{"gene":"PDIA2","run_date":"2026-06-10T05:19:53","timeline":{"discoveries":[{"year":1996,"finding":"PDIA2 (PDIp) was isolated from human pancreas, characterized as a new PDI family member with two thioredoxin-like active sites (WCGHCQ and WCTHCK) and an ER retention signal (KEEL). Recombinant PDIp catalyzed reductive cleavage of insulin and renaturation of reduced RNaseA, confirming enzymatic protein disulfide isomerase activity.","method":"Recombinant protein expression and in vitro enzymatic assays (insulin reductive cleavage, RNaseA renaturation)","journal":"DNA and cell biology","confidence":"High","confidence_rationale":"Tier 1 / Strong — direct in vitro reconstitution of enzymatic activity with multiple substrates, replicated in subsequent studies","pmids":["8561901"],"is_preprint":false},{"year":1997,"finding":"PDIA2 (PDIp) is a glycoprotein expressed specifically in pancreatic acinar cells. Western blot with peptide:N-glycosidase F treatment confirmed glycosylation. The protein is conserved between human and mouse pancreas.","method":"Western blot, immunohistochemistry, peptide:N-glycosidase F treatment, cross-species protein detection","journal":"DNA and cell biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — enzymatic deglycosylation plus IHC localization, single lab","pmids":["9115635"],"is_preprint":false},{"year":1997,"finding":"Canine PDIA2 (PDIp) is in transient contact with secretory proteins during late stages of co- and posttranslational translocation into pancreas microsomes, sharing this polypeptide-binding/chaperoning activity with PDI. Its concentration in pancreatic microsomes approaches that of PDI and major microsomal molecular chaperones.","method":"Cross-linking and identification in dog pancreas microsomes during translocation assays","journal":"FEBS letters","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — cross-linking in microsomes with functional context, single lab","pmids":["9136904"],"is_preprint":false},{"year":2000,"finding":"Tyrosine and tryptophan residues in peptides are the recognition motifs for binding to PDIA2 (PDIp). PDIp specifically interacts with radiolabeled peptides and misfolded proteins in vitro via these aromatic residues.","method":"Cross-linking approach with radiolabeled peptides and peptide variants in crude pancreas microsome extracts","journal":"Protein science","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — cross-linking with systematic peptide variants, single lab","pmids":["10794419"],"is_preprint":false},{"year":2001,"finding":"A hydroxyaryl group is a structural recognition motif for ligand binding to PDIA2 (PDIp). Simple hydroxyaryl-containing constructs, xenobiotics, and phytoestrogens containing an unmodified hydroxyaryl group efficiently inhibit peptide binding to PDIp.","method":"Cross-linking competition assay with non-peptide ligands and structural variants","journal":"The Biochemical journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — cross-linking inhibition with diverse chemical structures, single lab","pmids":["11237859"],"is_preprint":false},{"year":2009,"finding":"Human PDIA2 (PDIp) binds 17β-estradiol (E2) with an apparent Kd of ~1.5 µM. Among six PDI homologs tested, only PDIp and PDI showed similar E2 binding affinity, but with distinct preferences for estrogen analogs. PDIp can serve as a high-capacity intracellular E2-binding protein, modulating intracellular E2 concentrations in cultured cells and human pancreatic tissue; PDIp-bound E2 can be released upon a drop in extracellular E2, augmenting estrogen receptor-mediated transcription.","method":"Radiolabeled 17β-estradiol binding assay, competition binding with analogs, cell-based E2 concentration measurement","journal":"The Journal of steroid biochemistry and molecular biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — radioligand binding assay plus cell-based functional readout, single lab","pmids":["19429457"],"is_preprint":false},{"year":2009,"finding":"PDIA2 (PDIp) forms an inter-subunit disulfide bond (primarily through a non-active-site cysteine-4, unique to human and primate PDIp) under oxidizing conditions, which alters its structure (exposes hydrophobic patches, increases protease sensitivity) and enhances its chaperone activity. The protein exists predominantly as a monomer under reducing conditions.","method":"Redox-dependent dimerization