{"gene":"HYOU1","run_date":"2026-06-10T01:55:22","timeline":{"discoveries":[{"year":1996,"finding":"ORP150 (HYOU1) is a novel ~150 kDa stress protein that localizes to the endoplasmic reticulum of astrocytes, is induced de novo by hypoxia at the transcriptional level (confirmed by nuclear run-off analysis), and its expression is selective for oxygen deprivation (not induced by heat shock, hydrogen peroxide, cobalt chloride, 2-deoxyglucose, or tunicamycin in astrocytes).","method":"Protein purification (FPLC/preparative SDS-PAGE), N-terminal sequencing, antisera generation, subcellular fractionation, Northern blot, nuclear run-off analysis, cycloheximide inhibition","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — protein purified to homogeneity, N-terminal sequence determined, subcellular localization by fractionation, transcriptional induction confirmed by nuclear run-off; foundational characterization paper","pmids":["8617779"],"is_preprint":false},{"year":1997,"finding":"Human ORP150 cDNA encodes a 999-residue protein containing an N-terminal signal peptide, a C-terminal ER retention-like signal, and an N-terminal half with significant similarity to the ATPase domain of HSP70 family proteins including conserved ATP-binding motifs, establishing it as a member of the HSP70 superfamily residing in the ER.","method":"cDNA cloning, deduced amino acid sequence analysis, Northern blot","journal":"Biochemical and biophysical research communications","confidence":"High","confidence_rationale":"Tier 1 / Strong — full cDNA cloning with domain architecture determination; replicated by multiple subsequent studies","pmids":["9020069"],"is_preprint":false},{"year":1999,"finding":"Grp170 (HYOU1) binds peptides translocated into microsomes by TAP in an ATP-independent manner, identifying it as a peptide-binding ER chaperone with substrate specificity overlapping but not identical to other ER chaperones (PDI, gp96, ERp72, calnexin).","method":"TAP-mediated peptide translocation into microsomes, peptide-binding assay, substrate specificity comparison","journal":"Biochemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct peptide-binding assay in microsomes with substrate selectivity analysis, single lab","pmids":["10441153"],"is_preprint":false},{"year":1999,"finding":"Suppression of ORP150 expression by stable antisense RNA transfection in HEK cells leads to reduced cell viability and accelerated apoptosis specifically under hypoxia, but not in response to oxygen-free radicals or sodium arsenate, establishing a specific cytoprotective function for ORP150 in hypoxia-induced cell death.","method":"Stable antisense RNA transfection, viability assays, apoptosis assays, caspase activity measurement, cytochrome c immunostaining","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — stable antisense knockdown with specific hypoxia phenotype, multiple orthogonal readouts (viability, apoptosis, caspase), replicated concept across multiple subsequent papers","pmids":["10037731"],"is_preprint":false},{"year":2000,"finding":"ORP150 functions as a molecular chaperone in MDCK renal epithelial cells by binding to the secretory glycoprotein GP80/clusterin under hypoxia; inhibition of ORP150 causes retention of GP80 in the ER and delays its maturation. ORP150 binds ATP-agarose and hydrolyzes ATP to release substrate at lower ATP concentrations, consistent with ATP-regulated substrate release.","method":"Co-immunoprecipitation, metabolic pulse-chase labeling, affinity chromatography on ATP-agarose, ATP hydrolysis assay, stable antisense transfection","journal":"American journal of physiology. Cell physiology","confidence":"High","confidence_rationale":"Tier 1–2 / Moderate — direct substrate binding (Co-IP), functional chaperone assay (maturation delay), ATP-binding and hydrolysis demonstrated biochemically; multiple orthogonal methods","pmids":["10837345"],"is_preprint":false},{"year":2000,"finding":"Human ORP150 gene produces at least three distinct mRNA species via alternative promoters; the transcript beginning with exon 1B is preferentially induced by hypoxia or tunicamycin. In vitro translation of the third mRNA (starting from exon 2, immediately upstream of AUG) generates a cytosolic form of ORP150 lacking the signal peptide due to differential translation initiation.","method":"Gene cloning and sequencing, transcription initiation site mapping, in vitro transcription/translation, Northern blot","journal":"Journal of biochemistry","confidence":"Medium","confidence_rationale":"Tier 1–2 / Moderate — in vitro translation demonstrating cytosolic isoform, promoter mapping with stress induction analysis, single lab","pmids":["10965054"],"is_preprint":false},{"year":2001,"finding":"ORP150 overexpression in neurons suppresses caspase-3-like activity and enhances BDNF under hypoxia signaling; targeted neuronal overexpression in mice results in smaller infarct volumes after ischemia, while astrocytes with inhibited ORP150 expression are more vulnerable to hypoxic stress.","method":"Transgenic mouse overexpression, adenoviral gene delivery, caspase activity assay, BDNF measurement, stroke model (MCA occlusion), antisense inhibition","journal":"Nature medicine","confidence":"High","confidence_rationale":"Tier 2 / Strong — in vivo transgenic and knockout models with mechanistic readouts (caspase-3, BDNF), replicated across multiple papers","pmids":["11231630"],"is_preprint":false},{"year":2001,"finding":"ORP150 acts as an intracellular chaperone facilitating VEGF secretion; inhibition of ORP150 in cultured human macrophages causes retention of VEGF within the ER, while ORP150 overexpression promotes VEGF secretion. Local adenoviral delivery of ORP150 to wound macrophages in diabetic mice increases VEGF levels and accelerates wound healing.","method":"Adenoviral gene delivery (sense/antisense), immunostaining for ER retention, VEGF ELISA in conditioned medium, wound healing model in diabetic mice","journal":"The Journal of clinical investigation","confidence":"High","confidence_rationale":"Tier 2 / Strong — ORP150 gain- and loss-of-function with direct VEGF secretion readout in vitro and in vivo, colocalization of ORP150 and VEGF, multiple labs replicating VEGF-ORP150 link","pmids":["11435456"],"is_preprint":false},{"year":2001,"finding":"ORP150 regulates cytosolic free calcium homeostasis in hippocampal neurons; ORP150 heterozygous-deficient mice show exaggerated cytosolic calcium elevation, enhanced mu-calpain and cathepsin B activation, and increased vulnerability to glutamate-induced cell death, while ORP150-overexpressing mice show suppression of these events.","method":"ORP150 heterozygous knockout mice, ORP150 transgenic mice, kainate model, cytosolic calcium measurement, mu-calpain and cathepsin B activity assays, in vitro glutamate toxicity","journal":"The Journal of clinical investigation","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal genetic models (heterozygous KO and transgenic OE) with specific mechanistic readouts (calcium, calpain, cathepsin), replicated in vivo and in vitro","pmids":["11714735"],"is_preprint":false},{"year":2002,"finding":"A cytoplasmic N-terminally truncated form of ORP150, lacking the ER signal peptide, is a major intracellular ligand for mushroom Agaricus bisporus lectin and is required for nuclear localization sequence (NLS)-dependent nuclear protein import; this cytoplasmic form expresses the lectin carbohydrate ligand (sialyl-2,3-galactosyl-β1,3-N-acetylgalactosamine-α).","method":"Lectin affinity chromatography, immunoprecipitation, NLS-dependent import assay, carbohydrate epitope characterization","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — biochemical isolation of cytoplasmic isoform, functional import assay, single lab with multiple methods","pmids":["11960996"],"is_preprint":false},{"year":2003,"finding":"Mouse Grp170 (HYOU1) functions as a molecular chaperone by maintaining heat-denatured luciferase in a soluble state in the absence of ATP (holdase activity), and can partially refold denatured luciferase in the presence of reticulocyte lysate. Domain deletion studies show two distinct substrate-binding regions: one homologous to the β-sandwich peptide-binding domain and a C-terminal α-helical domain, the latter being a unique substrate-binding feature not found in conventional Hsp70s.","method":"Recombinant protein expression (baculovirus), in vitro luciferase aggregation suppression assay, refolding assay, domain deletion mutagenesis","journal":"Biochemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution of chaperone activity with domain mutagenesis, multiple orthogonal assays in single study","pmids":["14674765"],"is_preprint":false},{"year":2005,"finding":"Grp170 (HYOU1) interacts with α1-antitrypsin Z (α1-AT Z) and other ER-retained α1-AT mutants in the ER, as demonstrated by chemical cross-linking and co-immunoprecipitation. Approximately 85% of α1-AT Z exists in soluble complexes with multiple chaperones (Grp78, Grp94, calnexin, Grp170, UDP-glucose glycoprotein:glucosyltransferase), while ~15% forms large polymers/aggregates devoid of chaperones.","method":"Chemical cross-linking, sequential immunoprecipitation/immunoblot, co-immunoprecipitation, sucrose density gradient centrifugation","journal":"American journal of physiology. Gastrointestinal and liver physiology","confidence":"High","confidence_rationale":"Tier 1–2 / Moderate — chemical cross-linking plus reciprocal Co-IP confirmed complex; sucrose gradient defines stoichiometry; multiple orthogonal methods in one study","pmids":["15845869"],"is_preprint":false},{"year":2006,"finding":"Mammalian Grp170 acts as a nucleotide exchange factor (NEF) for BiP, catalyzing ADP release and nucleotide exchange, analogous to yeast Lhs1p. This activity likely compensates for loss of the other BiP NEF, Sil1, in cells of most tissues, explaining why SIL1 mutations (Marinesco-Sjögren syndrome) cause a non-lethal, tissue-restricted phenotype.","method":"Biochemical nucleotide exchange assay, functional complementation analysis","journal":"FEBS letters","confidence":"High","confidence_rationale":"Tier 1 / Strong — direct biochemical NEF activity assay; independently replicated by multiple labs establishing Grp170 as BiP NEF","pmids":["16962589"],"is_preprint":false},{"year":2006,"finding":"The immunoadjuvant activity of Grp170 (HYOU1) directly correlates with its chaperoning function; domain deletion mutants that lose chaperone activity also lose the ability to bind antigen-presenting cells (APCs) in a receptor-mediated manner and to stimulate antitumor immunity. Grp170 interaction with APCs is mediated by its chaperoning domain, not a separate sequence-specific receptor-binding domain.","method":"Domain deletion mutagenesis, in vitro chaperone assay, APC receptor-binding assay, antigen presentation assay, in vivo tumor immunization","journal":"Cancer research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — structure-function with domain mutants, multiple functional readouts (chaperone activity, APC binding, immune response), single lab","pmids":["16424054"],"is_preprint":false},{"year":2007,"finding":"Grp170 (HYOU1) binds to scavenger receptor class A (SR-A) and scavenger receptor expressed by endothelial cells-I (SREC-I) on antigen-presenting cells in a saturable, receptor-mediated manner; scavenger receptor ligands inhibit this binding. SR-A and SREC-I mediate the cross-presentation of Grp170-chaperoned antigen to CD8+ T cells.","method":"Binding assay on SR-A- and SREC-I-expressing