{"gene":"HTRA1","run_date":"2026-06-10T01:55:22","timeline":{"discoveries":[{"year":2004,"finding":"HtrA1 inhibits TGF-β family signaling by binding to a broad range of TGF-β family proteins (including BMP4, GDF5, TGFβs, and activin) via its protease domain and a linker region, preventing receptor activation; inhibition of TGFβ signaling is dependent on the proteolytic activity of HtrA1.","method":"GST-pulldown assay, deletion mutant analysis, cell-based signaling assay (C2C12 cells), chick embryo misexpression","journal":"Development","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal binding assay, domain deletion mutants, multiple TGFβ family members tested, in vivo phenotypic validation consistent with TGFβ inhibition","pmids":["14973287"],"is_preprint":false},{"year":2005,"finding":"HtrA1 directly degrades fragments of amyloid precursor protein (APP); an HtrA1 inhibitor causes accumulation of Aβ in astrocyte cell culture supernatants, and HtrA1 colocalizes with β-amyloid deposits in human brain samples.","method":"In vitro protease assay, cell culture supernatant analysis with HtrA1 inhibitor, immunofluorescence colocalization in human brain tissue","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vitro substrate degradation combined with inhibitor cell culture experiment and tissue colocalization, single lab","pmids":["15855271"],"is_preprint":false},{"year":2007,"finding":"HtrA1 inhibits mineral deposition by osteoblasts; both the protease domain and the PDZ domain are required for this inhibitory effect. HtrA1 cleaves extracellular matrix proteins decorin, fibronectin, and matrix Gla protein (MGP); cleavage of MGP requires both the protease and PDZ domains, whereas cleavage of decorin and fibronectin does not require the PDZ domain. Type I collagen is not cleaved.","method":"Overexpression and siRNA knockdown in 2T3 osteoblasts, recombinant HtrA1 domain mutant in vitro cleavage assays, mineralization assays","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro reconstitution with domain mutants, complementary overexpression and knockdown approaches, multiple substrates tested with defined domain requirements","pmids":["18156628"],"is_preprint":false},{"year":2009,"finding":"Human HtrA1 associates with microtubules in a PDZ domain-dependent and nocodazole-sensitive manner; it localizes to centrosomes and newly polymerized microtubules during assembly, promotes microtubule assembly in vitro, cosediments and copurifies with microtubules, and directly binds purified α- and β-tubulins. Downregulation of HtrA1 promotes cell motility while overexpression attenuates it.","method":"Immunofluorescence, microtubule co-sedimentation assay, co-purification, immunoprecipitation (endogenous HtrA1 pulling down α-, β-, γ-tubulin), in vitro microtubule assembly assay, cell motility assay with KD/OE","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — multiple orthogonal methods (co-sedimentation, co-purification, direct binding to purified tubulins, IP, in vitro assembly), PDZ domain dependence shown, functional readout","pmids":["19470753"],"is_preprint":false},{"year":2006,"finding":"HtrA1 expression is upregulated by cisplatin and paclitaxel treatment, resulting in limited autoproteolysis and activation of HtrA1. Active HtrA1 induces cell death in a serine protease-dependent manner and modulates chemotherapy-induced cytotoxicity.","method":"Forced expression and downregulation of HtrA1 in cancer cell lines, cytotoxicity assays, protease-inactive mutant comparison, Western blot for autoproteolysis","journal":"The Journal of clinical investigation","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — gain/loss-of-function with defined readout, protease-inactive mutant control establishing protease dependence, single lab","pmids":["16767218"],"is_preprint":false},{"year":2012,"finding":"Human HTRA1 degrades aggregated and fibrillar tau protein; neuronal cells with elevated HTRA1 accumulate less tau and neurofibrillary tangles; HTRA1 mRNA and activity are upregulated in response to elevated tau concentrations.","method":"In vitro degradation assay with aggregated/fibrillar tau, cell-based assay with HTRA1 overexpression, patient brain analysis, activity measurement","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 1-2 / Moderate — in vitro reconstitution with tau fibrils, cell-based validation, single lab","pmids":["22535953"],"is_preprint":false},{"year":2012,"finding":"Crystal structures and SAXS analysis of HtrA1 reveal a rare tandem of IGFBP- and Kazal-like modules in the N-terminal domain; the protease active site adopts a competent conformation in the absence of substrate or inhibitor, suggesting a two-state equilibrium/conformational selection model for substrate binding. The N-terminal IGFBP- and Kazal-like modules have no detectable effect on protease activity.","method":"X-ray crystallography, SAXS, enzymatic activity assays, binding studies with domain variants","journal":"Structure","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure combined with enzymatic assays and SAXS; multiple orthogonal methods in single rigorous study","pmids":["22578544"],"is_preprint":false},{"year":2010,"finding":"HtrA1 directly interacts with TSC2 (tuberin) but not TSC1 (hamartin); HtrA1 cleaves TSC2 both in vitro and in vivo, and alterations in HtrA1 expression cause changes in phosphorylation status of TSC2 downstream targets 4E-BP1 and S6K.","method":"Co-immunoprecipitation, colocalization, in vitro cleavage assay, in vivo cleavage assay, Western blot for downstream phosphorylation","journal":"Molecular cancer research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct binding and cleavage shown in vitro and in vivo, downstream pathway readout, single lab","pmids":["20671064"],"is_preprint":false},{"year":2013,"finding":"HtrA1 is induced by oxidative stress and promotes premature cell senescence through the p38 MAPK pathway in a protease activity-dependent manner; protease-inactive HtrA1 (S328A mutant) does not accelerate senescence, and HtrA1-induced senescence is abrogated by p38 MAPK inhibition.","method":"Transient transfection of wild-type vs. protease-inactive HtrA1, H2O2-induced senescence in MEFs and ARPE-19 cells, SA-β-galactosidase assay, p38 MAPK inhibitor, HtrA1-/- MEFs comparison","journal":"Experimental eye research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — protease-inactive mutant control establishes catalytic dependence, pathway inhibitor confirms p38 MAPK requirement, single lab","pmids":["23623979"],"is_preprint":false},{"year":2017,"finding":"HtrA1 activation is regulated by an allosteric inter-monomer communication mechanism within its trimer, independent of the PDZ domain. Inhibitor binding is precluded if HtrA1 monomers cannot communicate with each other. The HtrA1 trimer degrades complex extracellular fibrils including tubulin, amyloid beta, and tau.","method":"Biochemical allosteric assays, inhibitor binding studies with communication-defective mutants, in vitro fibril degradation assays","journal":"Scientific reports","confidence":"Medium","confidence_rationale":"Tier 1-2 / Moderate — mechanistic allosteric model with mutant validation, multiple substrates tested, single lab","pmids":["29093542"],"is_preprint":false},{"year":2018,"finding":"HTRA1 cleaves the Notch ligand JAG1 within its intracellular domain, leading to JAG1 protein degradation and enhancement of Delta/Notch signaling; HTRA1 physically interacts with JAG1. In HtrA1-deficient mice, endothelial Notch signaling is diminished and VEGF receptor-2 expression is increased in endothelial cells.","method":"Physical interaction assay, in vitro/in vivo cleavage of JAG1, siRNA knockdown and forced expression of HTRA1 in endothelial cells, constitutively active Notch1 rescue experiment, HtrA1-/- mouse analysis","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — direct substrate cleavage shown, physical interaction confirmed, epistasis via constitutively active Notch1 rescue, in vivo validation in knockout mice","pmids":["29713059"],"is_preprint":false},{"year":2018,"finding":"HTRA1 processes extracellular matrix proteins EFEMP1 and TSP1 (novel substrates), in addition to previously known substrates LTBP-1 and clusterin, in retinal pigment epithelium cells.","method":"Proteomic comparison of RPE cells with/without high-risk HTRA1 genotype, in vitro HTRA1 cleavage assays for novel substrates","journal":"Aging cell","confidence":"Medium","confidence_rationale":"Tier 1-2 / Moderate — in vitro cleavage assay for two