assay, protease sensitivity assay, chaperone activity assay under reducing vs. oxidizing conditions, mutagenesis of cysteine residues","journal":"Archives of biochemistry and biophysics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — mutagenesis plus multiple functional assays, single lab","pmids":["19150607"],"is_preprint":false},{"year":2010,"finding":"The chaperone activity of PDIA2 (PDIp) is independent of its enzymatic (isomerase) activity. Alkylation of active-site cysteines abolishes enzymatic activity but preserves chaperone activity. Mutation of active-site cysteine residues confirms this independence. The b-b' fragment (lacking active sites) retains chaperone activity. PDIp forms stable, stoichiometric complexes with denatured substrate proteins (e.g., GAPDH) that can later dissociate. Expression in E. coli confers protection against heat shock and oxidative stress independently of enzymatic activity.","method":"Iodoacetamide alkylation, active-site mutagenesis, fragment expression, in vitro aggregation prevention assay, E. coli stress-protection assay","journal":"The Biochemical journal","confidence":"High","confidence_rationale":"Tier 1 / Strong — multiple orthogonal methods (mutagenesis, chemical inhibition, fragment analysis, in vivo functional assay) in one study","pmids":["20423326"],"is_preprint":false},{"year":2011,"finding":"Both PDIA2 (PDIp) and PDI can attack native disulfide bonds in thermally-unfolded RNase and form stable disulfide-linked complexes via thiol-disulfide exchange. The N-terminal active site of PDIp is essential for this inactivation of RNase. RNase in the complexes can be released and reactivated in a redox-dependent manner.","method":"Thermal unfolding assay, co-incubation with PDI/PDIp, alkylation controls, active-site mutagenesis","journal":"Biochimica et biophysica acta","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — in vitro mechanistic assay with mutagenesis, single lab","pmids":["21238616"],"is_preprint":false},{"year":2012,"finding":"All three predicted N-linked glycosylation sites of human PDIA2 (N127, N284, N516) are glycosylated in human cells. Mutation of N284 to Gln increases formation of a highly stable disulfide-bonded PDIA2 dimer, indicating that N284 glycosylation modulates protein-protein interactions. Both wild-type and N127/284/516Q mutant PDIA2 localize to the ER (but not ERGIC), showing glycosylation does not affect ER localization. PDIA2 was identified as binding to HLA-A,B,C (MHC class I) antigens.","method":"Site-directed mutagenesis, enzymatic deglycosylation, subcellular localization imaging in HeLa cells, co-immunoprecipitation/pulldown for MHC class I interaction","journal":"The FEBS journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — mutagenesis plus localization and interaction data, single lab","pmids":["23167757"],"is_preprint":false},{"year":2012,"finding":"Endogenous PDIA2 (PDIp) purified from rat and human pancreatic tissues binds E2 with a Kd of ~150 nM. PDIp-bound E2 accounts for over 80% of total protein-bound E2 in rat and human pancreatic tissue. This binding protects E2 from metabolic disposition. In ovariectomized rats, pancreatic E2 levels remain elevated for up to 96 h after a single E2 injection, consistent with PDIp acting as an intracellular E2 reservoir.","method":"Purification of endogenous PDIp from pancreatic tissue, radioligand binding assay, in vivo ovariectomized rat model with E2 tissue quantification","journal":"The Biochemical journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — endogenous protein purification, quantitative binding, in vivo model, single lab","pmids":["22747530"],"is_preprint":false},{"year":2013,"finding":"Computational homology modeling of the PDIA2 (PDIp) b-b' domain identified His278 as critical for estradiol binding via a hydrogen bond with the 3-hydroxyl group. This was experimentally confirmed by selective mutations of predicted binding-site residues and selective modifications of ligand functional groups.","method":"Homology modeling, docking, site-directed mutagenesis of binding-site residues, ligand functional group modification","journal":"Current medicinal chemistry","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — mutagenesis confirming computational prediction, single lab","pmids":["23931275"],"is_preprint":false},{"year":2018,"finding":"PDIA2 (PDIp) physically interacts