CHO cells, competitive inhibition with scavenger receptor ligands, IFN-γ ELISpot with T cells, bone marrow-derived dendritic cell binding","journal":"European journal of immunology","confidence":"High","confidence_rationale":"Tier 2 / Strong — saturable receptor binding on defined receptor-expressing cells, competitive inhibition, functional T-cell readout, multiple receptor types confirmed","pmids":["17615582"],"is_preprint":false},{"year":2007,"finding":"ORP150 localizes to mitochondria in addition to the ER: the N-terminal 13 amino acids are sufficient for mitochondrial targeting, as demonstrated by GFP-fusion constructs. Mitochondrial ORP150 is upregulated by anti-CHOP/GADD153 transcription factor. ORP150 is a substrate for mitochondrial calpain 10; calcium-induced calpain 10 activity cleaves ORP150 in isolated mitochondria.","method":"Subcellular fractionation, GFP-fusion live imaging, N-terminal deletion mutagenesis, Western blot (mitochondrial fractions), calpain inhibitor experiments, in vitro cleavage assay","journal":"American journal of physiology. Cell physiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — GFP fusion confirms mitochondrial targeting; N-terminal 13 aa sufficiency shown by truncation; calpain cleavage shown biochemically; single lab","pmids":["18094145"],"is_preprint":false},{"year":2013,"finding":"Grp170 (HYOU1) directly binds incompletely folded (unfolded) protein substrates in the ER but not folded secretory proteins. Unlike BiP (conventional Hsp70), Grp170 remains bound to substrates in the presence of ATP. The extended C-terminal α-helical domain is required for full substrate binding (deletion reduces interaction), while the unstructured loop in the putative substrate-binding domain suppresses binding (deletion increases interaction), revealing unique intramolecular regulation of large Hsp70 chaperone activity.","method":"Co-immunoprecipitation with unfolded vs. folded substrates, ATP-release assay, domain deletion mutagenesis (α-helical domain, unstructured loop), comparative analysis with BiP","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — direct substrate binding assay with folded/unfolded controls, ATP-sensitivity comparison, structure-function with two distinct domain deletions; multiple orthogonal methods in single study","pmids":["24327659"],"is_preprint":false},{"year":2013,"finding":"The yeast Lhs1/GRP170 ortholog facilitates ERAD of the ENaC α-subunit; the nucleotide exchange (NEF) activity of Lhs1 is dispensable for this function, but its holdase/chaperone activity is required. The mammalian homolog GRP170 co-precipitates with αENaC and facilitates ENaC degradation in HEK293 cells and Xenopus oocytes, selectively affecting the unglycosylated form of the protein.","method":"Yeast ENaC expression system, ATP-binding mutants of Lhs1, Co-immunoprecipitation (Lhs1-αENaC; GRP170-αENaC), degradation assay in HEK293 and Xenopus oocytes, glycosylation analysis","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP, functional ERAD assay in two mammalian systems, dissection of NEF vs holdase activity by mutagenesis, multiple orthogonal methods","pmids":["23645669"],"is_preprint":false},{"year":2015,"finding":"Grp170 (HYOU1) triggers nucleotide exchange on BiP (ADP→ATP), causing ATP-BiP to disengage from misfolded ERAD substrate NHK (null Hong Kong α1-antitrypsin), enabling NHK retrotranslocation to the cytosol. Grp170 physically binds to Sel1L (adapter of the Hrd1 E3 ubiquitin ligase/retrotranslocon), linking client release from BiP to retrotranslocation. Grp170 also promotes degradation of the non-glycosylated misfolded client TTR D18G.","method":"Loss- and gain-of-function approaches (siRNA/overexpression), co-immunoprecipitation (Grp170-Sel1L), retrotranslocation assay, cholera toxin (NHK) ERAD assay","journal":"Molecular biology of the cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — functional NEF-ERAD mechanism with substrate release and retrotranslocation assays, Sel1L binding confirmed by Co-IP, two distinct substrate clients, reciprocal gain/loss-of-function","pmids":["25877869"],"is_preprint":false},{"year":2016,"finding":"Grp170 (HYOU1) acts as a NEF for BiP to drive ERAD of the misfolded glycosylated client NHK: Grp170 converts ADP-BiP to ATP-BiP, releasing NHK to allow retrotranslocation through the Hrd1-Sel1L complex. Grp170 directly binds Sel1L, positioning client release at the retrotranslocation site to couple substrate disengagement from BiP with retrotranslocation.","method":"Knockdown and overexpression studies, binding assays (Grp170-Sel1L interaction), ERAD functional assay, NHK retrotranslocation assay","journal":"Molecular biology of the cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — mechanistic ERAD assay with Sel1L binding, NEF function directly demonstrated, two substrates tested, multiple complementary approaches","pmids":["27030672"],"is_preprint":false},{"year":2018,"finding":"AMPK activation induces ORP150 expression via the transcription factor FOXO1; lentiviral shRNA silencing of AMPK or FOXO1 reduces ORP150 levels and increases CHOP expression and ER stress-induced apoptosis in bronchial epithelial cells. FOXO1 is identified as a transcriptional regulator of ORP150.","method":"Pharmacological AMPK activation (AICAR), lentiviral shRNA knockdown of AMPK and FOXO1, Western blot, Annexin V-PI flow cytometry apoptosis assay","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic knockdown of both pathway components with mechanistic readouts, single lab; FOXO1 as ORP150 transcriptional regulator established by epistasis","pmids":["29448096"],"is_preprint":false},{"year":2018,"finding":"ORP150 (HYOU1) physically interacts with and stabilizes BACE1 at the post-translational level; ORP150 promotes BACE1-mediated amyloid (Aβ42) processing and prevents CHIP-mediated BACE1 ubiquitin-dependent degradation. ORP150 and CHIP show mutual antagonism, inversely regulating each other under normal and stress conditions.","method":"Co-immunoprecipitation (ORP150-BACE1), siRNA knockdown, overexpression, Western blot for BACE1/Aβ42 levels, CHIP ubiquitination assay","journal":"Journal of cellular biochemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct protein interaction by Co-IP with gain- and loss-of-function mechanistic readouts; single lab, multiple methods","pmids":["29266373"],"is_preprint":false},{"year":2021,"finding":"Inhibition of HYOU1 expression in lung cancer multicellular tumor spheroids suppresses stemness and malignancy, facilitates apoptosis, and increases chemosensitivity. Mechanistically, HYOU1 inhibition decreases activity of the PI3K/AKT/mTOR pathway, placing HYOU1 upstream of PI3K/AKT/mTOR signaling in lung cancer cells.","method":"siRNA knockdown, multicellular tumor spheroid model, apoptosis assays, Western blot for PI3K/AKT/mTOR pathway components, chemosensitivity assay","journal":"Molecules and cells","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — knockdown with specific signaling pathway readout (PI3K/AKT/mTOR) and multiple cellular phenotype measurements; single lab","pmids":["33455947"],"is_preprint":false},{"year":2021,"finding":"HYOU1 silencing in papillary thyroid cancer cells promotes oxidative phosphorylation while inhibiting aerobic glycolysis by downregulating LDHB at the posttranscriptional level via increased miR-375-3p. LDHB mRNA 3'UTR is the indirect target of HYOU1 action; LDHB overexpression rescues the metabolic and pro-tumorigenic effects of HYOU1 knockdown.","method":"siRNA knockdown, Western blot, qRT-PCR, metabolic assays, miR-375-3p measurement, LDHB overexpression rescue experiment, proliferation/migration/invasion assays","journal":"Journal of cellular and molecular medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — pathway dissected with knockdown, rescue experiment, and miRNA measurement; single lab with multiple orthogonal approaches","pmids":["33792181"],"is_preprint":false},{"year":2022,"finding":"Nephron-specific GRP170 (HYOU1) knockout mice develop profound hypovolemia, hyperaldosteronemia, ion homeostasis dysregulation associated with loss of ENaC, and hallmarks of acute kidney injury with activation of the unfolded protein response (UPR), establishing GRP170 as an essential chaperone for kidney ENaC function and renal homeostasis.","method":"Inducible nephron-specific Cre/LoxP knockout mouse, electrolyte and kidney function measurements, ENaC Western blot, UPR marker analysis","journal":"JCI insight","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean conditional knockout with multiple specific physiological and molecular readouts (ENaC, UPR, electrolytes, AKI markers); replicated by subsequent paper (PMID 39556479)","pmids":["35104250"],"is_preprint":false},{"year":2023,"finding":"FUT2-mediated α-1,2-fucosylation of HYOU1 at the N-glycosylation site asparagine (Asn) 862 facilitates intestinal stem cell survival, self-renewal, and resistance to ER stress and inflammatory injury. FUT2 depletion in ISCs escalates LPS-induced ER stress via the IRE1/TRAF2/ASK1/JNK UPR branch; fucosylation of HYOU1 at Asn862 is the mediating modification.","method":"N-glycoproteomics, UEA-1 lectin chromatography, site-directed mutagenesis (Asn862), intestinal organoid assays, ISC-specific Fut2 knockout mice, flow cytometry, Western blot","journal":"Redox biology","confidence":"High","confidence_rationale":"Tier 1 / Moderate — site-directed mutagenesis identifies specific fucosylation site (Asn862), multiple orthogonal approaches (glycoproteomics, mutagenesis, organoid, in vivo KO), single lab","pmids":["36724577"],"is_preprint":false},{"year":2023,"finding":"METTL3-mediated m6A methylation of HYOU1 mRNA, read by IGF2BP3, increases HYOU1 mRNA stability and protein expression, conferring doxorubicin resistance in breast cancer cells. Knockdown of METTL3 or HYOU1 overcomes doxorubicin resistance.","method":"RIP assay, MeRIP assay, dual-luciferase reporter assay, siRNA knockdown, CCK-8 viability, Annexin V flow cytometry, Western blot, qRT-PCR","journal":"Biochimica et biophysica acta. General subjects","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — m6A modification site confirmed by MeRIP and RIP, IGF2BP3 reader identified; epistatic rescue experiments; single lab","pmids":["38103759"],"is_preprint":false},{"year":2024,"finding":"Loss of Grp170 (HYOU1) in mouse embryonic fibroblasts causes BiP to fractionate with insoluble material, increases steady-state BiP binding to clients with reduced client turnover, reduces solubility of aggregation-prone BiP substrates, and induces UPR activation, culminating in cell death. These effects establish that Grp170 is essential for BiP function and ER homeostasis.","method":"Conditional Cre/LoxP Grp170 knockout in MEFs (doxycycline-inducible), subcellular fractionation, co-immunoprecipitation (BiP-client), client degradation assay, UPR marker Western blot, cell death assay","journal":"Molecular biology of the cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — controlled inducible depletion, multiple molecular readouts for BiP function and ER homeostasis, mechanistic consequences directly measured; replicated by preprint PMID 37905119","pmids":["38446639"],"is_preprint":false},{"year":2025,"finding":"Thyrocyte-specific loss of GRP170 (HYOU1) causes primary hypothyroidism with deficient TSH responsiveness. In cultured PCCL3 thyrocytes, GRP170 knockdown inhibits folding and forward trafficking of TSH receptors to the cell surface, establishing GRP170 as required for TSH receptor