase associates with WNK1 under osmotic stress and is required for activation of WNK1 and downstream OXSR1; OXSR1 contains a conserved CCT domain that participates in complex assembly with WNK and SPAK.\",\n      \"method\": \"Proximity ligation, co-immunoprecipitation, mass spectrometry, immunoblotting, knockdown/knockout of NRBP1, in vitro kinase activation assay with recombinant proteins, AlphaFold-3 structural modeling\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP, MS, in vitro reconstitution, and structural modeling in single preprint; places OXSR1 as downstream of WNK1/NRBP1 complex\",\n      \"pmids\": [\"bio_10.1101_2024.12.12.628181\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"FTO (fat mass and obesity-associated protein) decreases OXSR1 expression through m6A modification of OXSR1 mRNA, as demonstrated by MeRIP and RIP assays, and overexpression of OXSR1 reverses the protective effects of FTO in LPS-induced kidney cell injury.\",\n      \"method\": \"MeRIP assay, RIP assay, Western blot, qRT-PCR, overexpression and knockdown experiments in HK2 cells and CLP mouse model\",\n      \"journal\": \"The Kaohsiung journal of medical sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — MeRIP establishes m6A modification of OXSR1 by FTO with functional rescue, single lab single study\",\n      \"pmids\": [\"39739936\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"OXSR1 is a direct target of miR-455-3p as validated by dual luciferase reporter assay; knockdown of OXSR1 attenuates copper-induced autophagy in hepatocytes, placing OXSR1 downstream of miR-455-3p in a pathway regulating autophagy under copper stress.\",\n      \"method\": \"Dual luciferase reporter assay, OXSR1 knockdown in broiler hepatocytes and cell lines, autophagy marker analysis (Beclin1, Atg5, LC3), in vivo copper exposure model\",\n      \"journal\": \"Chemico-biological interactions\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — luciferase reporter plus knockdown phenotype, single lab, limited mechanistic depth for OXSR1 specifically\",\n      \"pmids\": [\"36372260\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"OXSR1 is a serine/threonine kinase acting downstream of WNK family kinases in an osmosensing pathway that regulates ion homeostasis; it phosphorylates RhoB at T37 to promote F-actin polymerization and YAP-driven intestinal regeneration, limits potassium efflux to suppress NLRP3 inflammasome activation during mycobacterial infection, and controls red blood cell hydration through downstream phosphorylation of KCC3, with its mRNA subject to m6A modification by FTO.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"OXSR1 is a serine/threonine kinase that operates as the effector arm of an osmosensing WNK kinase cascade, transducing osmotic and injury signals into ion-homeostatic and cytoskeletal responses [#3]. Under osmotic stress, the NRBP1 pseudokinase associates with WNK1 and is required for activation of WNK1 and its downstream effector OXSR1, which engages WNK and SPAK through a conserved CCT domain that mediates complex assembly [#3]. In the intestine, injury-activated OXSR1 phosphorylates RhoB GTPase at threonine 37, disrupting RhoB's interaction with ARHGAP17 and raising GTP-bound RhoB, thereby driving F-actin polymerization and YAP activation to promote regeneration [#0]. The same WNK1-OXSR1 axis controls red blood cell hydration through phosphorylation of the downstream KCC3 (SLC12A6) transporter, with OXSR1 loss increasing RBC density [#2]. OXSR1 also restrains innate immune signaling: by limiting potassium efflux it suppresses NLRP3 inflammasome activation, caspase-mediated IL-1\\u03b2 release, and TNF-\\u03b1 during mycobacterial infection [#1]. OXSR1 expression is itself regulated post-transcriptionally, being reduced by FTO-mediated m6A modification of its mRNA [#4].\",\n  \"teleology\": [\n    {\n      \"year\": 2022,\n      \"claim\": \"Established that OXSR1 functions as a brake on innate immune signaling by maintaining intracellular potassium, linking its kinase activity to inflammasome control rather than only ion transport.\",\n      \"evidence\": \"Genetic depletion and pharmacological inhibition in zebrafish (M. marinum) and THP-1 cells (M. tuberculosis) with potassium, caspase, IL-1\\u03b2, TNF-\\u03b1, and bacterial burden readouts\",\n      \"pmids\": [\"35545295\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct kinase substrate mediating potassium retention not identified\", \"Whether the WNK upstream input governs this immune role untested\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Defined the upstream activation logic of OXSR1, showing NRBP1 is required for osmotic-stress activation of WNK1 and downstream OXSR1 and that OXSR1's CCT domain mediates assembly into the WNK-SPAK complex.\",\n      \"evidence\": \"Proximity ligation, reciprocal Co-IP, mass spectrometry, NRBP1 knockdown/knockout, in vitro kinase activation with recombinant proteins, and AlphaFold-3 modeling (preprint)\",\n      \"pmids\": [\"bio_10.1101_2024.12.12.628181\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single preprint not peer-reviewed\", \"Physiological contexts requiring NRBP1-dependent activation undefined\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Showed OXSR1 abundance is set post-transcriptionally, identifying FTO-mediated m6A modification of OXSR1 mRNA as a regulatory input in LPS-induced kidney injury.\",\n      \"evidence\": \"MeRIP and RIP assays, overexpression/knockdown rescue in HK2 cells and CLP mouse model\",\n      \"pmids\": [\"39739936\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"m6A reader mediating OXSR1 mRNA fate not identified\", \"Single study, kinase-pathway connection to the injury phenotype not dissected\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Placed OXSR1 in a defined WNK1-OXSR1-KCC3 axis governing red blood cell hydration, connecting its kinase activity to a specific physiological transporter substrate.\",\n      \"evidence\": \"Pooled CRISPR screen with density-gradient selection and phosphoproteomics in OXSR1-depleted erythroid cells (preprint)\",\n      \"pmids\": [\"bio_10.1101_2025.09.20.677403\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single preprint not peer-reviewed\", \"Direct phosphorylation of KCC3 by OXSR1 not reconstituted in vitro\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Identified RhoB T37 as a direct OXSR1 substrate and connected the WNK-OXSR1 cascade to Hippo-YAP-driven tissue regeneration, defining a cytoskeletal output of the kinase beyond ion transport.\",\n      \"evidence\": \"Drosophila and mouse intestinal injury models, phosphoproteomics, Co-IP, genetic and pharmacological perturbation, IBD patient samples\",\n      \"pmids\": [\"41851502\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How osmolarity sensing is transduced to OXSR1 in this context not resolved\", \"Generality of RhoB phosphorylation across non-intestinal tissues unknown\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"It remains unresolved how OXSR1 selects among its divergent outputs (KCC3-driven ion homeostasis, RhoB-driven cytoskeletal remodeling, potassium-dependent inflammasome control) in different cellular contexts.\",\n      \"evidence\": \"No single study integrates the substrate-selection logic across tissues\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No unified model of context-dependent substrate choice\", \"Spatial/temporal regulation of the WNK-OXSR1 complex not mapped\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [0, 2]}\n    ],\n    \"localization\": [],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 3]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [1]}\n    ],\n    \"complexes\": [\"WNK-OXSR1-SPAK complex\"],\n    \"partners\": [\"WNK1\", \"NRBP1\", \"SPAK\", \"RhoB\", \"ARHGAP17\", \"KCC3\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":3,"faith_total":3,"faith_pct":100.0}}