with multiple pancreatic digestive enzymes in vivo (identified by MS after acid quenching and thiol alkylation to stabilize transient disulfide-linked complexes). PDIp prevents aggregation of proelastase in cultured cells when co-expressed, and enhances secretion of properly folded proelastase that can be activated by trypsin, establishing digestive enzymes as physiological substrates.","method":"Acid quenching/thiol alkylation to trap complexes, MS identification of endogenous substrates from mouse pancreas, co-expression experiments in cultured cells","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vivo substrate trapping with MS plus cell-based reconstitution with functional readout, multiple orthogonal methods","pmids":["30315102"],"is_preprint":false},{"year":2022,"finding":"PDIA2 translocates from the ER to mitochondria under AOM/DSS-induced ER stress conditions in colon cancer, where it interacts with components of mitochondrial complexes I and II to inhibit oxidative phosphorylation and increase glycolysis. Knockdown of PDIA2 in colon cancer cells restores the metabolic balance and suppresses xenograft tumor growth.","method":"Co-immunoprecipitation (PDIA2 with complex I/II components), subcellular fractionation/localization, metabolic assays (oxygen flux, extracellular acidification, targeted metabolomics), xenograft model with PDIA2 knockdown","journal":"Frontiers in oncology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP plus metabolic assays plus in vivo knockdown, single lab","pmids":["35860571"],"is_preprint":false},{"year":2024,"finding":"PDIA2 activates tissue factor (TF) on tumor-derived extracellular vesicles (EVs) through its isomerase activity, triggering a pro-thrombotic cascade. TF-containing EVs also activate Src kinase inside PCa cells to enhance androgen receptor (AR) signaling ligand-independently. Androgen deprivation suppresses clathrin-dependent endocytosis, enhancing PDIA2 translocation to the cell membrane and EVs. Co-recruitment of AR and FOXA1 to the PDIA2 promoter is required for PDIA2 transcription under androgen-deprived conditions. Blocking PDIA2 isomerase activity suppresses pro-coagulation activity and castrate-resistant tumor growth.","method":"In vitro and in vivo models, EV isolation and characterization, TF activity assay, isomerase inhibition experiments, Src kinase activation assay, chromatin immunoprecipitation (AR/FOXA1 at PDIA2 promoter), xenograft models","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple in vitro and in vivo methods, single lab, mechanistic pathway established","pmids":["38589675"],"is_preprint":false}],"current_model":"PDIA2 (PDIp) is a pancreas-enriched ER-resident protein disulfide isomerase that catalyzes thiol-disulfide exchange reactions to assist folding of secretory proteins (especially pancreatic digestive enzymes), acts as a molecular chaperone independently of its enzymatic activity by forming stable complexes with denatured substrates, binds and sequesters estradiol in pancreatic tissue, is regulated by redox-dependent inter-subunit disulfide bond formation (via Cys-4), and under stress conditions can translocate to mitochondria or the cell surface/EVs where its isomerase activity activates tissue factor to promote pro-thrombotic and pro-tumorigenic signaling."},"narrative":{"mechanistic_narrative":"PDIA2 (PDIp) is a pancreas-enriched, ER-resident protein disulfide isomerase that catalyzes thiol-disulfide exchange to assist folding of secretory proteins, particularly pancreatic digestive enzymes [PMID:8561901, PMID:30315102]. It carries two thioredoxin-like active sites and an ER retention signal, and reconstituted recombinant protein catalyzes reductive cleavage of insulin and renaturation of reduced RNaseA [PMID:8561901]. Beyond its catalytic role, PDIA2 acts as a molecular chaperone independently of its isomerase activity: alkylation or mutation of active-site cysteines abolishes enzymatic function while preserving the ability to form stable, stoichiometric complexes with denatured substrates and to prevent aggregation, an activity retained by the active-site-free b-b' fragment [PMID:20423326]. It recognizes substrates through exposed aromatic (tyrosine/tryptophan) and hydroxyaryl motifs [PMID:10794419, PMID:11237859], and in vivo it physically engages multiple pancreatic digestive enzymes, preventing proelastase aggregation