novel substrates, supported by proteomics, single lab","pmids":["29730901"],"is_preprint":false},{"year":2018,"finding":"CADASIL brain vessels accumulate HTRA1 protein (4.9-fold enriched) co-localizing with Notch3ECD deposits, consistent with HTRA1 sequestration. Comparison with HTRA1 knockout mouse brain vessel proteome reveals 18 overlapping enriched proteins, several of which are confirmed as novel HTRA1 substrates by in vitro proteolysis assay, consistent with loss of HTRA1 function in CADASIL.","method":"Quantitative brain vessel proteomics, colocalization, HTRA1-/- mouse proteome comparison, in vitro proteolysis assay","journal":"Acta neuropathologica","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vitro substrate validation plus in vivo proteome comparison with knockout mice, single lab","pmids":["29725820"],"is_preprint":false},{"year":2019,"finding":"Loss of HTRA1 in vascular smooth muscle cells (VSMCs) increases JAG1 protein levels and NOTCH3 signaling activity, and also enhances TGFβ-SMAD2/3 signaling. Combined over-activation of NOTCH3 and TGFβ pathways leads to additive accumulation of HES/HEY transcriptional repressors, repressing contractile VSMC marker genes and resulting in an immature VSMC phenotype with impaired arterial vasoconstriction in Htra1-deficient mice.","method":"HtrA1-/- mouse analysis, VSMC differentiation assays, Notch3 and TGFβ pathway activation/inhibition, ex vivo vasoconstriction assay","journal":"Scientific reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo knockout mouse with defined phenotype, pathway epistasis via pathway activation experiments, functional vasoconstriction readout, single lab","pmids":["31796853"],"is_preprint":false},{"year":2017,"finding":"HTRA1 inhibits canonical Wnt/β-catenin signaling in both paracrine and autocrine manners; HTRA1 forms a complex with β-catenin and reduces the proliferation rates of cells, affecting expression of several Wnt target genes.","method":"Luciferase reporter assay for Wnt activity, co-immunoprecipitation of HTRA1 and β-catenin, cell proliferation assay, overexpression and knockdown","journal":"Scientific reports","confidence":"Medium","confidence_rationale":"Tier 2-3 / Moderate — co-IP showing complex formation, Wnt reporter assay, functional proliferation readout, single lab","pmids":["29269789"],"is_preprint":false},{"year":2014,"finding":"HtrA1 plays important roles in trophoblast differentiation from Tpbpa-positive precursors in the ectoplacental cone. HtrA1-/- mice show intrauterine growth retardation with reduced junctional zone size, aberrant labyrinth vascularization, decreased spongiotrophoblasts and glycogen trophoblasts, and impaired maternal artery remodeling.","method":"HtrA1-/- mouse knockout analysis, histology, immunostaining for trophoblast markers, vascular morphometry","journal":"Developmental biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic knockout with defined cellular and vascular phenotypes, in vivo, single lab","pmids":["25446274"],"is_preprint":false},{"year":2012,"finding":"MiR-30e and miR-181d are posttranscriptional negative regulators of HtrA1 by binding to its 3' UTR; overexpression of HtrA1 in the developing forebrain recapitulates aspects of the Dicer-/- phenotype affecting radial glia proliferation, and in vivo overexpression of miR-30e and miR-181d in Dicer-/- forebrain rescues RG proliferation defects.","method":"3'UTR luciferase reporter assay, in vivo rescue experiment in Dicer-/- mice, forebrain overexpression of HtrA1","journal":"Cell death & disease","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — 3'UTR binding validated by reporter assay, in vivo rescue experiment, single lab","pmids":["22854828"],"is_preprint":false},{"year":2016,"finding":"HTRA1 is epigenetically silenced in HCT116 colon carcinoma cells via the epigenetic adaptor protein MBD2; depletion of HTRA1 causes centrosome amplification and polyploidy in SW480 cells and primary MEFs.","method":"MBD2 knockdown/chromatin analysis, HTRA1 depletion by siRNA, centrosome counting, ploidy analysis","journal":"BMC cancer","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — epigenetic mechanism identified via MBD2, loss-of-function with cellular phenotype, single lab","pmids":["27388476"],"is_preprint":false},{"year":2014,"finding":"IFN-γ negatively controls HTRA1 expression through activation of the p38 MAPK/STAT1 pathway; STAT1 directly binds the HTRA1 promoter after IFN-γ stimulation. Neutralization of HTRA1 reversed enhanced collagen-induced arthritis (CIA) frequency and severity in IFN-γ-deficient mice.","method":"Dual luciferase reporter assay, chromatin immunoprecipitation (ChIP), p38 MAPK pathway inhibition, IFN-γ-/- mouse model of CIA, anti-HTRA1 antibody neutralization","journal":"Journal of immunology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP demonstrates direct STAT1 promoter binding, in vivo neutralization rescue, single lab with multiple methods","pmids":["24907345"],"is_preprint":false},{"year":2015,"finding":"The trimeric HtrA1 catalytic domain forms a cage-like inhibition complex with antibody 94 (IgG94): one Fab binds peripherally to each protomer via loops B and C of the catalytic domain, suggesting an allosteric inhibition mechanism. The IgG94 complex (636 kDa) consists of three centrally located IgG molecules coordinating two HtrA1_Cat trimers with all six active sites pointing inward.","method":"Negative-staining EM, biochemical complex characterization, epitope mapping, enzymatic activity assays","journal":"The Biochemical journal","confidence":"Medium","confidence_rationale":"Tier 1-2 / Moderate — EM structural characterization plus epitope mapping and activity assays, single lab","pmids":["26385991"],"is_preprint":false},{"year":2018,"finding":"HTRA1 is identified as a novel podocyte antigen in a subset of patients with primary membranous nephropathy; anti-HTRA1 autoantibodies are predominantly IgG4, and HTRA1 is specifically detected within immune deposits in affected kidney tissue.","method":"Immunoblotting of glomerular proteins, differential immunoprecipitation, mass spectrometry, laser-capture microdissection, protein fragment microarray, biopsy immunostaining","journal":"Journal of the American Society of Nephrology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple converging antigen identification methods, tissue immunostaining in 14 patients, single study","pmids":["33952630"],"is_preprint":false},{"year":2024,"finding":"HTRA1 inhibits aggregation of α-synuclein, FUS, and TDP-43; disaggregates preformed α-syn fibrils and converts them into non-seeding, non-toxic species; reduces endogenous α-syn seeding when HTRA1 is knocked down; targets the NAC domain of α-syn; and detoxifies α-syn fibrils in primary neurons. The protease domain is necessary and sufficient for inhibiting aggregation, but this activity is proteolytically independent.","method":"In vitro aggregation inhibition assay, fibril disaggregation assay, seeding assay, HTRA1 knockdown cell assay, domain deletion mutants, primary neuron toxicity assay","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro reconstitution with multiple aggregating proteins, domain dissection establishing protease-domain sufficiency and proteolysis independence, cell-based seeding assay, primary neuron validation","pmids":["38499535"],"is_preprint":false},{"year":2008,"finding":"Processed forms of HtrA1 are found intracellularly and intranuclearly; the active intranuclear form has an apparent molecular weight of ~29 kDa. HtrA1 is found associated with HPV E6 and E7 proteins, and HPV E6/E7 expression is associated with post-transcriptional upregulation of HtrA1 (notably the nuclear form).","method":"Cellular fractionation, immunoblotting for HtrA1 isoforms, co-immunoprecipitation with HPV E6/E7","journal":"Journal of cellular biochemistry","confidence":"Low","confidence_rationale":"Tier 3 / Weak — fractionation and single Co-IP, limited mechanistic follow-up, single lab","pmids":["18452160"],"is_preprint":false},{"year":2020,"finding":"RUNX2 co-operates with EGR1 to co-repress Htra1 expression; RUNX2 binds to Htra1 enhancers (seven validated by dual-luciferase assay), and Re-ChIP assays confirm co-occupancy of RUNX2 and EGR1 at these sites. Co-repression of Htra1 by RUNX2/EGR1 is associated with increased expression of osteoblast differentiation markers.","method":"ChIP-seq, dual-luciferase enhancer assays, Re-ChIP, RNA-seq, siRNA knockdown","journal":"Journal of cellular physiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP-seq