conformational maturation and thyroid hormone synthesis.","method":"Inducible Pax8-Cre thyroid-specific GRP170 knockout mice, siRNA knockdown in PCCL3 thyrocytes, TSH receptor surface trafficking assay, thyroid hormone measurements","journal":"JCI insight","confidence":"High","confidence_rationale":"Tier 2 / Strong — conditional in vivo KO with in vitro mechanistic follow-up (TSH receptor folding/trafficking), multiple complementary approaches, clean molecular phenotype","pmids":["40923318"],"is_preprint":false},{"year":2025,"finding":"Cryo-EM structure at 2.7 Å of the GRP170-ATP-BiP complex reveals a C-terminal curved hook domain in GRP170 that is proposed to engage substrate in coordination with BiP. The structure also reveals the structural basis for GRP170 pseudo-ATPase chaperone activity, making it the first chaperone of this type. The complex was purified from HEK293 cells.","method":"Cryo-electron microscopy (2.7 Å), protein complex purification from HEK293 cells","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — high-resolution cryo-EM structure is Tier 1 method, but this is a preprint without peer review and functional validation of hook domain is proposed rather than experimentally confirmed","pmids":["bio_10.1101_2025.10.25.684324"],"is_preprint":true},{"year":2016,"finding":"In thyroid cancer cells, ORP150 (HYOU1) transcription is induced by proteasome inhibition through two mechanisms: (1) Nrf2 directly binds and transactivates the −421/−307 region of the ORP150 promoter; (2) Nrf2 indirectly activates ORP150 via facilitating ATF4 recruitment to the −243/+53 region. Activating transcription factor 4 (ATF4) is required for ORP150 induction (siATF4 inhibits upregulation).","method":"Promoter deletion analysis, ChIP/reporter assay, siRNA knockdown of Nrf2 and ATF4, Western blot, real-time RT-PCR","journal":"Oncotarget","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — promoter binding by Nrf2 confirmed, ATF4 epistasis demonstrated by siRNA; single lab with multiple approaches","pmids":["26700459"],"is_preprint":false},{"year":2025,"finding":"CPE stabilizes HYOU1 protein by inhibiting ubiquitin-proteasome degradation; CPE deficiency causes reduced HYOU1 protein levels. In osteosarcoma cells, CPE activates Hippo-YAP signaling and promotes YAP nuclear translocation. Overexpression of HYOU1 rescues the anti-tumor and pro-PANoptosis effects of CPE knockdown, placing HYOU1 downstream of CPE in this pathway.","method":"CPE knockdown/knockout, HYOU1 overexpression rescue, proteasome inhibitor treatment, Western blot for ubiquitination and YAP pathway, xenograft tumor model, immunofluorescence for YAP localization","journal":"Cancer letters","confidence":"Low","confidence_rationale":"Tier 3 / Weak — CPE-HYOU1 epistasis suggested by rescue experiment but ubiquitination mechanism not directly shown for HYOU1; single lab, limited mechanistic depth for HYOU1 specifically","pmids":["41213463"],"is_preprint":false}],"current_model":"HYOU1/ORP150/GRP170 is an ER-resident large Hsp70 (Hsp110 family) that functions both as a holdase chaperone—binding unfolded or misfolded secretory proteins via two distinct substrate-binding domains (a β-sandwich domain and a unique C-terminal α-helical domain) in an ATP-independent manner—and as a nucleotide exchange factor (NEF) for the canonical ER Hsp70, BiP, converting ADP-BiP to ATP-BiP to release substrates for retrotranslocation during ERAD; GRP170 is physically anchored near the retrotranslocon by binding Sel1L, thereby coupling substrate release from BiP with retrotranslocation through the Hrd1-Sel1L complex. Beyond quality control, GRP170 is required for the folding and forward trafficking of specific clients including VEGF, TSH receptor, and ENaC, and regulates ER calcium homeostasis; its loss disrupts ER proteostasis, activates the UPR, and is lethal at the cellular and organismal level."},"narrative":{"mechanistic_narrative":"HYOU1 (ORP150/GRP170) is an ER-resident member of the HSP70 superfamily that functions as a stress-inducible molecular chaperone safeguarding secretory protein folding and ER proteostasis [PMID:9020069, PMID:14674765]. Originally isolated as a ~150 kDa hypoxia-induced ER stress protein in astrocytes, it is transcriptionally upregulated by oxygen deprivation and its loss accelerates hypoxia-specific apoptosis, defining a cytoprotective role under ER stress [PMID:8617779, PMID:10037731]. Biochemically it acts as an ATP-independent holdase: it binds unfolded—but not folded—secretory substrates and maintains denatured proteins in a soluble, refolding-competent state through two distinct substrate-binding regions, a β-sandwich peptide-binding domain and a unique C-terminal α-helical/hook domain, the latter not found in conventional Hsp70s [PMID:14674765, PMID:24327659]. In parallel it serves as a nucleotide exchange factor for the canonical ER Hsp70 BiP, catalyzing ADP→ATP exchange to release clients [PMID:16962589, PMID:25877869]; in ER-associated degradation it converts ADP-BiP to ATP-BiP to disengage misfolded substrates such as NHK α1-antitrypsin and physically binds the Hrd1 adaptor Sel1L, coupling client release from BiP to retrotranslocation through the Hrd1-Sel1L complex [PMID:25877869, PMID:27030672]. This dual activity makes GRP170 essential for BiP function and ER homeostasis: its loss in fibroblasts causes BiP and aggregation-prone clients to become insoluble, activates the UPR, and is lethal [PMID:38446639]. Beyond quality control, GRP170 chaperones specific secretory clients, promoting VEGF secretion [PMID:11435456] and the conformational maturation and surface trafficking of the ENaC channel and the TSH receptor, with tissue-specific knockout producing renal ion-homeostasis failure and primary hypothyroidism respectively [PMID:23645669, PMID:35104250, PMID:40923318]. It also regulates ER calcium homeostasis in neurons, limiting calpain/cathepsin activation and excitotoxic death [PMID:11714735]. Extracellularly, GRP170's chaperoning domain mediates receptor-bound (SR-A, SREC-I) uptake by antigen-presenting cells and cross-presentation, underlying its immunoadjuvant activity [PMID:16424054, PMID:17615582].","teleology":[{"year":1996,"claim":"Established the existence of a previously unknown ER stress protein selectively induced by hypoxia, defining HYOU1 as an oxygen-deprivation-responsive ER component distinct from heat-shock and other stress responses.","evidence":"Protein purification, N-terminal sequencing, subcellular fractionation and nuclear run-off in astrocytes","pmids":["8617779"],"confidence":"High","gaps":["Molecular function unknown at this stage","No substrate or partner identified","Sequence/domain identity not yet determined"]},{"year":1997,"claim":"Resolved the molecular identity of the protein by cloning the cDNA, revealing an ER-targeted HSP70-superfamily member with an ATPase-like domain and ER retention signal.","evidence":"cDNA cloning and deduced sequence/domain analysis","pmids":["9020069"],"confidence":"High","gaps":["Chaperone activity not functionally demonstrated","ATPase activity not biochemically tested","Client proteins unknown"]},{"year":1999,"claim":"Demonstrated that HYOU1 is a peptide-binding ER chaperone and that its loss specifically sensitizes cells to hypoxic death, linking biochemical substrate binding to a cytoprotective function.","evidence":"TAP-mediated microsomal peptide-binding assay; stable antisense knockdown with viability/apoptosis readouts","pmids":["10441153","10037731"],"confidence":"Medium","gaps":["Substrate selectivity defined only by comparison to a few ER chaperones","Mechanism of cytoprotection not at molecular resolution","ATP-dependence of binding not yet clarified"]},{"year":2000,"claim":"Identified a physiological folding client and probed ATP regulation, showing HYOU1 binds the secretory glycoprotein GP80/clusterin and binds/hydrolyzes ATP, with substrate release at low ATP.","evidence":"Co-IP, pulse-chase maturation assay, ATP-agarose binding and ATP hydrolysis assay in MDCK cells","pmids":["10837345"],"confidence":"High","gaps":["Relationship between ATP hydrolysis and holdase activity left ambiguous","Single client characterized","No structural basis for ATP handling"]},{"year":2001,"claim":"Established HYOU1 as a physiologically protective chaperone in vivo, controlling secretion of the angiogenic client VEGF and limiting ischemic/excitotoxic neuronal death via calcium and caspase regulation.","evidence":"Transgenic/heterozygous-KO mice, adenoviral delivery, stroke and wound-healing models, calcium and calpain/cathepsin assays","pmids":["11231630","11435456","11714735"],"confidence":"High","gaps":["Direct molecular link between HYOU1 and calcium handling not defined","Whether VEGF binding is direct chaperone-client engagement not shown","Mechanism connecting chaperone activity to caspase suppression unclear"]},{"year":2002,"claim":"Described a non-canonical cytoplasmic isoform lacking the signal peptide that participates in NLS-dependent nuclear import, expanding HYOU1 functions beyond the ER lumen.","evidence":"Lectin affinity purification, NLS-dependent import assay, carbohydrate epitope analysis","pmids":["11960996"],"confidence":"Medium","gaps":["Mechanism of nuclear import role undefined","Cytoplasmic isoform abundance/relevance in vivo unclear","Single-lab observation"]},{"year":2003,"claim":"Reconstituted chaperone activity in vitro and mapped two substrate-binding regions, establishing HYOU1 as an ATP-independent holdase with a unique C-terminal α-helical substrate-binding feature.","evidence":"Recombinant protein, luciferase aggregation-suppression and refolding assays, domain-deletion mutagenesis","pmids":["14674765"],"confidence":"High","gaps":["Structural basis of the α-helical domain not resolved","Refolding required lysate factors—co-chaperone dependence undefined","Physiological substrate spectrum not addressed"]},{"year":2006,"claim":"Defined a second core biochemical activity by showing HYOU1 acts as a nucleotide exchange factor for BiP, positioning it within the ER Hsp70 cycle alongside Sil1.","evidence":"Biochemical nucleotide exchange assay and functional complementation","pmids":["16962589"],"confidence":"High","gaps":["How NEF and holdase activities are coordinated unresolved","In-cell consequences of NEF activity not yet demonstrated","No structural model of GRP170-BiP engagement"]},{"year":2007,"claim":"Explained HYOU1's immunoadjuvant property mechanistically, showing its chaperoning domain mediates receptor-dependent (SR-A, SREC-I) uptake by APCs and cross-presentation to CD8+ T cells.","evidence":"Domain-deletion mutants, saturable receptor binding on receptor-expressing cells, competitive inhibition, T-cell IFN-γ readout","pmids":["16424054","17615582"],"confidence":"High","gaps":["Endogenous extracellular GRP170 role unclear","Physiological versus immunotherapeutic relevance not separated","Structural determinants of receptor binding undefined"]},{"year":2013,"claim":"Distinguished HYOU1 from BiP at the substrate level and defined intramolecular regulation, showing it binds only unfolded clients, remains bound in ATP, and that its α-helical domain promotes while an unstructured loop suppresses binding; also linked GRP170 holdase activity to ENaC ERAD.","evidence":"Co-IP with folded/unfolded substrates, ATP-release assay, domain-deletion mutants; yeast Lhs1 ENaC ERAD system with NEF vs holdase mutants and mammalian GRP170-αENaC Co-IP","pmids":["24327659","23645669"],"confidence":"High","gaps":["Which clients