and enhancing secretion of activatable, properly folded enzyme [PMID:30315102]. PDIA2 is a glycoprotein whose N-glycosylation (notably at N284) modulates inter-subunit disulfide-bonded dimer formation, and a non-active-site Cys-4 mediates redox-dependent dimerization that exposes hydrophobic patches and enhances chaperone activity under oxidizing conditions [PMID:19150607, PMID:23167757]. The hydroxyaryl-binding b-b' domain also binds 17β-estradiol via His278, allowing PDIp to act as a high-capacity intracellular estradiol reservoir in pancreatic tissue that protects bound E2 from metabolic disposition [PMID:19429457, PMID:22747530, PMID:23931275]. Under stress, PDIA2 acquires non-canonical localizations and functions: it translocates from the ER to mitochondria in colon cancer to interact with complex I/II components, inhibiting oxidative phosphorylation and promoting glycolysis and tumor growth [PMID:35860571], and it is exported to the cell surface and extracellular vesicles where its isomerase activity activates tissue factor to drive pro-thrombotic signaling and ligand-independent androgen receptor activation via Src in prostate cancer [PMID:38589675].","teleology":[{"year":1996,"claim":"Established that PDIA2 is a bona fide protein disulfide isomerase, defining its core catalytic identity through its two thioredoxin-like active sites and demonstrated thiol-disulfide exchange activity.","evidence":"Recombinant protein expression with in vitro insulin reductive cleavage and RNaseA renaturation assays","pmids":["8561901"],"confidence":"High","gaps":["Did not identify physiological substrates","Tissue-specific expression context not yet defined"]},{"year":1997,"claim":"Located PDIA2 expression to pancreatic acinar cells as a glycoprotein and showed conservation across species, establishing it as a tissue-restricted secretory-pathway PDI.","evidence":"Western blot with PNGase F deglycosylation, immunohistochemistry, and cross-species detection; cross-linking in dog pancreas microsomes during translocation","pmids":["9115635","9136904"],"confidence":"Medium","gaps":["Functional role of glycosylation unresolved","Specific secretory substrates not identified"]},{"year":2001,"claim":"Defined the molecular recognition code for PDIA2 substrate binding, showing that aromatic and hydroxyaryl groups serve as docking motifs and rationalizing later ligand-binding behavior.","evidence":"Cross-linking with radiolabeled peptide variants and competition with non-peptide hydroxyaryl ligands in pancreas microsome extracts","pmids":["10794419","11237859"],"confidence":"Medium","gaps":["Did not establish which native proteins these motifs map to","Binding-site residues not yet mapped"]},{"year":2010,"claim":"Separated PDIA2's chaperone function from its enzymatic activity, demonstrating that aggregation prevention and stress protection persist when active-site cysteines are abolished.","evidence":"Iodoacetamide alkylation, active-site mutagenesis, b-b' fragment expression, in vitro aggregation assays, and E. coli stress-protection assay","pmids":["20423326"],"confidence":"High","gaps":["In-cell relevance of enzyme-independent chaperoning not directly tested","Substrate spectrum for chaperone mode undefined"]},{"year":2012,"claim":"Showed that redox state and N-glycosylation regulate PDIA2 quaternary structure, linking Cys-4 dimerization and N284 glycosylation to modulation of chaperone activity and protein interactions.","evidence":"Redox-dependent dimerization, protease sensitivity and chaperone assays with cysteine mutagenesis; site-directed glycosylation mutants with localization and MHC class I pulldown","pmids":["19150607","23167757"],"confidence":"Medium","gaps":["Physiological trigger for dimerization in pancreas not defined","Functional significance of MHC class I interaction not pursued"]},{"year":2013,"claim":"Characterized PDIA2 as a high-capacity intracellular estradiol-binding protein, identifying His278 in the b-b' domain as the binding determinant and establishing a reservoir role in pancreatic tissue.","evidence":"Radioligand E2 binding assays, endogenous protein purification, in vivo ovariectomized rat model, and homology modeling with binding-site mutagenesis","pmids":["19429457","22747530","23931275"],"confidence":"Medium","gaps":["Physiological consequence of pancreatic E2 sequestration on signaling not fully resolved","Single-lab