plus Re-ChIP confirms co-occupancy, multiple enhancers validated by reporter assay, single lab","pmids":["32324256"],"is_preprint":false},{"year":2024,"finding":"HTRA1 interacts with SLC7A11 (xCT) through its Kazal structural domain and upregulates SLC7A11 expression, thereby inhibiting ferroptosis and contributing to chemoresistance to 5-FU/L-OHP in colorectal cancer cells.","method":"Co-immunoprecipitation, domain mapping (Kazal domain), gain/loss-of-function, ROS and MDA measurement, electron microscopy for mitochondria, cell viability assays","journal":"Cell death discovery","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single Co-IP with domain mapping, single lab, no in vitro reconstitution of direct binding","pmids":["38740771"],"is_preprint":false},{"year":2018,"finding":"HtrA1 regulates astrocyte differentiation and injury response: genetic deletion of HtrA1 during gliogenesis accelerates astrocyte differentiation, and HtrA1-ablated astrocytes show altered chondroitin sulfate proteoglycan expression, inhibition of neurite extension, and elevated TGF-β family proteins. Brain injury induces HtrA1 in reactive astrocytes and loss of HtrA1 impairs wound closure.","method":"HtrA1 genetic deletion in mice, astrocyte culture with HtrA1 ablation, neurite extension assay, injury response assay, immunostaining","journal":"The Journal of neuroscience","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo genetic deletion with defined cellular phenotypes and TGFβ pathway link, single lab","pmids":["29483282"],"is_preprint":false}],"current_model":"HTRA1 is a homotrimeric serine protease that is activated by an allosteric inter-monomer communication mechanism and whose PDZ domain regulates substrate access; it cleaves a broad range of extracellular substrates (TGF-β family ligands, APP fragments, ECM proteins including decorin, fibronectin, MGP, EFEMP1, TSP1, LTBP-1) to modulate TGF-β/BMP, Notch/JAG1, and Wnt/β-catenin signaling, and intracellularly degrades aggregated tau and α-synuclein fibrils in a proteolysis-independent disaggregation mode, while also associating with microtubules via its PDZ domain to regulate cell motility."},"narrative":{"mechanistic_narrative":"HTRA1 is a homotrimeric, secreted serine protease that regulates extracellular signaling and matrix homeostasis by proteolytically processing a broad set of substrates, and that secondarily moonlights as a chaperone-like disaggregase and microtubule-associated protein [PMID:14973287, PMID:18156628, PMID:38499535, PMID:19470753]. Its protease domain binds and antagonizes TGF-β family ligands (BMP4, GDF5, TGFβs, activin) in a proteolysis-dependent manner to block receptor activation [PMID:14973287], and it cleaves extracellular matrix and matricellular substrates including decorin, fibronectin, matrix Gla protein, EFEMP1, TSP1, and LTBP-1, with substrate-specific dependence on its regulatory PDZ domain [PMID:18156628, PMID:29730901]. Through cleavage of the Notch ligand JAG1 within its intracellular domain, HTRA1 promotes JAG1 degradation and tunes Notch3 signaling, and loss of HTRA1 in vascular smooth muscle cells de-represses both JAG1/NOTCH3 and TGFβ-SMAD2/3 signaling, driving HES/HEY-mediated repression of contractile genes and impaired vasoconstriction [PMID:29713059, PMID:31796853]; HTRA1 also restrains canonical Wnt/β-catenin signaling and forms a complex with β-catenin [PMID:29269789]. Catalytically, HTRA1 adopts an active-competent conformation even without substrate, and trimer activation proceeds through allosteric inter-monomer communication independent of the PDZ domain [PMID:22578544, PMID:29093542]. Beyond proteolysis, HTRA1 disaggregates amyloidogenic protein fibrils—degrading aggregated tau and, via its protease domain in a proteolysis-independent mode, disaggregating α-synuclein, FUS, and TDP-43 into non-seeding, non-toxic species [PMID:22535953, PMID:38499535]—and associates with microtubules and tubulin via its PDZ domain to limit cell motility [PMID:19470753]. HTRA1 is induced by cellular stress and chemotherapeutics to drive protease-dependent cell death and p38 MAPK-dependent senescence [PMID:16767218, PMID:23623979], and is essential in vivo for trophoblast differentiation and placental vascular remodeling [PMID:25446274].","teleology":[{"year":2004,"claim":"Established HTRA1 as a negative regulator of TGF-β family signaling, defining its first signaling role and showing this depends on its protease activity.","evidence":"GST-pulldown, domain deletion mutants, and C2C12 signaling assays with chick embryo misexpression","pmids":["14973287"],"confidence":"High","gaps":["Whether inhibition reflects ligand cleavage versus stoichiometric sequestration not fully resolved","Physiological substrates among the tested ligands not pinpointed"]},{"year":2005,"claim":"Linked HTRA1 proteolysis to amyloid biology by showing it degrades APP fragments and colocalizes with β-amyloid deposits.","evidence":"In vitro protease assay, astrocyte supernatant analysis with HtrA1 inhibitor, human brain immunofluorescence","pmids":["15855271"],"confidence":"Medium","gaps":["Cleavage sites and physiological relevance to Aβ clearance not defined","Single lab"]},{"year":2007,"claim":"Defined HTRA1 as an ECM-processing protease and dissected differential PDZ-domain requirements across substrates, linking it to mineralization control.","evidence":"Osteoblast overexpression/knockdown plus recombinant domain-mutant in vitro cleavage of decorin, fibronectin, and MGP","pmids":["18156628"],"confidence":"High","gaps":["Mechanistic basis for PDZ-dependence of MGP versus PDZ-independence of decorin/fibronectin unclear","Cleavage product fate in vivo not tracked"]},{"year":2009,"claim":"Revealed a non-proteolytic cytoskeletal role: HTRA1 binds tubulin via its PDZ domain, promotes microtubule assembly, and suppresses cell motility.","evidence":"Co-sedimentation, co-purification, direct tubulin binding, IP, in vitro assembly, and KD/OE motility assays","pmids":["19470753"],"confidence":"High","gaps":["Relationship between cytoplasmic microtubule role and secreted protease function unresolved","Whether protease activity acts on microtubule-associated substrates unknown"]},{"year":2006,"claim":"Connected HTRA1 to stress-induced cell fate, showing chemotherapeutics trigger its autoproteolytic activation and protease-dependent cell death.","evidence":"Gain/loss-of-function in cancer cells with protease-inactive mutant control and autoproteolysis Western blots","pmids":["16767218"],"confidence":"Medium","gaps":["Intracellular substrates mediating death not identified","Single lab"]},{"year":2010,"claim":"Implicated HTRA1 in mTOR pathway control via direct binding and cleavage of TSC2.","evidence":"Co-IP, in vitro/in vivo cleavage, and downstream 4E-BP1/S6K phosphorylation readouts","pmids":["20671064"],"confidence":"Medium","gaps":["How a secreted protease accesses cytoplasmic TSC2 not reconciled","Single lab"]},{"year":2012,"claim":"Defined the structural basis of HTRA1 catalysis, showing the active site is competent without substrate, supporting a conformational-selection model.","evidence":"X-ray crystallography, SAXS, and enzymatic assays with domain variants","pmids":["22578544"],"confidence":"High","gaps":["Functional role of the IGFBP-/Kazal tandem module not established","Full-length trimer architecture not solved"]},{"year":2012,"claim":"Extended HTRA1 into tauopathy by showing it degrades aggregated/fibrillar tau and is upregulated by elevated tau.","evidence":"In vitro fibrillar-tau degradation, HTRA1-overexpressing neuronal cells, patient brain analysis","pmids":["22535953"],"confidence":"Medium","gaps":["Mechanism of accessing intracellular tau unclear","Single lab"]},{"year":2013,"claim":"Linked HTRA1 to oxidative-stress-induced senescence through protease-dependent p38 MAPK activation.","evidence":"WT vs S328A protease-inactive HtrA1 in H2O2-treated MEFs/ARPE-19 with p38 inhibitor and HtrA1-/- comparison","pmids":["23623979"],"confidence":"Medium","gaps":["Substrate upstream of p38 not identified","Single lab"]},{"year":2017,"claim":"Established the trimer activation mechanism: allosteric inter-monomer communication, PDZ-independent, gates catalysis and fibril degradation.","evidence":"Allosteric assays, inhibitor binding with communication-defective mutants, fibril degradation assays","pmids":["29093542"],"confidence":"Medium","gaps":["Structural residues mediating communication not fully mapped","Single lab"]},{"year":2017,"claim":"Identified HTRA1 as an