depend on holdase vs NEF activity not generalized","Structural mechanism of the regulatory loop unknown","Selectivity for unglycosylated ENaC form mechanistically unexplained"]},{"year":2016,"claim":"Integrated NEF activity into the ERAD pathway, showing GRP170 converts ADP-BiP to ATP-BiP to release misfolded clients and binds Sel1L to couple substrate disengagement with retrotranslocation through Hrd1-Sel1L.","evidence":"siRNA/overexpression, Grp170-Sel1L Co-IP, retrotranslocation and NHK/TTR ERAD assays","pmids":["25877869","27030672"],"confidence":"High","gaps":["Stoichiometry and spatial organization of GRP170-BiP-Sel1L not resolved","How holdase and NEF roles partition across glycosylated vs non-glycosylated clients unclear","In vivo requirement not yet established"]},{"year":2024,"claim":"Demonstrated that GRP170 is essential for BiP function and ER homeostasis at the whole-cell level, with its loss causing BiP and client insolubility, impaired client turnover, UPR activation, and death.","evidence":"Inducible conditional Grp170 knockout in MEFs, fractionation, BiP-client Co-IP, degradation and UPR/cell-death assays","pmids":["38446639"],"confidence":"High","gaps":["Which essential clients drive lethality unresolved","Separation of NEF vs holdase contributions to essentiality not achieved","Tissue-level consequences addressed separately"]},{"year":2025,"claim":"Tied GRP170's chaperone function to tissue-specific physiology, showing it is required for ENaC-dependent renal ion homeostasis and for TSH-receptor maturation and trafficking, with knockouts causing kidney injury and primary hypothyroidism.","evidence":"Nephron- and thyrocyte-specific inducible knockout mice with in vitro trafficking/maturation assays","pmids":["35104250","40923318"],"confidence":"High","gaps":["Direct chaperone engagement of TSHR/ENaC not shown structurally","Whether NEF or holdase activity is rate-limiting in vivo unclear","Full client repertoire across tissues unknown"]},{"year":2025,"claim":"Provided the first structural view of the GRP170-ATP-BiP complex, revealing a C-terminal curved hook domain and a structural basis for pseudo-ATPase chaperone activity.","evidence":"2.7 Å cryo-EM of complex purified from HEK293 cells (preprint)","pmids":["bio_10.1101_2025.10.25.684324"],"confidence":"Medium","gaps":["Preprint, not peer-reviewed","Hook-domain substrate engagement proposed but not functionally validated","Conformational dynamics of nucleotide exchange not resolved"]},{"year":null,"claim":"How GRP170 mechanistically partitions its holdase versus NEF activities across individual clients, and how the curved hook domain physically engages substrate during the BiP nucleotide cycle, remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No functional confirmation of the hook-domain substrate model","No comprehensive client repertoire mapping activity requirements","Coordination between substrate release and retrotranslocon engagement not structurally defined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0044183","term_label":"protein folding chaperone","supporting_discovery_ids":[10,16,4]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[12,18,19]},{"term_id":"GO:0140657","term_label":"ATP-dependent activity","supporting_discovery_ids":[4]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[16,17]}],"localization":[{"term_id":"GO:0005783","term_label":"endoplasmic reticulum","supporting_discovery_ids":[0,1,10,16]},{"term_id":"GO:0005739","term_label":"mitochondrion","supporting_discovery_ids":[15]}],"pathway":[{"term_id":"R-HSA-392499","term_label":"Metabolism of proteins","supporting_discovery_ids":[16,18,19,27]},{"term_id":"R-HSA-8953897","term_label":"Cellular responses to stimuli","supporting_discovery_ids":[0,3,27]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[13,14]}],"complexes":[],"partners":["HSPA5","SEL1L","BACE1","ENAC","TSHR"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9Y4L1","full_name":"Hypoxia up-regulated protein 1","aliases":["150 kDa oxygen-regulated protein","ORP-150","170 kDa glucose-regulated protein","GRP-170","Heat shock protein family H member 4"],"length_aa":999,"mass_kda":111.3,"function":"Has a pivotal role in cytoprotective cellular mechanisms triggered by oxygen deprivation. Promotes HSPA5/BiP-mediated ATP nucleotide exchange and thereby activates the unfolded protein response (UPR) pathway in the presence of endoplasmic reticulum stress (By similarity). May play a role as a molecular chaperone and participate in protein folding","subcellular_location":"Endoplasmic reticulum lumen","url":"https://www.uniprot.org/uniprotkb/Q9Y4L1/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":true,"resolved_as":"","url":"https://depmap.org/portal/gene/HYOU1","classification":"Common Essential","n_dependent_lines":1180,"n_total_lines":1208,"dependency_fraction":0.9768211920529801},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"CANX","stoichiometry":0.2},{"gene":"CCDC47","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/HYOU1","total_profiled":1310},"omim":[{"mim_id":"608005","title":"SIL1 NUCLEOTIDE EXCHANGE FACTOR; SIL1","url":"https://www.omim.org/entry/608005"},{"mim_id":"601746","title":"HYPOXIA UP-REGULATED 1; HYOU1","url":"https://www.omim.org/entry/601746"},{"mim_id":"248800","title":"MARINESCO-SJOGREN SYNDROME; MSS","url":"https://www.omim.org/entry/248800"},{"mim_id":"233600","title":"IMMUNODEFICIENCY 59 AND HYPOGLYCEMIA; IMD59","url":"https://www.omim.org/entry/233600"},{"mim_id":"138120","title":"HEAT-SHOCK 70-KD PROTEIN 5; HSPA5","url":"https://www.omim.org/entry/138120"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/HYOU1"},"hgnc":{"alias_symbol":["ORP150","HSP12A","Grp170"],"prev_symbol":[]},"alphafold":{"accession":"Q9Y4L1","domains":[{"cath_id":"3.30.420.40","chopping":"36-271_360-440","consensus_level":"medium","plddt":95.6544,"start":36,"end":440},{"cath_id":"3.90.640.10","chopping":"274-358","consensus_level":"high","plddt":96.2536,"start":274,"end":358},{"cath_id":"1.20.1270,1.20.1270","chopping":"729-799","consensus_level":"medium","plddt":93.9763,"start":729,"end":799},{"cath_id":"-","chopping":"815-911","consensus_level":"medium","plddt":91.1682,"start":815,"end":911},{"cath_id":"1.20.5","chopping":"2-31","consensus_level":"medium","plddt":63.111,"start":2,"end":31}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9Y4L1","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9Y4L1-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9Y4L1-F1-predicted_aligned_error_v6.png","plddt_mean":81.25},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=HYOU1","jax_strain_url":"https://www.jax.org/strain/search?query=HYOU1"},"sequence":{"accession":"Q9Y4L1","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9Y4L1.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9Y4L1/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9Y4L1"}},"corpus_meta":[{"pmid":"8617779","id":"PMC_8617779","title":"Purification and characterization of a novel stress protein, the 150-kDa oxygen-regulated protein (ORP150), from cultured rat astrocytes and its expression in ischemic mouse brain.","date":"1996","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/8617779","citation_count":171,"is_preprint":false},{"pmid":"11231630","id":"PMC_11231630","title":"ORP150 protects against hypoxia/ischemia-induced neuronal death.","date":"2001","source":"Nature medicine","url":"https://pubmed.ncbi.nlm.nih.gov/11231630","citation_count":171,"is_preprint":false},{"pmid":"25698114","id":"PMC_25698114","title":"BiP and its nucleotide exchange factors Grp170 and Sil1: mechanisms of action and biological functions.","date":"2015","source":"Journal of molecular biology","url":"https://pubmed.ncbi.nlm.nih.gov/25698114","citation_count":160,"is_preprint":false},{"pmid":"10037731","id":"PMC_10037731","title":"150-kDa oxygen-regulated protein (ORP150) suppresses hypoxia-induced apoptotic cell death.","date":"1999","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/10037731","citation_count":152,"is_preprint":false},{"pmid":"11435456","id":"PMC_11435456","title":"Expression of the oxygen-regulated protein ORP150 accelerates wound healing by modulating intracellular VEGF transport.","date":"2001","source":"The Journal of clinical investigation","url":"https://pubmed.ncbi.nlm.nih.gov/11435456","citation_count":124,"is_preprint":false},{"pmid":"11714735","id":"PMC_11714735","title":"Expression of the endoplasmic reticulum molecular chaperone (ORP150) rescues hippocampal neurons from glutamate toxicity.","date":"2001","source":"The Journal of clinical investigation","url":"https://pubmed.ncbi.nlm.nih.gov/11714735","citation_count":121,"is_preprint":false},{"pmid":"9020069","id":"PMC_9020069","title":"Cloning and expression of cDNA encoding the human 150 kDa oxygen-regulated protein, ORP150.","date":"1997","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/9020069","citation_count":86,"is_preprint":false},{"pmid":"15845869","id":"PMC_15845869","title":"Grp78, Grp94, and Grp170 interact with alpha1-antitrypsin mutants that are retained in the endoplasmic reticulum.","date":"2005","source":"American journal of physiology. 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HSPs, ORP-150 and COX2 are reliable markers to classify acute, perinatal events.","date":"2010","source":"Diagnostic pathology","url":"https://pubmed.ncbi.nlm.nih.gov/20626887","citation_count":11,"is_preprint":false},{"pmid":"12650521","id":"PMC_12650521","title":"Enforced expression of oxygen-regulated protein, ORP150, induces vacuolar degeneration in mouse myocardium.","date":"2003","source":"Transgenic research","url":"https://pubmed.ncbi.nlm.nih.gov/12650521","citation_count":10,"is_preprint":false},{"pmid":"21536389","id":"PMC_21536389","title":"Effects of ORP150 on appearance and function of pancreatic beta cells following acute necrotizing pancreatitis.","date":"2011","source":"Pathology, research and practice","url":"https://pubmed.ncbi.nlm.nih.gov/21536389","citation_count":10,"is_preprint":false},{"pmid":"22892132","id":"PMC_22892132","title":"Expression of 150-kDa oxygen-regulated protein (ORP150) stimulates bleomycin-induced pulmonary fibrosis and dysfunction in mice.","date":"2012","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/22892132","citation_count":8,"is_preprint":false},{"pmid":"30205291","id":"PMC_30205291","title":"Understanding the role of glucose regulated protein 170 (GRP170) as a nucleotide exchange factor through molecular simulations.","date":"2018","source":"Journal of molecular graphics & modelling","url":"https://pubmed.ncbi.nlm.nih.gov/30205291","citation_count":8,"is_preprint":false},{"pmid":"26700459","id":"PMC_26700459","title":"Involvement of Nrf2 in proteasome inhibition-mediated induction of ORP150 in thyroid cancer cells.","date":"2016","source":"Oncotarget","url":"https://pubmed.ncbi.nlm.nih.gov/26700459","citation_count":8,"is_preprint":false},{"pmid":"11913559","id":"PMC_11913559","title":"The increment of anti-ORP150 autoantibody in initial stages of atheroma in high-fat diet fed mice.","date":"2002","source":"The Journal of veterinary medical science","url":"https://pubmed.ncbi.nlm.nih.gov/11913559","citation_count":8,"is_preprint":false},{"pmid":"35398611","id":"PMC_35398611","title":"Abietic acid alleviates endoplasmic reticulum stress and lipid accumulation in human primary hepatocytes through the AMPK/ORP150 signaling.","date":"2022","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/35398611","citation_count":7,"is_preprint":false},{"pmid":"29266373","id":"PMC_29266373","title":"ORP150-CHIP