inhibitor of canonical Wnt/β-catenin signaling acting both autocrine and paracrine.","evidence":"Wnt luciferase reporter, HTRA1–β-catenin co-IP, proliferation assays with OE/KD","pmids":["29269789"],"confidence":"Medium","gaps":["Whether β-catenin is a cleavage substrate or binding partner only is unclear","Single co-IP without reciprocal validation"]},{"year":2018,"claim":"Defined the JAG1/Notch axis: HTRA1 cleaves JAG1 to enhance Delta/Notch signaling and regulate endothelial VEGFR2, establishing a vascular signaling function.","evidence":"Physical interaction, in vitro/in vivo JAG1 cleavage, endothelial KD/OE, constitutively active Notch1 rescue, HtrA1-/- mice","pmids":["29713059"],"confidence":"High","gaps":["JAG1 cleavage site within intracellular domain not mapped","Topological basis for intracellular cleavage by a secreted protease unresolved"]},{"year":2018,"claim":"Expanded the secreted-substrate repertoire to EFEMP1 and TSP1 in retinal pigment epithelium, linking genotype to altered ECM processing.","evidence":"RPE proteomics by HTRA1 genotype plus in vitro cleavage of novel substrates","pmids":["29730901"],"confidence":"Medium","gaps":["Functional consequences of EFEMP1/TSP1 cleavage in vivo not established","Single lab"]},{"year":2018,"claim":"Connected HTRA1 to cerebral small-vessel disease, showing HTRA1 sequestration on Notch3ECD deposits in CADASIL and loss-of-function substrate accumulation.","evidence":"Quantitative brain vessel proteomics, colocalization, HTRA1-/- proteome comparison, in vitro proteolysis","pmids":["29725820"],"confidence":"Medium","gaps":["Causal contribution of sequestration to disease progression not proven","Single lab"]},{"year":2019,"claim":"Integrated HTRA1's JAG1/NOTCH3 and TGFβ functions into a vascular phenotype, explaining how its loss drives immature VSMCs and impaired vasoconstriction.","evidence":"HtrA1-/- mice, VSMC differentiation, Notch3/TGFβ pathway manipulation, ex vivo vasoconstriction","pmids":["31796853"],"confidence":"Medium","gaps":["Relative contribution of the two pathways not quantified","Single lab"]},{"year":2024,"claim":"Defined a proteolysis-independent disaggregase activity: the HTRA1 protease domain alone inhibits and reverses α-synuclein, FUS, and TDP-43 aggregation into non-toxic species.","evidence":"In vitro aggregation/disaggregation/seeding assays, domain deletions, HTRA1 KD, primary neuron toxicity","pmids":["38499535"],"confidence":"High","gaps":["Structural basis for proteolysis-independent NAC-domain targeting unresolved","In vivo neuroprotective relevance not established"]},{"year":null,"claim":"How HTRA1's multiple compartmental activities—secreted ECM/ligand proteolysis, cytoplasmic/intracellular substrate cleavage, microtubule binding, and proteolysis-independent disaggregation—are coordinated within a single protein remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unified model reconciling extracellular and intracellular pools","Mechanism switching between proteolytic and disaggregase modes unknown","Spatial regulation of substrate selection undefined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[0,2,7,10,11]},{"term_id":"GO:0016787","term_label":"hydrolase activity","supporting_discovery_ids":[2,5,10,11]},{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[3]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[0,21]}],"localization":[{"term_id":"GO:0005576","term_label":"extracellular region","supporting_discovery_ids":[0,2,11]},{"term_id":"GO:0005856","term_label":"cytoskeleton","supporting_discovery_ids":[3]},{"term_id":"GO:0005815","term_label":"microtubule organizing center","supporting_discovery_ids":[3]},{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[22]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0,10,13,14]},{"term_id":"R-HSA-1474244","term_label":"Extracellular matrix organization","supporting_discovery_ids":[2,11]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[13,15,25]},{"term_id":"R-HSA-8953897","term_label":"Cellular responses to stimuli","supporting_discovery_ids":[4,8]}],"complexes":[],"partners":["JAG1","TSC2","CTNNB1","TUBA","TUBB","SLC7A11"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q92743","full_name":"Serine protease HTRA1","aliases":["High-temperature requirement A serine peptidase 1","L56","Serine protease 11"],"length_aa":480,"mass_kda":51.3,"function":"Serine protease with a variety of targets, including extracellular matrix proteins such as fibronectin. HTRA1-generated fibronectin fragments further induce synovial cells to up-regulate MMP1 and MMP3 production. May also degrade proteoglycans, such as aggrecan, decorin and fibromodulin. Through cleavage of proteoglycans, may release soluble FGF-glycosaminoglycan complexes that promote the range and intensity of FGF signals in the extracellular space. Regulates the availability of insulin-like growth factors (IGFs) by cleaving IGF-binding proteins. Inhibits signaling mediated by TGF-beta family members. This activity requires the integrity of the catalytic site, although it is unclear whether TGF-beta proteins are themselves degraded. By acting on TGF-beta signaling, may regulate many physiological processes, including retinal angiogenesis and neuronal survival and maturation during development. 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sciences","url":"https://pubmed.ncbi.nlm.nih.gov/34639128","citation_count":21,"is_preprint":false},{"pmid":"31796853","id":"PMC_31796853","title":"Loss of the serine protease HTRA1 impairs smooth muscle cells maturation.","date":"2019","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/31796853","citation_count":20,"is_preprint":false},{"pmid":"34270682","id":"PMC_34270682","title":"Heterozygous HTRA1 nonsense or frameshift mutations are pathogenic.","date":"2021","source":"Brain : a journal of neurology","url":"https://pubmed.ncbi.nlm.nih.gov/34270682","citation_count":19,"is_preprint":false},{"pmid":"25776486","id":"PMC_25776486","title":"HtrA1 resensitizes multidrug-resistant hepatocellular carcinoma cells by targeting XIAP.","date":"2015","source":"Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie","url":"https://pubmed.ncbi.nlm.nih.gov/25776486","citation_count":19,"is_preprint":false},{"pmid":"33277762","id":"PMC_33277762","title":"Importance of two PDZ domains for the proteolytic and chaperone activities of Helicobacter pylori serine protease HtrA.","date":"2020","source":"Cellular microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/33277762","citation_count":18,"is_preprint":false},{"pmid":"34976310","id":"PMC_34976310","title":"Function, molecular mechanisms, and therapeutic potential of bacterial HtrA proteins: An evolving view.","date":"2021","source":"Computational and structural biotechnology journal","url":"https://pubmed.ncbi.nlm.nih.gov/34976310","citation_count":17,"is_preprint":false},{"pmid":"32324256","id":"PMC_32324256","title":"RUNX2 co-operates with EGR1 to regulate osteogenic differentiation through Htra1 enhancers.","date":"2020","source":"Journal of cellular physiology","url":"https://pubmed.ncbi.nlm.nih.gov/32324256","citation_count":17,"is_preprint":false},{"pmid":"37183214","id":"PMC_37183214","title":"Trimer stability of Helicobacter pylori HtrA is regulated by a natural mutation in the protease domain.","date":"2023","source":"Medical microbiology and immunology","url":"https://pubmed.ncbi.nlm.nih.gov/37183214","citation_count":17,"is_preprint":false},{"pmid":"37232715","id":"PMC_37232715","title":"HTRA1 in Placental Cell Models: A Possible Role in Preeclampsia.","date":"2023","source":"Current issues in molecular biology","url":"https://pubmed.ncbi.nlm.nih.gov/37232715","citation_count":16,"is_preprint":false},{"pmid":"26385991","id":"PMC_26385991","title":"The trimeric serine protease HtrA1 forms a cage-like inhibition complex with an anti-HtrA1 antibody.","date":"2015","source":"The Biochemical journal","url":"https://pubmed.ncbi.nlm.nih.gov/26385991","citation_count":16,"is_preprint":false},{"pmid":"30795802","id":"PMC_30795802","title":"Association of HTRA1 and ARMS2 gene polymorphisms with response to intravitreal ranibizumab among neovascular age-related macular degenerative subjects.","date":"2019","source":"Human genomics","url":"https://pubmed.ncbi.nlm.nih.gov/30795802","citation_count":16,"is_preprint":false},{"pmid":"29561953","id":"PMC_29561953","title":"Heterozygous HTRA1 missense mutation in CADASIL-like family disease.","date":"2018","source":"Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas","url":"https://pubmed.ncbi.nlm.nih.gov/29561953","citation_count":15,"is_preprint":false},{"pmid":"17292962","id":"PMC_17292962","title":"HtrA1 is a novel mast cell serine protease of mice and men.","date":"2007","source":"Molecular immunology","url":"https://pubmed.ncbi.nlm.nih.gov/17292962","citation_count":15,"is_preprint":false},{"pmid":"38740771","id":"PMC_38740771","title":"HTRA1 interacts with SLC7A11 to modulate colorectal cancer chemosensitivity by inhibiting ferroptosis.","date":"2024","source":"Cell death discovery","url":"https://pubmed.ncbi.nlm.nih.gov/38740771","citation_count":14,"is_preprint":false},{"pmid":"29409460","id":"PMC_29409460","title":"HtrA1 as a promising tissue marker in cancer: a meta-analysis.","date":"2018","source":"BMC cancer","url":"https://pubmed.ncbi.nlm.nih.gov/29409460","citation_count":14,"is_preprint":false},{"pmid":"24493577","id":"PMC_24493577","title":"Expression and localization of serine protease Htra1 in neuroblastoma: correlation with cellular differentiation grade.","date":"2014","source":"Journal of neuro-oncology","url":"https://pubmed.ncbi.nlm.nih.gov/24493577","citation_count":14,"is_preprint":false},{"pmid":"26403966","id":"PMC_26403966","title":"HtrA1 regulates epithelial-mesenchymal transition in hepatocellular carcinoma.","date":"2015","source":"Biochemical and biophysical research 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Immunosuppression?","date":"2022","source":"Frontiers in immunology","url":"https://pubmed.ncbi.nlm.nih.gov/35371018","citation_count":14,"is_preprint":false},{"pmid":"28739676","id":"PMC_28739676","title":"SHAPE analysis of the htrA RNA thermometer from Salmonella enterica.","date":"2017","source":"RNA (New York, N.Y.)","url":"https://pubmed.ncbi.nlm.nih.gov/28739676","citation_count":13,"is_preprint":false},{"pmid":"25761858","id":"PMC_25761858","title":"Serine protease HtrA1 as an inhibitor on proliferation invasion and migration of gastric cancer.","date":"2015","source":"Medical oncology (Northwood, London, England)","url":"https://pubmed.ncbi.nlm.nih.gov/25761858","citation_count":13,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":46544,"output_tokens":6531,"usd":0.118799,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":15477,"output_tokens":4872,"usd":0.099593,"stage2_stop_reason":"end_turn"},"total_usd":0.218392,"stage1_batch_id":"msgbatch_01DUPACZi7AAWwuZiUjseQF4","stage2_batch_id":"msgbatch_018yt7chE3f48PEFtDwtj6AE","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2004,\n      \"finding\": \"HtrA1 inhibits TGF-β family signaling by binding to a broad range of TGF-β family proteins (including BMP4, GDF5, TGFβs, and activin) via its protease domain and a linker region, preventing receptor activation; inhibition of TGFβ signaling is dependent on the proteolytic activity of HtrA1.\",\n      \"method\": \"GST-pulldown assay, deletion mutant analysis, cell-based signaling assay (C2C12 cells), chick embryo misexpression\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal binding assay, domain deletion mutants, multiple TGFβ family members tested, in vivo phenotypic validation consistent with TGFβ inhibition\",\n      \"pmids\": [\"14973287\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"HtrA1 directly degrades fragments of amyloid precursor protein (APP); an HtrA1 inhibitor causes accumulation of Aβ in astrocyte cell culture supernatants, and HtrA1 colocalizes with β-amyloid deposits in human brain samples.\",\n      \"method\": \"In vitro protease assay, cell culture supernatant analysis with HtrA1 inhibitor, immunofluorescence colocalization in human brain tissue\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro substrate degradation combined with inhibitor cell culture experiment and tissue colocalization, single lab\",\n      \"pmids\": [\"15855271\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"HtrA1 inhibits mineral deposition by osteoblasts; both the protease domain and the PDZ domain are required for this inhibitory effect. HtrA1 cleaves extracellular matrix proteins decorin, fibronectin, and matrix Gla protein (MGP); cleavage of MGP requires both the protease and PDZ domains, whereas cleavage of decorin and fibronectin does not require the PDZ domain. Type I collagen is not cleaved.\",\n      \"method\": \"Overexpression and siRNA knockdown in 2T3 osteoblasts, recombinant HtrA1 domain mutant in vitro cleavage assays, mineralization assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro reconstitution with domain mutants, complementary overexpression and knockdown approaches, multiple substrates tested with defined domain requirements\",\n      \"pmids\": [\"18156628\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"Human HtrA1 associates with microtubules in a PDZ domain-dependent and nocodazole-sensitive manner; it localizes to centrosomes and newly polymerized microtubules during assembly, promotes microtubule assembly in vitro, cosediments and copurifies with microtubules, and directly binds purified α- and β-tubulins. Downregulation of HtrA1 promotes cell motility while overexpression attenuates it.\",\n      \"method\": \"Immunofluorescence, microtubule co-sedimentation assay, co-purification, immunoprecipitation (endogenous HtrA1 pulling down α-, β-, γ-tubulin), in vitro microtubule assembly assay, cell motility assay with KD/OE\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — multiple orthogonal methods (co-sedimentation, co-purification, direct binding to purified tubulins, IP, in vitro assembly), PDZ domain dependence shown, functional readout\",\n      \"pmids\": [\"19470753\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"HtrA1 expression is upregulated by cisplatin and paclitaxel treatment, resulting in limited autoproteolysis and activation of HtrA1. Active HtrA1 induces cell death in a serine protease-dependent manner and modulates chemotherapy-induced cytotoxicity.\",\n      \"method\": \"Forced expression and downregulation of HtrA1 in cancer cell lines, cytotoxicity assays, protease-inactive mutant comparison, Western blot for autoproteolysis\",\n      \"journal\": \"The Journal of clinical investigation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — gain/loss-of-function with defined readout, protease-inactive mutant control establishing protease dependence, single lab\",\n      \"pmids\": [\"16767218\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Human HTRA1 degrades aggregated and fibrillar tau protein; neuronal cells with elevated HTRA1 accumulate less tau and neurofibrillary tangles; HTRA1 mRNA and activity are upregulated in response to elevated tau concentrations.\",\n      \"method\": \"In vitro degradation assay with aggregated/fibrillar tau, cell-based assay with HTRA1 overexpression, patient brain analysis, activity measurement\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — in vitro reconstitution with tau fibrils, cell-based validation, single lab\",\n      \"pmids\": [\"22535953\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Crystal structures and SAXS analysis of HtrA1 reveal a rare tandem of IGFBP- and Kazal-like modules in the N-terminal domain; the protease active site adopts a competent conformation in the absence of substrate or inhibitor, suggesting a two-state equilibrium/conformational selection model for substrate binding. The N-terminal IGFBP- and Kazal-like modules have no detectable effect on protease activity.\",\n      \"method\": \"X-ray crystallography, SAXS, enzymatic activity assays, binding studies with domain variants\",\n      \"journal\": \"Structure\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure combined with enzymatic assays and SAXS; multiple orthogonal methods in single rigorous study\",\n      \"pmids\": [\"22578544\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"HtrA1 directly interacts with TSC2 (tuberin) but not TSC1 (hamartin); HtrA1 cleaves TSC2 both in vitro and in vivo, and alterations in HtrA1 expression cause changes in phosphorylation status of TSC2 downstream targets 4E-BP1 and S6K.\",\n      \"method\": \"Co-immunoprecipitation, colocalization, in vitro cleavage assay, in vivo cleavage assay, Western blot for downstream phosphorylation\",\n      \"journal\": \"Molecular cancer research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct binding and cleavage shown in vitro and in vivo, downstream pathway readout, single lab\",\n      \"pmids\": [\"20671064\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"HtrA1 is induced by oxidative stress and promotes premature cell senescence through the p38 MAPK pathway in a protease activity-dependent manner; protease-inactive HtrA1 (S328A mutant) does not accelerate senescence, and HtrA1-induced senescence is abrogated by p38 MAPK inhibition.