chaperone antagonism control BACE1-mediated amyloid processing.","date":"2018","source":"Journal of cellular biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/29266373","citation_count":6,"is_preprint":false},{"pmid":"38339863","id":"PMC_38339863","title":"Discovery of the First-in-Class Inhibitors of Hypoxia Up-Regulated Protein 1 (HYOU1) Suppressing Pathogenic Fibroblast Activation.","date":"2024","source":"Angewandte Chemie (International ed. in English)","url":"https://pubmed.ncbi.nlm.nih.gov/38339863","citation_count":6,"is_preprint":false},{"pmid":"39556479","id":"PMC_39556479","title":"Excess dietary sodium restores electrolyte and water homeostasis caused by loss of the endoplasmic reticulum molecular chaperone, GRP170, in the mouse nephron.","date":"2024","source":"American journal of physiology. Renal physiology","url":"https://pubmed.ncbi.nlm.nih.gov/39556479","citation_count":6,"is_preprint":false},{"pmid":"18250584","id":"PMC_18250584","title":"Vacuolar degeneration of skeletal muscle in transgenic mice overexpressing ORP150.","date":"2008","source":"The Journal of veterinary medical science","url":"https://pubmed.ncbi.nlm.nih.gov/18250584","citation_count":6,"is_preprint":false},{"pmid":"36498988","id":"PMC_36498988","title":"Red Algae “Sarcodia suieae” Acetyl-Xylogalactan Downregulate Heat-Induced Macrophage Stress Factors Ddit3 and Hyou1 Compared to the Aquatic Animal Model of Nile Tilapia (Oreochromis niloticus) Brain Arachidonic Acid Expression.","date":"2022","source":"International journal of molecular sciences","url":"https://pubmed.ncbi.nlm.nih.gov/36498988","citation_count":4,"is_preprint":false},{"pmid":"12617037","id":"PMC_12617037","title":"[ORP150 (150 kDa oxygen regulated protein) suppressed neuronal cell death].","date":"2003","source":"Nihon yakurigaku zasshi. Folia pharmacologica Japonica","url":"https://pubmed.ncbi.nlm.nih.gov/12617037","citation_count":3,"is_preprint":false},{"pmid":"23894699","id":"PMC_23894699","title":"Engineering Grp170-based immune modulators for cancer immunotherapy.","date":"2013","source":"Oncoimmunology","url":"https://pubmed.ncbi.nlm.nih.gov/23894699","citation_count":3,"is_preprint":false},{"pmid":"17605339","id":"PMC_17605339","title":"Abetalipoproteinemia induced by overexpression of ORP150 in mice.","date":"2007","source":"Comparative medicine","url":"https://pubmed.ncbi.nlm.nih.gov/17605339","citation_count":3,"is_preprint":false},{"pmid":"40923318","id":"PMC_40923318","title":"Thyroidal expression of ER molecular chaperone GRP170 is required for efficient TSH-mediated thyroid hormone synthesis.","date":"2025","source":"JCI insight","url":"https://pubmed.ncbi.nlm.nih.gov/40923318","citation_count":2,"is_preprint":false},{"pmid":"37905119","id":"PMC_37905119","title":"Loss of Grp170 results in catastrophic disruption of endoplasmic reticulum functions.","date":"2023","source":"bioRxiv : the preprint server for biology","url":"https://pubmed.ncbi.nlm.nih.gov/37905119","citation_count":2,"is_preprint":false},{"pmid":"41213463","id":"PMC_41213463","title":"CPE/HYOU1 axis-activated Hippo-YAP signaling pathway suppresses PANoptosis to facilitate osteosarcoma progression.","date":"2025","source":"Cancer letters","url":"https://pubmed.ncbi.nlm.nih.gov/41213463","citation_count":1,"is_preprint":false},{"pmid":"38260467","id":"PMC_38260467","title":"Excess dietary sodium partially restores salt and water homeostasis caused by loss of the endoplasmic reticulum molecular chaperone, GRP170, in the mouse nephron.","date":"2024","source":"bioRxiv : the preprint server for biology","url":"https://pubmed.ncbi.nlm.nih.gov/38260467","citation_count":1,"is_preprint":false},{"pmid":"41405831","id":"PMC_41405831","title":"Endoplasmic reticulum stress upregulate HYOU1 and mediates lenvatinib resistance in liver cancer through ERK/MAPK pathway.","date":"2025","source":"Frontiers of medicine","url":"https://pubmed.ncbi.nlm.nih.gov/41405831","citation_count":0,"is_preprint":false},{"pmid":"35822684","id":"PMC_35822684","title":"The Clinical and Molecular Assessment of Iranian Families with Severe Congenital Neutropenia, Identification of HYOU1 and SHOC2 as Potential Novel Gene Defects.","date":"2022","source":"Iranian journal of allergy, asthma, and immunology","url":"https://pubmed.ncbi.nlm.nih.gov/35822684","citation_count":0,"is_preprint":false},{"pmid":"39650230","id":"PMC_39650230","title":"Overexpression of HYOU1 is associated with cisplatin resistance and may depend on m6A modification in patients with cervical cancer.","date":"2024","source":"Oncology letters","url":"https://pubmed.ncbi.nlm.nih.gov/39650230","citation_count":0,"is_preprint":false},{"pmid":"41583281","id":"PMC_41583281","title":"A Unique Pathogenic Heterozygous Hypoxia Up-Regulated Protein 1 (HYOU1) Mutation Presenting With Recurrent Osteomyelitis, Subglottic Stenosis, and Hypoglycemia.","date":"2025","source":"Cureus","url":"https://pubmed.ncbi.nlm.nih.gov/41583281","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.10.25.684324","title":"Structure of ER chaperone complex GRP170-ATP-BiP suggests a new model for substrate engagement","date":"2025-10-25","source":"bioRxiv","url":"https://doi.org/10.1101/2025.10.25.684324","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":41702,"output_tokens":8865,"usd":0.129041,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":18893,"output_tokens":4960,"usd":0.109232,"stage2_stop_reason":"end_turn"},"total_usd":0.238273,"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\": 1996,\n      \"finding\": \"ORP150 (HYOU1) is a novel ~150 kDa stress protein that localizes to the endoplasmic reticulum of astrocytes, is induced de novo by hypoxia at the transcriptional level (confirmed by nuclear run-off analysis), and its expression is selective for oxygen deprivation (not induced by heat shock, hydrogen peroxide, cobalt chloride, 2-deoxyglucose, or tunicamycin in astrocytes).\",\n      \"method\": \"Protein purification (FPLC/preparative SDS-PAGE), N-terminal sequencing, antisera generation, subcellular fractionation, Northern blot, nuclear run-off analysis, cycloheximide inhibition\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — protein purified to homogeneity, N-terminal sequence determined, subcellular localization by fractionation, transcriptional induction confirmed by nuclear run-off; foundational characterization paper\",\n      \"pmids\": [\"8617779\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1997,\n      \"finding\": \"Human ORP150 cDNA encodes a 999-residue protein containing an N-terminal signal peptide, a C-terminal ER retention-like signal, and an N-terminal half with significant similarity to the ATPase domain of HSP70 family proteins including conserved ATP-binding motifs, establishing it as a member of the HSP70 superfamily residing in the ER.\",\n      \"method\": \"cDNA cloning, deduced amino acid sequence analysis, Northern blot\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — full cDNA cloning with domain architecture determination; replicated by multiple subsequent studies\",\n      \"pmids\": [\"9020069\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1999,\n      \"finding\": \"Grp170 (HYOU1) binds peptides translocated into microsomes by TAP in an ATP-independent manner, identifying it as a peptide-binding ER chaperone with substrate specificity overlapping but not identical to other ER chaperones (PDI, gp96, ERp72, calnexin).\",\n      \"method\": \"TAP-mediated peptide translocation into microsomes, peptide-binding assay, substrate specificity comparison\",\n      \"journal\": \"Biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct peptide-binding assay in microsomes with substrate selectivity analysis, single lab\",\n      \"pmids\": [\"10441153\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1999,\n      \"finding\": \"Suppression of ORP150 expression by stable antisense RNA transfection in HEK cells leads to reduced cell viability and accelerated apoptosis specifically under hypoxia, but not in response to oxygen-free radicals or sodium arsenate, establishing a specific cytoprotective function for ORP150 in hypoxia-induced cell death.\",\n      \"method\": \"Stable antisense RNA transfection, viability assays, apoptosis assays, caspase activity measurement, cytochrome c immunostaining\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — stable antisense knockdown with specific hypoxia phenotype, multiple orthogonal readouts (viability, apoptosis, caspase), replicated concept across multiple subsequent papers\",\n      \"pmids\": [\"10037731\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"ORP150 functions as a molecular chaperone in MDCK renal epithelial cells by binding to the secretory glycoprotein GP80/clusterin under hypoxia; inhibition of ORP150 causes retention of GP80 in the ER and delays its maturation. ORP150 binds ATP-agarose and hydrolyzes ATP to release substrate at lower ATP concentrations, consistent with ATP-regulated substrate release.\",\n      \"method\": \"Co-immunoprecipitation, metabolic pulse-chase labeling, affinity chromatography on ATP-agarose, ATP hydrolysis assay, stable antisense transfection\",\n      \"journal\": \"American journal of physiology. Cell physiology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Moderate — direct substrate binding (Co-IP), functional chaperone assay (maturation delay), ATP-binding and hydrolysis demonstrated biochemically; multiple orthogonal methods\",\n      \"pmids\": [\"10837345\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"Human ORP150 gene produces at least three distinct mRNA species via alternative promoters; the transcript beginning with exon 1B is preferentially induced by hypoxia or tunicamycin. In vitro translation of the third mRNA (starting from exon 2, immediately upstream of AUG) generates a cytosolic form of ORP150 lacking the signal peptide due to differential translation initiation.\",\n      \"method\": \"Gene cloning and sequencing, transcription initiation site mapping, in vitro transcription/translation, Northern blot\",\n      \"journal\": \"Journal of biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1–2 / Moderate — in vitro translation demonstrating cytosolic isoform, promoter mapping with stress induction analysis, single lab\",\n      \"pmids\": [\"10965054\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"ORP150 overexpression in neurons suppresses caspase-3-like activity and enhances BDNF under hypoxia signaling; targeted neuronal overexpression in mice results in smaller infarct volumes after ischemia, while astrocytes with inhibited ORP150 expression are more vulnerable to hypoxic stress.\",\n      \"method\": \"Transgenic mouse overexpression, adenoviral gene delivery, caspase activity assay, BDNF measurement, stroke model (MCA occlusion), antisense inhibition\",\n      \"journal\": \"Nature medicine\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — in vivo transgenic and knockout models with mechanistic readouts (caspase-3, BDNF), replicated across multiple papers\",\n      \"pmids\": [\"11231630\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"ORP150 acts as an intracellular chaperone facilitating VEGF secretion; inhibition of ORP150 in cultured human macrophages causes retention of VEGF within the ER, while ORP150 overexpression promotes VEGF secretion. Local adenoviral delivery of ORP150 to wound macrophages in diabetic mice increases VEGF levels and accelerates wound healing.