\",\n      \"method\": \"Transient transfection of wild-type vs. protease-inactive HtrA1, H2O2-induced senescence in MEFs and ARPE-19 cells, SA-β-galactosidase assay, p38 MAPK inhibitor, HtrA1-/- MEFs comparison\",\n      \"journal\": \"Experimental eye research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — protease-inactive mutant control establishes catalytic dependence, pathway inhibitor confirms p38 MAPK requirement, single lab\",\n      \"pmids\": [\"23623979\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"HtrA1 activation is regulated by an allosteric inter-monomer communication mechanism within its trimer, independent of the PDZ domain. Inhibitor binding is precluded if HtrA1 monomers cannot communicate with each other. The HtrA1 trimer degrades complex extracellular fibrils including tubulin, amyloid beta, and tau.\",\n      \"method\": \"Biochemical allosteric assays, inhibitor binding studies with communication-defective mutants, in vitro fibril degradation assays\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — mechanistic allosteric model with mutant validation, multiple substrates tested, single lab\",\n      \"pmids\": [\"29093542\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"HTRA1 cleaves the Notch ligand JAG1 within its intracellular domain, leading to JAG1 protein degradation and enhancement of Delta/Notch signaling; HTRA1 physically interacts with JAG1. In HtrA1-deficient mice, endothelial Notch signaling is diminished and VEGF receptor-2 expression is increased in endothelial cells.\",\n      \"method\": \"Physical interaction assay, in vitro/in vivo cleavage of JAG1, siRNA knockdown and forced expression of HTRA1 in endothelial cells, constitutively active Notch1 rescue experiment, HtrA1-/- mouse analysis\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — direct substrate cleavage shown, physical interaction confirmed, epistasis via constitutively active Notch1 rescue, in vivo validation in knockout mice\",\n      \"pmids\": [\"29713059\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"HTRA1 processes extracellular matrix proteins EFEMP1 and TSP1 (novel substrates), in addition to previously known substrates LTBP-1 and clusterin, in retinal pigment epithelium cells.\",\n      \"method\": \"Proteomic comparison of RPE cells with/without high-risk HTRA1 genotype, in vitro HTRA1 cleavage assays for novel substrates\",\n      \"journal\": \"Aging cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — in vitro cleavage assay for two novel substrates, supported by proteomics, single lab\",\n      \"pmids\": [\"29730901\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"CADASIL brain vessels accumulate HTRA1 protein (4.9-fold enriched) co-localizing with Notch3ECD deposits, consistent with HTRA1 sequestration. Comparison with HTRA1 knockout mouse brain vessel proteome reveals 18 overlapping enriched proteins, several of which are confirmed as novel HTRA1 substrates by in vitro proteolysis assay, consistent with loss of HTRA1 function in CADASIL.\",\n      \"method\": \"Quantitative brain vessel proteomics, colocalization, HTRA1-/- mouse proteome comparison, in vitro proteolysis assay\",\n      \"journal\": \"Acta neuropathologica\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro substrate validation plus in vivo proteome comparison with knockout mice, single lab\",\n      \"pmids\": [\"29725820\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Loss of HTRA1 in vascular smooth muscle cells (VSMCs) increases JAG1 protein levels and NOTCH3 signaling activity, and also enhances TGFβ-SMAD2/3 signaling. Combined over-activation of NOTCH3 and TGFβ pathways leads to additive accumulation of HES/HEY transcriptional repressors, repressing contractile VSMC marker genes and resulting in an immature VSMC phenotype with impaired arterial vasoconstriction in Htra1-deficient mice.\",\n      \"method\": \"HtrA1-/- mouse analysis, VSMC differentiation assays, Notch3 and TGFβ pathway activation/inhibition, ex vivo vasoconstriction assay\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo knockout mouse with defined phenotype, pathway epistasis via pathway activation experiments, functional vasoconstriction readout, single lab\",\n      \"pmids\": [\"31796853\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"HTRA1 inhibits canonical Wnt/β-catenin signaling in both paracrine and autocrine manners; HTRA1 forms a complex with β-catenin and reduces the proliferation rates of cells, affecting expression of several Wnt target genes.\",\n      \"method\": \"Luciferase reporter assay for Wnt activity, co-immunoprecipitation of HTRA1 and β-catenin, cell proliferation assay, overexpression and knockdown\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 / Moderate — co-IP showing complex formation, Wnt reporter assay, functional proliferation readout, single lab\",\n      \"pmids\": [\"29269789\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"HtrA1 plays important roles in trophoblast differentiation from Tpbpa-positive precursors in the ectoplacental cone. HtrA1-/- mice show intrauterine growth retardation with reduced junctional zone size, aberrant labyrinth vascularization, decreased spongiotrophoblasts and glycogen trophoblasts, and impaired maternal artery remodeling.\",\n      \"method\": \"HtrA1-/- mouse knockout analysis, histology, immunostaining for trophoblast markers, vascular morphometry\",\n      \"journal\": \"Developmental biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic knockout with defined cellular and vascular phenotypes, in vivo, single lab\",\n      \"pmids\": [\"25446274\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"MiR-30e and miR-181d are posttranscriptional negative regulators of HtrA1 by binding to its 3' UTR; overexpression of HtrA1 in the developing forebrain recapitulates aspects of the Dicer-/- phenotype affecting radial glia proliferation, and in vivo overexpression of miR-30e and miR-181d in Dicer-/- forebrain rescues RG proliferation defects.\",\n      \"method\": \"3'UTR luciferase reporter assay, in vivo rescue experiment in Dicer-/- mice, forebrain overexpression of HtrA1\",\n      \"journal\": \"Cell death & disease\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — 3'UTR binding validated by reporter assay, in vivo rescue experiment, single lab\",\n      \"pmids\": [\"22854828\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"HTRA1 is epigenetically silenced in HCT116 colon carcinoma cells via the epigenetic adaptor protein MBD2; depletion of HTRA1 causes centrosome amplification and polyploidy in SW480 cells and primary MEFs.\",\n      \"method\": \"MBD2 knockdown/chromatin analysis, HTRA1 depletion by siRNA, centrosome counting, ploidy analysis\",\n      \"journal\": \"BMC cancer\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — epigenetic mechanism identified via MBD2, loss-of-function with cellular phenotype, single lab\",\n      \"pmids\": [\"27388476\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"IFN-γ negatively controls HTRA1 expression through activation of the p38 MAPK/STAT1 pathway; STAT1 directly binds the HTRA1 promoter after IFN-γ stimulation. Neutralization of HTRA1 reversed enhanced collagen-induced arthritis (CIA) frequency and severity in IFN-γ-deficient mice.\",\n      \"method\": \"Dual luciferase reporter assay, chromatin immunoprecipitation (ChIP), p38 MAPK pathway inhibition, IFN-γ-/- mouse model of CIA, anti-HTRA1 antibody neutralization\",\n      \"journal\": \"Journal of immunology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP demonstrates direct STAT1 promoter binding, in vivo neutralization rescue, single lab with multiple methods\",\n      \"pmids\": [\"24907345\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"The trimeric HtrA1 catalytic domain forms a cage-like inhibition complex with antibody 94 (IgG94): one Fab binds peripherally to each protomer via loops B and C of the catalytic domain, suggesting an allosteric inhibition mechanism. The IgG94 complex (636 kDa) consists of three centrally located IgG molecules coordinating two HtrA1_Cat trimers with all six active sites pointing inward.\",\n      \"method\": \"Negative-staining EM, biochemical complex characterization, epitope mapping, enzymatic activity assays\",\n      \"journal\": \"The Biochemical journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — EM structural characterization plus epitope mapping and activity assays, single lab\",\n      \"pmids\": [\"26385991\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"HTRA1 is identified as a novel podocyte antigen in a subset of patients with primary membranous nephropathy; anti-HTRA1 autoantibodies are predominantly IgG4, and HTRA1 is specifically detected within immune deposits in affected kidney tissue.\",\n      \"method\": \"Immunoblotting of glomerular proteins, differential immunoprecipitation, mass spectrometry, laser-capture microdissection, protein fragment microarray, biopsy immunostaining\",\n      \"journal\": \"Journal of the American Society of Nephrology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple converging antigen identification methods, tissue immunostaining in 14 patients, single study\",\n      \"pmids\": [\"33952630\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"HTRA1 inhibits aggregation of α-synuclein, FUS, and TDP-43; disaggregates preformed α-syn fibrils and converts them into non-seeding, non-toxic species; reduces endogenous α-syn seeding when HTRA1 is knocked down; targets the NAC domain of α-syn; and detoxifies α-syn fibrils in primary neurons. The protease domain is necessary and sufficient for inhibiting aggregation, but this activity is proteolytically independent.\",\n      \"method\": \"In vitro aggregation inhibition assay, fibril disaggregation assay, seeding assay, HTRA1 knockdown cell assay, domain deletion mutants, primary neuron toxicity assay\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro reconstitution with multiple aggregating proteins, domain dissection establishing protease-domain sufficiency and proteolysis independence, cell-based seeding assay, primary neuron validation\",\n      \"pmids\": [\"38499535\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Processed forms of HtrA1 are found intracellularly and intranuclearly; the active intranuclear form has an apparent molecular weight of ~29 kDa. HtrA1 is found associated with HPV E6 and E7 proteins, and HPV E6/E7 expression is associated with post-transcriptional upregulation of HtrA1 (notably the nuclear form).\",\n      \"method\": \"Cellular fractionation, immunoblotting for HtrA1 isoforms, co-immunoprecipitation with HPV E6/E7\",\n      \"journal\": \"Journal of cellular biochemistry\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — fractionation and single Co-IP, limited mechanistic follow-up, single lab\",\n      \"pmids\": [\"18452160\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"RUNX2 co-operates with EGR1 to co-repress Htra1 expression; RUNX2 binds to Htra1 enhancers (seven validated by dual-luciferase assay), and Re-ChIP assays confirm co-occupancy of RUNX2 and EGR1 at these sites. Co-repression of Htra1 by RUNX2/EGR1 is associated with increased expression of osteoblast differentiation markers.\",\n      \"method\": \"ChIP-seq, dual-luciferase enhancer assays, Re-ChIP, RNA-seq, siRNA knockdown\",\n      \"journal\": \"Journal of cellular physiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP-seq plus Re-ChIP confirms co-occupancy, multiple enhancers validated by reporter assay, single lab\",\n      \"pmids\": [\"32324256\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"HTRA1 interacts with SLC7A11 (xCT) through its Kazal structural domain and upregulates SLC7A11 expression, thereby inhibiting ferroptosis and contributing to chemoresistance to 5-FU/L-OHP in colorectal cancer cells.\",\n      \"method\": \"Co-immunoprecipitation, domain mapping (Kazal domain), gain/loss-of-function, ROS and MDA measurement, electron microscopy for mitochondria, cell viability assays\",\n      \"journal\": \"Cell death discovery\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single Co-IP with domain mapping, single lab, no in vitro reconstitution of direct binding\",\n      \"pmids\": [\"38740771\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"HtrA1 regulates astrocyte differentiation and injury response: genetic deletion of HtrA1 during gliogenesis accelerates astrocyte differentiation, and HtrA1-ablated astrocytes show altered chondroitin sulfate proteoglycan expression, inhibition of neurite extension, and elevated TGF-β family proteins. Brain injury induces HtrA1 in reactive astrocytes and loss of HtrA1 impairs wound closure.\",\n      \"method\": \"HtrA1 genetic deletion in mice, astrocyte culture with HtrA1 ablation, neurite extension assay, injury response assay, immunostaining\",\n      \"journal\": \"The Journal of neuroscience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo genetic deletion with defined cellular phenotypes and TGFβ pathway link, single lab\",\n      \"pmids\": [\"29483282\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"HTRA1 is a homotrimeric serine protease that is activated by an allosteric inter-monomer communication mechanism and whose PDZ domain regulates substrate access; it cleaves a broad range of extracellular substrates (TGF-β family ligands, APP fragments, ECM proteins including decorin, fibronectin, MGP, EFEMP1, TSP1, LTBP-1) to modulate TGF-β/BMP, Notch/JAG1, and Wnt/β-catenin signaling, and intracellularly degrades aggregated tau and α-synuclein fibrils in a proteolysis-independent disaggregation mode, while also associating with microtubules via its PDZ domain to regulate cell motility.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"HTRA1 is a homotrimeric, secreted serine protease that regulates extracellular signaling and matrix homeostasis by proteolytically processing a broad set of substrates, and that secondarily moonlights as a chaperone-like disaggregase and microtubule-associated protein [#0, #2, #21, #3]. Its protease domain binds and antagonizes TGF-\\u03b2 family ligands (BMP4, GDF5, TGF\\u03b2s, activin) in a proteolysis-dependent manner to block receptor activation [#0], and it cleaves extracellular matrix and matricellular substrates including decorin, fibronectin, matrix Gla protein, EFEMP1, TSP1, and LTBP-1, with substrate-specific dependence on its regulatory PDZ domain [#2, #11]. Through cleavage of the Notch ligand JAG1 within its intracellular domain, HTRA1 promotes JAG1 degradation and tunes Notch3 signaling, and loss of HTRA1 in vascular smooth muscle cells de-represses both JAG1/NOTCH3 and TGF\\u03b2-SMAD2/3 signaling, driving HES/HEY-mediated repression of contractile genes and impaired vasoconstriction [#10, #13]; HTRA1 also restrains canonical Wnt/\\u03b2-catenin signaling and forms a complex with \\u03b2-catenin [#14]. Catalytically, HTRA1 adopts an active-competent conformation even without substrate, and trimer activation proceeds through allosteric inter-monomer communication independent of the PDZ domain [#6, #9]. Beyond proteolysis, HTRA1 disaggregates amyloidogenic protein fibrils\\u2014degrading aggregated tau and, via its protease domain in a proteolysis-independent mode, disaggregating \\u03b1-synuclein, FUS, and TDP-43 into non-seeding, non-toxic species [#5, #21]\\u2014and associates with microtubules and tubulin via its PDZ domain to limit cell motility [#3]. HTRA1 is induced by cellular stress and chemotherapeutics to drive protease-dependent cell death and p38 MAPK-dependent senescence [#4, #8], and is essential in vivo for trophoblast differentiation and placental vascular remodeling [#15].\",\n  \"teleology\": [\n    {\n      \"year\": 2004,\n      \"claim\": \"Established HTRA1 as a negative regulator of TGF-\\u03b2 family signaling, defining its first signaling role and showing this depends on its protease activity.\",\n      \"evidence\": \"GST-pulldown, domain deletion mutants, and C2C12 signaling assays with chick embryo misexpression\",\n      \"pmids\": [\"14973287\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether inhibition reflects ligand cleavage versus stoichiometric sequestration not fully resolved\", \"Physiological substrates among the tested ligands not pinpointed\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Linked HTRA1 proteolysis to amyloid biology by showing it degrades APP fragments and colocalizes with \\u03b2-amyloid deposits.\",\n      \"evidence\": \"In vitro protease assay, astrocyte supernatant analysis with HtrA1 inhibitor, human brain immunofluorescence\",\n      \"pmids\": [\"15855271\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Cleavage sites and physiological relevance to A\\u03b2 clearance not defined\", \"Single lab\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Defined HTRA1 as an ECM-processing protease and dissected differential PDZ-domain requirements across substrates, linking it to mineralization control.