\",\n      \"method\": \"Adenoviral gene delivery (sense/antisense), immunostaining for ER retention, VEGF ELISA in conditioned medium, wound healing model in diabetic mice\",\n      \"journal\": \"The Journal of clinical investigation\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — ORP150 gain- and loss-of-function with direct VEGF secretion readout in vitro and in vivo, colocalization of ORP150 and VEGF, multiple labs replicating VEGF-ORP150 link\",\n      \"pmids\": [\"11435456\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"ORP150 regulates cytosolic free calcium homeostasis in hippocampal neurons; ORP150 heterozygous-deficient mice show exaggerated cytosolic calcium elevation, enhanced mu-calpain and cathepsin B activation, and increased vulnerability to glutamate-induced cell death, while ORP150-overexpressing mice show suppression of these events.\",\n      \"method\": \"ORP150 heterozygous knockout mice, ORP150 transgenic mice, kainate model, cytosolic calcium measurement, mu-calpain and cathepsin B activity assays, in vitro glutamate toxicity\",\n      \"journal\": \"The Journal of clinical investigation\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal genetic models (heterozygous KO and transgenic OE) with specific mechanistic readouts (calcium, calpain, cathepsin), replicated in vivo and in vitro\",\n      \"pmids\": [\"11714735\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"A cytoplasmic N-terminally truncated form of ORP150, lacking the ER signal peptide, is a major intracellular ligand for mushroom Agaricus bisporus lectin and is required for nuclear localization sequence (NLS)-dependent nuclear protein import; this cytoplasmic form expresses the lectin carbohydrate ligand (sialyl-2,3-galactosyl-β1,3-N-acetylgalactosamine-α).\",\n      \"method\": \"Lectin affinity chromatography, immunoprecipitation, NLS-dependent import assay, carbohydrate epitope characterization\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — biochemical isolation of cytoplasmic isoform, functional import assay, single lab with multiple methods\",\n      \"pmids\": [\"11960996\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"Mouse Grp170 (HYOU1) functions as a molecular chaperone by maintaining heat-denatured luciferase in a soluble state in the absence of ATP (holdase activity), and can partially refold denatured luciferase in the presence of reticulocyte lysate. Domain deletion studies show two distinct substrate-binding regions: one homologous to the β-sandwich peptide-binding domain and a C-terminal α-helical domain, the latter being a unique substrate-binding feature not found in conventional Hsp70s.\",\n      \"method\": \"Recombinant protein expression (baculovirus), in vitro luciferase aggregation suppression assay, refolding assay, domain deletion mutagenesis\",\n      \"journal\": \"Biochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution of chaperone activity with domain mutagenesis, multiple orthogonal assays in single study\",\n      \"pmids\": [\"14674765\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Grp170 (HYOU1) interacts with α1-antitrypsin Z (α1-AT Z) and other ER-retained α1-AT mutants in the ER, as demonstrated by chemical cross-linking and co-immunoprecipitation. Approximately 85% of α1-AT Z exists in soluble complexes with multiple chaperones (Grp78, Grp94, calnexin, Grp170, UDP-glucose glycoprotein:glucosyltransferase), while ~15% forms large polymers/aggregates devoid of chaperones.\",\n      \"method\": \"Chemical cross-linking, sequential immunoprecipitation/immunoblot, co-immunoprecipitation, sucrose density gradient centrifugation\",\n      \"journal\": \"American journal of physiology. Gastrointestinal and liver physiology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Moderate — chemical cross-linking plus reciprocal Co-IP confirmed complex; sucrose gradient defines stoichiometry; multiple orthogonal methods in one study\",\n      \"pmids\": [\"15845869\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"Mammalian Grp170 acts as a nucleotide exchange factor (NEF) for BiP, catalyzing ADP release and nucleotide exchange, analogous to yeast Lhs1p. This activity likely compensates for loss of the other BiP NEF, Sil1, in cells of most tissues, explaining why SIL1 mutations (Marinesco-Sjögren syndrome) cause a non-lethal, tissue-restricted phenotype.\",\n      \"method\": \"Biochemical nucleotide exchange assay, functional complementation analysis\",\n      \"journal\": \"FEBS letters\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — direct biochemical NEF activity assay; independently replicated by multiple labs establishing Grp170 as BiP NEF\",\n      \"pmids\": [\"16962589\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"The immunoadjuvant activity of Grp170 (HYOU1) directly correlates with its chaperoning function; domain deletion mutants that lose chaperone activity also lose the ability to bind antigen-presenting cells (APCs) in a receptor-mediated manner and to stimulate antitumor immunity. Grp170 interaction with APCs is mediated by its chaperoning domain, not a separate sequence-specific receptor-binding domain.\",\n      \"method\": \"Domain deletion mutagenesis, in vitro chaperone assay, APC receptor-binding assay, antigen presentation assay, in vivo tumor immunization\",\n      \"journal\": \"Cancer research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — structure-function with domain mutants, multiple functional readouts (chaperone activity, APC binding, immune response), single lab\",\n      \"pmids\": [\"16424054\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Grp170 (HYOU1) binds to scavenger receptor class A (SR-A) and scavenger receptor expressed by endothelial cells-I (SREC-I) on antigen-presenting cells in a saturable, receptor-mediated manner; scavenger receptor ligands inhibit this binding. SR-A and SREC-I mediate the cross-presentation of Grp170-chaperoned antigen to CD8+ T cells.\",\n      \"method\": \"Binding assay on SR-A- and SREC-I-expressing CHO cells, competitive inhibition with scavenger receptor ligands, IFN-γ ELISpot with T cells, bone marrow-derived dendritic cell binding\",\n      \"journal\": \"European journal of immunology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — saturable receptor binding on defined receptor-expressing cells, competitive inhibition, functional T-cell readout, multiple receptor types confirmed\",\n      \"pmids\": [\"17615582\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"ORP150 localizes to mitochondria in addition to the ER: the N-terminal 13 amino acids are sufficient for mitochondrial targeting, as demonstrated by GFP-fusion constructs. Mitochondrial ORP150 is upregulated by anti-CHOP/GADD153 transcription factor. ORP150 is a substrate for mitochondrial calpain 10; calcium-induced calpain 10 activity cleaves ORP150 in isolated mitochondria.\",\n      \"method\": \"Subcellular fractionation, GFP-fusion live imaging, N-terminal deletion mutagenesis, Western blot (mitochondrial fractions), calpain inhibitor experiments, in vitro cleavage assay\",\n      \"journal\": \"American journal of physiology. Cell physiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — GFP fusion confirms mitochondrial targeting; N-terminal 13 aa sufficiency shown by truncation; calpain cleavage shown biochemically; single lab\",\n      \"pmids\": [\"18094145\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Grp170 (HYOU1) directly binds incompletely folded (unfolded) protein substrates in the ER but not folded secretory proteins. Unlike BiP (conventional Hsp70), Grp170 remains bound to substrates in the presence of ATP. The extended C-terminal α-helical domain is required for full substrate binding (deletion reduces interaction), while the unstructured loop in the putative substrate-binding domain suppresses binding (deletion increases interaction), revealing unique intramolecular regulation of large Hsp70 chaperone activity.\",\n      \"method\": \"Co-immunoprecipitation with unfolded vs. folded substrates, ATP-release assay, domain deletion mutagenesis (α-helical domain, unstructured loop), comparative analysis with BiP\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — direct substrate binding assay with folded/unfolded controls, ATP-sensitivity comparison, structure-function with two distinct domain deletions; multiple orthogonal methods in single study\",\n      \"pmids\": [\"24327659\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"The yeast Lhs1/GRP170 ortholog facilitates ERAD of the ENaC α-subunit; the nucleotide exchange (NEF) activity of Lhs1 is dispensable for this function, but its holdase/chaperone activity is required. The mammalian homolog GRP170 co-precipitates with αENaC and facilitates ENaC degradation in HEK293 cells and Xenopus oocytes, selectively affecting the unglycosylated form of the protein.\",\n      \"method\": \"Yeast ENaC expression system, ATP-binding mutants of Lhs1, Co-immunoprecipitation (Lhs1-αENaC; GRP170-αENaC), degradation assay in HEK293 and Xenopus oocytes, glycosylation analysis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP, functional ERAD assay in two mammalian systems, dissection of NEF vs holdase activity by mutagenesis, multiple orthogonal methods\",\n      \"pmids\": [\"23645669\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"Grp170 (HYOU1) triggers nucleotide exchange on BiP (ADP→ATP), causing ATP-BiP to disengage from misfolded ERAD substrate NHK (null Hong Kong α1-antitrypsin), enabling NHK retrotranslocation to the cytosol. Grp170 physically binds to Sel1L (adapter of the Hrd1 E3 ubiquitin ligase/retrotranslocon), linking client release from BiP to retrotranslocation. Grp170 also promotes degradation of the non-glycosylated misfolded client TTR D18G.\",\n      \"method\": \"Loss- and gain-of-function approaches (siRNA/overexpression), co-immunoprecipitation (Grp170-Sel1L), retrotranslocation assay, cholera toxin (NHK) ERAD assay\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — functional NEF-ERAD mechanism with substrate release and retrotranslocation assays, Sel1L binding confirmed by Co-IP, two distinct substrate clients, reciprocal gain/loss-of-function\",\n      \"pmids\": [\"25877869\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"Grp170 (HYOU1) acts as a NEF for BiP to drive ERAD of the misfolded glycosylated client NHK: Grp170 converts ADP-BiP to ATP-BiP, releasing NHK to allow retrotranslocation through the Hrd1-Sel1L complex. Grp170 directly binds Sel1L, positioning client release at the retrotranslocation site to couple substrate disengagement from BiP with retrotranslocation.\",\n      \"method\": \"Knockdown and overexpression studies, binding assays (Grp170-Sel1L interaction), ERAD functional assay, NHK retrotranslocation assay\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — mechanistic ERAD assay with Sel1L binding, NEF function directly demonstrated, two substrates tested, multiple complementary approaches\",\n      \"pmids\": [\"27030672\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"AMPK activation induces ORP150 expression via the transcription factor FOXO1; lentiviral shRNA silencing of AMPK or FOXO1 reduces ORP150 levels and increases CHOP expression and ER stress-induced apoptosis in bronchial epithelial cells. FOXO1 is identified as a transcriptional regulator of ORP150.\",\n      \"method\": \"Pharmacological AMPK activation (AICAR), lentiviral shRNA knockdown of AMPK and FOXO1, Western blot, Annexin V-PI flow cytometry apoptosis assay\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic knockdown of both pathway components with mechanistic readouts, single lab; FOXO1 as ORP150 transcriptional regulator established by epistasis\",\n      \"pmids\": [\"29448096\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"ORP150 (HYOU1) physically interacts with and stabilizes BACE1 at the post-translational level; ORP150 promotes BACE1-mediated amyloid (Aβ42) processing and prevents CHIP-mediated BACE1 ubiquitin-dependent degradation. ORP150 and CHIP show mutual antagonism, inversely regulating each other under normal and stress conditions.\",\n      \"method\": \"Co-immunoprecipitation (ORP150-BACE1), siRNA knockdown, overexpression, Western blot for BACE1/Aβ42 levels, CHIP ubiquitination assay\",\n      \"journal\": \"Journal of cellular biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct protein interaction by Co-IP with gain- and loss-of-function mechanistic readouts; single lab, multiple methods\",\n      \"pmids\": [\"29266373\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"Inhibition of HYOU1 expression in lung cancer multicellular tumor spheroids suppresses stemness and malignancy, facilitates apoptosis, and increases chemosensitivity. Mechanistically, HYOU1 inhibition decreases activity of the PI3K/AKT/mTOR pathway, placing HYOU1 upstream of PI3K/AKT/mTOR signaling in lung cancer cells.\",\n      \"method\": \"siRNA knockdown, multicellular tumor spheroid model, apoptosis assays, Western blot for PI3K/AKT/mTOR pathway components, chemosensitivity assay\",\n      \"journal\": \"Molecules and cells\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — knockdown with specific signaling pathway readout (PI3K/AKT/mTOR) and multiple cellular phenotype measurements; single lab\",\n      \"pmids\": [\"33455947\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"HYOU1 silencing in papillary thyroid cancer cells promotes oxidative phosphorylation while inhibiting aerobic glycolysis by downregulating LDHB at the posttranscriptional level via increased miR-375-3p. LDHB mRNA 3'UTR is the indirect target of HYOU1 action; LDHB overexpression rescues the metabolic and pro-tumorigenic effects of HYOU1 knockdown.\",\n      \"method\": \"siRNA knockdown, Western blot, qRT-PCR, metabolic assays, miR-375-3p measurement, LDHB overexpression rescue experiment, proliferation/migration/invasion assays\",\n      \"journal\": \"Journal of cellular and molecular medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — pathway dissected with knockdown, rescue experiment, and miRNA measurement; single lab with multiple orthogonal approaches\",\n      \"pmids\": [\"33792181\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Nephron-specific GRP170 (HYOU1) knockout mice develop profound hypovolemia, hyperaldosteronemia, ion homeostasis dysregulation associated with loss of ENaC, and hallmarks of acute kidney injury with activation of the unfolded protein response (UPR), establishing GRP170 as an essential chaperone for kidney ENaC function and renal homeostasis.\",\n      \"method\": \"Inducible nephron-specific Cre/LoxP knockout mouse, electrolyte and kidney function measurements, ENaC Western blot, UPR marker analysis\",\n      \"journal\": \"JCI insight\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean conditional knockout with multiple specific physiological and molecular readouts (ENaC, UPR, electrolytes, AKI markers); replicated by subsequent paper (PMID 39556479)\",\n      \"pmids\": [\"35104250\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"FUT2-mediated α-1,2-fucosylation of HYOU1 at the N-glycosylation site asparagine (Asn) 862 facilitates intestinal stem cell survival, self-renewal, and resistance to ER stress and inflammatory injury. FUT2 depletion in ISCs escalates LPS-induced ER stress via the IRE1/TRAF2/ASK1/JNK UPR branch; fucosylation of HYOU1 at Asn862 is the mediating modification.\",\n      \"method\": \"N-glycoproteomics, UEA-1 lectin chromatography, site-directed mutagenesis (Asn862), intestinal organoid assays, ISC-specific Fut2 knockout mice, flow cytometry, Western blot\",\n      \"journal\": \"Redox biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — site-directed mutagenesis identifies specific fucosylation site (Asn862), multiple orthogonal approaches (glycoproteomics, mutagenesis, organoid, in vivo KO), single lab\",\n      \"pmids\": [\"36724577\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"METTL3-mediated m6A methylation of HYOU1 mRNA, read by IGF2BP3, increases HYOU1 mRNA stability and protein expression, conferring doxorubicin resistance in breast cancer cells. Knockdown of METTL3 or HYOU1 overcomes doxorubicin resistance.\",\n      \"method\": \"RIP assay, MeRIP assay, dual-luciferase reporter assay, siRNA knockdown, CCK-8 viability, Annexin V flow cytometry, Western blot, qRT-PCR\",\n      \"journal\": \"Biochimica et biophysica acta. General subjects\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — m6A modification site confirmed by MeRIP and RIP, IGF2BP3 reader identified; epistatic rescue experiments; single lab\",\n      \"pmids\": [\"38103759\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Loss of Grp170 (HYOU1) in mouse embryonic fibroblasts causes BiP to fractionate with insoluble material, increases steady-state BiP binding to clients with reduced client turnover, reduces solubility of aggregation-prone BiP substrates, and induces UPR activation, culminating in cell death. These effects establish that Grp170 is essential for BiP function and ER homeostasis.\",\n      \"method\": \"Conditional Cre/LoxP Grp170 knockout in MEFs (doxycycline-inducible), subcellular fractionation, co-immunoprecipitation (BiP-client), client degradation assay, UPR marker Western blot, cell death assay\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — controlled inducible depletion, multiple molecular readouts for BiP function and ER homeostasis, mechanistic consequences directly measured; replicated by preprint PMID 37905119\",\n      \"pmids\": [\"38446639\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Thyrocyte-specific loss of GRP170 (HYOU1) causes primary hypothyroidism with deficient TSH responsiveness. In cultured PCCL3 thyrocytes, GRP170 knockdown inhibits folding and forward trafficking of TSH receptors to the cell surface, establishing GRP170 as required for TSH receptor conformational maturation and thyroid hormone synthesis.\",\n      \"method\": \"Inducible Pax8-Cre thyroid-specific GRP170 knockout mice, siRNA knockdown in PCCL3 thyrocytes, TSH receptor surface trafficking assay, thyroid hormone measurements\",\n      \"journal\": \"JCI insight\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — conditional in vivo KO with in vitro mechanistic follow-up (TSH receptor folding/trafficking), multiple complementary approaches, clean molecular phenotype\",\n      \"pmids\": [\"40923318\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Cryo-EM structure at 2.7 Å of the GRP170-ATP-BiP complex reveals a C-terminal curved hook domain in GRP170 that is proposed to engage substrate in coordination with BiP. The structure also reveals the structural basis for GRP170 pseudo-ATPase chaperone activity, making it the first chaperone of this type. The complex was purified from HEK293 cells.\",\n      \"method\": \"Cryo-electron microscopy (2.7 Å), protein complex purification from HEK293 cells\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — high-resolution cryo-EM structure is Tier 1 method, but this is a preprint without peer review and functional validation of hook domain is proposed rather than experimentally confirmed\",\n      \"pmids\": [\"bio_10.1101_2025.10.25.684324\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"In thyroid cancer cells, ORP150 (HYOU1) transcription is induced by proteasome inhibition through two mechanisms: (1) Nrf2 directly binds and transactivates the −421/−307 region of the ORP150 promoter; (2) Nrf2 indirectly activates ORP150 via facilitating ATF4 recruitment to the −243/+53 region. Activating transcription factor 4 (ATF4) is required for ORP150 induction (siATF4 inhibits upregulation).\",\n      \"method\": \"Promoter deletion analysis, ChIP/reporter assay, siRNA knockdown of Nrf2 and ATF4, Western blot, real-time RT-PCR\",\n      \"journal\": \"Oncotarget\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — promoter binding by Nrf2 confirmed, ATF4 epistasis demonstrated by siRNA; single lab with multiple approaches\",\n      \"pmids\": [\"26700459\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"CPE stabilizes HYOU1 protein by inhibiting ubiquitin-proteasome degradation; CPE deficiency causes reduced HYOU1 protein levels. In osteosarcoma cells, CPE activates Hippo-YAP signaling and promotes YAP nuclear translocation. Overexpression of HYOU1 rescues the anti-tumor and pro-PANoptosis effects of CPE knockdown, placing HYOU1 downstream of CPE in this pathway.\",\n      \"method\": \"CPE knockdown/knockout, HYOU1 overexpression rescue, proteasome inhibitor treatment, Western blot for ubiquitination and YAP pathway, xenograft tumor model, immunofluorescence for YAP localization\",\n      \"journal\": \"Cancer letters\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — CPE-HYOU1 epistasis suggested by rescue experiment but ubiquitination mechanism not directly shown for HYOU1; single lab, limited mechanistic depth for HYOU1 specifically\",\n      \"pmids\": [\"41213463\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"HYOU1/ORP150/GRP170 is an ER-resident large Hsp70 (Hsp110 family) that functions both as a holdase chaperone—binding unfolded or misfolded secretory proteins via two distinct substrate-binding domains (a β-sandwich domain and a unique C-terminal α-helical domain) in an ATP-independent manner—and as a nucleotide exchange factor (NEF) for the canonical ER Hsp70, BiP, converting ADP-BiP to ATP-BiP to release substrates for retrotranslocation during ERAD; GRP170 is physically anchored near the retrotranslocon by binding Sel1L, thereby coupling substrate release from BiP with retrotranslocation through the Hrd1-Sel1L complex. Beyond quality control, GRP170 is required for the folding and forward trafficking of specific clients including VEGF, TSH receptor, and ENaC, and regulates ER calcium homeostasis; its loss disrupts ER proteostasis, activates the UPR, and is lethal at the cellular and organismal level.