\",\n      \"evidence\": \"Osteoblast overexpression/knockdown plus recombinant domain-mutant in vitro cleavage of decorin, fibronectin, and MGP\",\n      \"pmids\": [\"18156628\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanistic basis for PDZ-dependence of MGP versus PDZ-independence of decorin/fibronectin unclear\", \"Cleavage product fate in vivo not tracked\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Revealed a non-proteolytic cytoskeletal role: HTRA1 binds tubulin via its PDZ domain, promotes microtubule assembly, and suppresses cell motility.\",\n      \"evidence\": \"Co-sedimentation, co-purification, direct tubulin binding, IP, in vitro assembly, and KD/OE motility assays\",\n      \"pmids\": [\"19470753\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Relationship between cytoplasmic microtubule role and secreted protease function unresolved\", \"Whether protease activity acts on microtubule-associated substrates unknown\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Connected HTRA1 to stress-induced cell fate, showing chemotherapeutics trigger its autoproteolytic activation and protease-dependent cell death.\",\n      \"evidence\": \"Gain/loss-of-function in cancer cells with protease-inactive mutant control and autoproteolysis Western blots\",\n      \"pmids\": [\"16767218\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Intracellular substrates mediating death not identified\", \"Single lab\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Implicated HTRA1 in mTOR pathway control via direct binding and cleavage of TSC2.\",\n      \"evidence\": \"Co-IP, in vitro/in vivo cleavage, and downstream 4E-BP1/S6K phosphorylation readouts\",\n      \"pmids\": [\"20671064\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"How a secreted protease accesses cytoplasmic TSC2 not reconciled\", \"Single lab\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Defined the structural basis of HTRA1 catalysis, showing the active site is competent without substrate, supporting a conformational-selection model.\",\n      \"evidence\": \"X-ray crystallography, SAXS, and enzymatic assays with domain variants\",\n      \"pmids\": [\"22578544\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional role of the IGFBP-/Kazal tandem module not established\", \"Full-length trimer architecture not solved\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Extended HTRA1 into tauopathy by showing it degrades aggregated/fibrillar tau and is upregulated by elevated tau.\",\n      \"evidence\": \"In vitro fibrillar-tau degradation, HTRA1-overexpressing neuronal cells, patient brain analysis\",\n      \"pmids\": [\"22535953\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of accessing intracellular tau unclear\", \"Single lab\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Linked HTRA1 to oxidative-stress-induced senescence through protease-dependent p38 MAPK activation.\",\n      \"evidence\": \"WT vs S328A protease-inactive HtrA1 in H2O2-treated MEFs/ARPE-19 with p38 inhibitor and HtrA1-/- comparison\",\n      \"pmids\": [\"23623979\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Substrate upstream of p38 not identified\", \"Single lab\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Established the trimer activation mechanism: allosteric inter-monomer communication, PDZ-independent, gates catalysis and fibril degradation.\",\n      \"evidence\": \"Allosteric assays, inhibitor binding with communication-defective mutants, fibril degradation assays\",\n      \"pmids\": [\"29093542\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Structural residues mediating communication not fully mapped\", \"Single lab\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Identified HTRA1 as an inhibitor of canonical Wnt/\\u03b2-catenin signaling acting both autocrine and paracrine.\",\n      \"evidence\": \"Wnt luciferase reporter, HTRA1\\u2013\\u03b2-catenin co-IP, proliferation assays with OE/KD\",\n      \"pmids\": [\"29269789\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether \\u03b2-catenin is a cleavage substrate or binding partner only is unclear\", \"Single co-IP without reciprocal validation\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Defined the JAG1/Notch axis: HTRA1 cleaves JAG1 to enhance Delta/Notch signaling and regulate endothelial VEGFR2, establishing a vascular signaling function.\",\n      \"evidence\": \"Physical interaction, in vitro/in vivo JAG1 cleavage, endothelial KD/OE, constitutively active Notch1 rescue, HtrA1-/- mice\",\n      \"pmids\": [\"29713059\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"JAG1 cleavage site within intracellular domain not mapped\", \"Topological basis for intracellular cleavage by a secreted protease unresolved\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Expanded the secreted-substrate repertoire to EFEMP1 and TSP1 in retinal pigment epithelium, linking genotype to altered ECM processing.\",\n      \"evidence\": \"RPE proteomics by HTRA1 genotype plus in vitro cleavage of novel substrates\",\n      \"pmids\": [\"29730901\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional consequences of EFEMP1/TSP1 cleavage in vivo not established\", \"Single lab\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Connected HTRA1 to cerebral small-vessel disease, showing HTRA1 sequestration on Notch3ECD deposits in CADASIL and loss-of-function substrate accumulation.\",\n      \"evidence\": \"Quantitative brain vessel proteomics, colocalization, HTRA1-/- proteome comparison, in vitro proteolysis\",\n      \"pmids\": [\"29725820\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Causal contribution of sequestration to disease progression not proven\", \"Single lab\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Integrated HTRA1's JAG1/NOTCH3 and TGF\\u03b2 functions into a vascular phenotype, explaining how its loss drives immature VSMCs and impaired vasoconstriction.\",\n      \"evidence\": \"HtrA1-/- mice, VSMC differentiation, Notch3/TGF\\u03b2 pathway manipulation, ex vivo vasoconstriction\",\n      \"pmids\": [\"31796853\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Relative contribution of the two pathways not quantified\", \"Single lab\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Defined a proteolysis-independent disaggregase activity: the HTRA1 protease domain alone inhibits and reverses \\u03b1-synuclein, FUS, and TDP-43 aggregation into non-toxic species.\",\n      \"evidence\": \"In vitro aggregation/disaggregation/seeding assays, domain deletions, HTRA1 KD, primary neuron toxicity\",\n      \"pmids\": [\"38499535\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis for proteolysis-independent NAC-domain targeting unresolved\", \"In vivo neuroprotective relevance not established\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How HTRA1's multiple compartmental activities\\u2014secreted ECM/ligand proteolysis, cytoplasmic/intracellular substrate cleavage, microtubule binding, and proteolysis-independent disaggregation\\u2014are coordinated within a single protein remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unified model reconciling extracellular and intracellular pools\", \"Mechanism switching between proteolytic and disaggregase modes unknown\", \"Spatial regulation of substrate selection undefined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [0, 2, 7, 10, 11]},\n      {\"term_id\": \"GO:0016787\", \"supporting_discovery_ids\": [2, 5, 10, 11]},\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [3]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [0, 21]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005576\", \"supporting_discovery_ids\": [0, 2, 11]},\n      {\"term_id\": \"GO:0005856\", \"supporting_discovery_ids\": [3]},\n      {\"term_id\": \"GO:0005815\", \"supporting_discovery_ids\": [3]},\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [22]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 10, 13, 14]},\n      {\"term_id\": \"R-HSA-1474244\", \"supporting_discovery_ids\": [2, 11]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [13, 15, 25]},\n      {\"term_id\": \"R-HSA-8953897\", \"supporting_discovery_ids\": [4, 8]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"JAG1\", \"TSC2\", \"CTNNB1\", \"TUBA\", \"TUBB\", \"SLC7A11\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}