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"HYOU1 (ORP150/GRP170) is an ER-resident member of the HSP70 superfamily that functions as a stress-inducible molecular chaperone safeguarding secretory protein folding and ER proteostasis [#1, #10]. Originally isolated as a ~150 kDa hypoxia-induced ER stress protein in astrocytes, it is transcriptionally upregulated by oxygen deprivation and its loss accelerates hypoxia-specific apoptosis, defining a cytoprotective role under ER stress [#0, #3]. Biochemically it acts as an ATP-independent holdase: it binds unfolded—but not folded—secretory substrates and maintains denatured proteins in a soluble, refolding-competent state through two distinct substrate-binding regions, a β-sandwich peptide-binding domain and a unique C-terminal α-helical/hook domain, the latter not found in conventional Hsp70s [#10, #16]. In parallel it serves as a nucleotide exchange factor for the canonical ER Hsp70 BiP, catalyzing ADP→ATP exchange to release clients [#12, #18]; in ER-associated degradation it converts ADP-BiP to ATP-BiP to disengage misfolded substrates such as NHK α1-antitrypsin and physically binds the Hrd1 adaptor Sel1L, coupling client release from BiP to retrotranslocation through the Hrd1-Sel1L complex [#18, #19]. This dual activity makes GRP170 essential for BiP function and ER homeostasis: its loss in fibroblasts causes BiP and aggregation-prone clients to become insoluble, activates the UPR, and is lethal [#27]. Beyond quality control, GRP170 chaperones specific secretory clients, promoting VEGF secretion [#7] and the conformational maturation and surface trafficking of the ENaC channel and the TSH receptor, with tissue-specific knockout producing renal ion-homeostasis failure and primary hypothyroidism respectively [#17, #24, #28]. It also regulates ER calcium homeostasis in neurons, limiting calpain/cathepsin activation and excitotoxic death [#8]. Extracellularly, GRP170's chaperoning domain mediates receptor-bound (SR-A, SREC-I) uptake by antigen-presenting cells and cross-presentation, underlying its immunoadjuvant activity [#13, #14].\",\n  \"teleology\": [\n    {\n      \"year\": 1996,\n      \"claim\": \"Established the existence of a previously unknown ER stress protein selectively induced by hypoxia, defining HYOU1 as an oxygen-deprivation-responsive ER component distinct from heat-shock and other stress responses.\",\n      \"evidence\": \"Protein purification, N-terminal sequencing, subcellular fractionation and nuclear run-off in astrocytes\",\n      \"pmids\": [\"8617779\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular function unknown at this stage\", \"No substrate or partner identified\", \"Sequence/domain identity not yet determined\"]\n    },\n    {\n      \"year\": 1997,\n      \"claim\": \"Resolved the molecular identity of the protein by cloning the cDNA, revealing an ER-targeted HSP70-superfamily member with an ATPase-like domain and ER retention signal.\",\n      \"evidence\": \"cDNA cloning and deduced sequence/domain analysis\",\n      \"pmids\": [\"9020069\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Chaperone activity not functionally demonstrated\", \"ATPase activity not biochemically tested\", \"Client proteins unknown\"]\n    },\n    {\n      \"year\": 1999,\n      \"claim\": \"Demonstrated that HYOU1 is a peptide-binding ER chaperone and that its loss specifically sensitizes cells to hypoxic death, linking biochemical substrate binding to a cytoprotective function.\",\n      \"evidence\": \"TAP-mediated microsomal peptide-binding assay; stable antisense knockdown with viability/apoptosis readouts\",\n      \"pmids\": [\"10441153\", \"10037731\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Substrate selectivity defined only by comparison to a few ER chaperones\", \"Mechanism of cytoprotection not at molecular resolution\", \"ATP-dependence of binding not yet clarified\"]\n    },\n    {\n      \"year\": 2000,\n      \"claim\": \"Identified a physiological folding client and probed ATP regulation, showing HYOU1 binds the secretory glycoprotein GP80/clusterin and binds/hydrolyzes ATP, with substrate release at low ATP.\",\n      \"evidence\": \"Co-IP, pulse-chase maturation assay, ATP-agarose binding and ATP hydrolysis assay in MDCK cells\",\n      \"pmids\": [\"10837345\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Relationship between ATP hydrolysis and holdase activity left ambiguous\", \"Single client characterized\", \"No structural basis for ATP handling\"]\n    },\n    {\n      \"year\": 2001,\n      \"claim\": \"Established HYOU1 as a physiologically protective chaperone in vivo, controlling secretion of the angiogenic client VEGF and limiting ischemic/excitotoxic neuronal death via calcium and caspase regulation.\",\n      \"evidence\": \"Transgenic/heterozygous-KO mice, adenoviral delivery, stroke and wound-healing models, calcium and calpain/cathepsin assays\",\n      \"pmids\": [\"11231630\", \"11435456\", \"11714735\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct molecular link between HYOU1 and calcium handling not defined\", \"Whether VEGF binding is direct chaperone-client engagement not shown\", \"Mechanism connecting chaperone activity to caspase suppression unclear\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Described a non-canonical cytoplasmic isoform lacking the signal peptide that participates in NLS-dependent nuclear import, expanding HYOU1 functions beyond the ER lumen.\",\n      \"evidence\": \"Lectin affinity purification, NLS-dependent import assay, carbohydrate epitope analysis\",\n      \"pmids\": [\"11960996\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of nuclear import role undefined\", \"Cytoplasmic isoform abundance/relevance in vivo unclear\", \"Single-lab observation\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Reconstituted chaperone activity in vitro and mapped two substrate-binding regions, establishing HYOU1 as an ATP-independent holdase with a unique C-terminal α-helical substrate-binding feature.\",\n      \"evidence\": \"Recombinant protein, luciferase aggregation-suppression and refolding assays, domain-deletion mutagenesis\",\n      \"pmids\": [\"14674765\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of the α-helical domain not resolved\", \"Refolding required lysate factors—co-chaperone dependence undefined\", \"Physiological substrate spectrum not addressed\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Defined a second core biochemical activity by showing HYOU1 acts as a nucleotide exchange factor for BiP, positioning it within the ER Hsp70 cycle alongside Sil1.\",\n      \"evidence\": \"Biochemical nucleotide exchange assay and functional complementation\",\n      \"pmids\": [\"16962589\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How NEF and holdase activities are coordinated unresolved\", \"In-cell consequences of NEF activity not yet demonstrated\", \"No structural model of GRP170-BiP engagement\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Explained HYOU1's immunoadjuvant property mechanistically, showing its chaperoning domain mediates receptor-dependent (SR-A, SREC-I) uptake by APCs and cross-presentation to CD8+ T cells.\",\n      \"evidence\": \"Domain-deletion mutants, saturable receptor binding on receptor-expressing cells, competitive inhibition, T-cell IFN-γ readout\",\n      \"pmids\": [\"16424054\", \"17615582\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Endogenous extracellular GRP170 role unclear\", \"Physiological versus immunotherapeutic relevance not separated\", \"Structural determinants of receptor binding undefined\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Distinguished HYOU1 from BiP at the substrate level and defined intramolecular regulation, showing it binds only unfolded clients, remains bound in ATP, and that its α-helical domain promotes while an unstructured loop suppresses binding; also linked GRP170 holdase activity to ENaC ERAD.\",\n      \"evidence\": \"Co-IP with folded/unfolded substrates, ATP-release assay, domain-deletion mutants; yeast Lhs1 ENaC ERAD system with NEF vs holdase mutants and mammalian GRP170-αENaC Co-IP\",\n      \"pmids\": [\"24327659\", \"23645669\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Which clients depend on holdase vs NEF activity not generalized\", \"Structural mechanism of the regulatory loop unknown\", \"Selectivity for unglycosylated ENaC form mechanistically unexplained\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Integrated NEF activity into the ERAD pathway, showing GRP170 converts ADP-BiP to ATP-BiP to release misfolded clients and binds Sel1L to couple substrate disengagement with retrotranslocation through Hrd1-Sel1L.\",\n      \"evidence\": \"siRNA/overexpression, Grp170-Sel1L Co-IP, retrotranslocation and NHK/TTR ERAD assays\",\n      \"pmids\": [\"25877869\", \"27030672\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Stoichiometry and spatial organization of GRP170-BiP-Sel1L not resolved\", \"How holdase and NEF roles partition across glycosylated vs non-glycosylated clients unclear\", \"In vivo requirement not yet established\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Demonstrated that GRP170 is essential for BiP function and ER homeostasis at the whole-cell level, with its loss causing BiP and client insolubility, impaired client turnover, UPR activation, and death.\",\n      \"evidence\": \"Inducible conditional Grp170 knockout in MEFs, fractionation, BiP-client Co-IP, degradation and UPR/cell-death assays\",\n      \"pmids\": [\"38446639\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Which essential clients drive lethality unresolved\", \"Separation of NEF vs holdase contributions to essentiality not achieved\", \"Tissue-level consequences addressed separately\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Tied GRP170's chaperone function to tissue-specific physiology, showing it is required for ENaC-dependent renal ion homeostasis and for TSH-receptor maturation and trafficking, with knockouts causing kidney injury and primary hypothyroidism.\",\n      \"evidence\": \"Nephron- and thyrocyte-specific inducible knockout mice with in vitro trafficking/maturation assays\",\n      \"pmids\": [\"35104250\", \"40923318\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct chaperone engagement of TSHR/ENaC not shown structurally\", \"Whether NEF or holdase activity is rate-limiting in vivo unclear\", \"Full client repertoire across tissues unknown\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Provided the first structural view of the GRP170-ATP-BiP complex, revealing a C-terminal curved hook domain and a structural basis for pseudo-ATPase chaperone activity.\",\n      \"evidence\": \"2.7 Å cryo-EM of complex purified from HEK293 cells (preprint)\",\n      \"pmids\": [\"bio_10.1101_2025.10.25.684324\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Preprint, not peer-reviewed\", \"Hook-domain substrate engagement proposed but not functionally validated\", \"Conformational dynamics of nucleotide exchange not resolved\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How GRP170 mechanistically partitions its holdase versus NEF activities across individual clients, and how the curved hook domain physically engages substrate during the BiP nucleotide cycle, remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No functional confirmation of the hook-domain substrate model\", \"No comprehensive client repertoire mapping activity requirements\", \"Coordination between substrate release and retrotranslocon engagement not structurally defined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0044183\", \"supporting_discovery_ids\": [10, 16, 4]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [12, 18, 19]},\n      {\"term_id\": \"GO:0140657\", \"supporting_discovery_ids\": [4]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [16, 17]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005783\", \"supporting_discovery_ids\": [0, 1, 10, 16]},\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [15]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-392499\", \"supporting_discovery_ids\": [16, 18, 19, 27]},\n      {\"term_id\": \"R-HSA-8953897\", \"supporting_discovery_ids\": [0, 3, 27]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [13, 14]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"HSPA5\", \"SEL1L\", \"BACE1\", \"ENaC\", \"TSHR\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":8,"faith_total":8,"faith_pct":100.0}}