assays"]},{"year":2018,"claim":"Identified pancreatic digestive enzymes as physiological PDIA2 substrates in vivo, confirming its predicted role in folding and secretion of secretory cargo.","evidence":"Acid-quench/thiol-alkylation substrate trapping with MS from mouse pancreas plus co-expression rescue of proelastase folding and secretion","pmids":["30315102"],"confidence":"High","gaps":["Full substrate repertoire not exhaustively defined","In vivo loss-of-function consequences in pancreas not assessed"]},{"year":2024,"claim":"Revealed non-ER, disease-associated functions of PDIA2, where stress-induced relocalization to mitochondria or to extracellular vesicles reprograms metabolism and activates tissue factor / AR signaling to drive tumor progression.","evidence":"Co-IP with mitochondrial complex I/II, metabolic and xenograft assays in colon cancer; EV isolation, TF activity and isomerase inhibition, Src activation, and AR/FOXA1 ChIP at the PDIA2 promoter in prostate cancer","pmids":["35860571","38589675"],"confidence":"Medium","gaps":["Mechanism of ER-to-mitochondria translocation not defined","Single-lab reports for each non-canonical function","Direct structural confirmation of TF activation by PDIA2 isomerase lacking"]},{"year":null,"claim":"How PDIA2 is trafficked out of the ER to mitochondria, plasma membrane, and EVs under stress, and whether its pancreatic folding role and its tumor-associated moonlighting functions are mechanistically connected, remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structure of full-length PDIA2 or its substrate complexes","Trafficking determinants for non-ER localization unknown","Loss-of-function pancreatic phenotype uncharacterized"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016853","term_label":"isomerase activity","supporting_discovery_ids":[0,8,14]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[0,12]},{"term_id":"GO:0044183","term_label":"protein folding chaperone","supporting_discovery_ids":[7,12]},{"term_id":"GO:0140313","term_label":"molecular sequestering activity","supporting_discovery_ids":[5,10]},{"term_id":"GO:0008289","term_label":"lipid binding","supporting_discovery_ids":[5,10,11]}],"localization":[{"term_id":"GO:0005783","term_label":"endoplasmic reticulum","supporting_discovery_ids":[0,2,9]},{"term_id":"GO:0005739","term_label":"mitochondrion","supporting_discovery_ids":[13]},{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[14]}],"pathway":[{"term_id":"R-HSA-392499","term_label":"Metabolism of proteins","supporting_discovery_ids":[0,7,12]},{"term_id":"R-HSA-1643685","term_label":"Disease","supporting_discovery_ids":[13,14]}],"complexes":[],"partners":["TF","AR","FOXA1"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q13087","full_name":"Protein disulfide-isomerase A2","aliases":["Pancreas-specific protein disulfide isomerase","PDIp"],"length_aa":525,"mass_kda":58.2,"function":"Acts as an intracellular estrogen-binding protein. May be involved in modulating cellular levels and biological functions of estrogens in the pancreas. May act as a chaperone that inhibits aggregation of misfolded proteins","subcellular_location":"Endoplasmic reticulum lumen","url":"https://www.uniprot.org/uniprotkb/Q13087/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/PDIA2","classification":"Not Classified","n_dependent_lines":2,"n_total_lines":1208,"dependency_fraction":0.0016556291390728477},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/PDIA2","total_profiled":1310},"omim":[{"mim_id":"608012","title":"PROTEIN DISULFIDE ISOMERASE, FAMILY A, MEMBER 2; PDIA2","url":"https://www.omim.org/entry/608012"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Tissue enriched","tissue_distribution":"Detected in many","driving_tissues":[{"tissue":"pancreas","ntpm":2364.1}],"url":"https://www.proteinatlas.org/search/PDIA2"},"hgnc":{"alias_symbol":["PDA2","PDI","PDIR"],"prev_symbol":["PDIP"]},"alphafold":{"accession":"Q13087","domains":[{"cath_id":"3.40.30.10","chopping":"41-152","consensus_level":"high","plddt":94.0863,"start":41,"end":152},{"cath_id":"3.40.30.10","chopping":"157-256","consensus_level":"high","plddt":93.8108,"start":157,"end":256},{"cath_id":"3.40.30.10","chopping":"260-370","consensus_level":"high","plddt":93.6375,"start":260,"end":370},{"cath_id":"3.40.30.10","chopping":"392-494","consensus_level":"high","plddt":94.9968,"start":392,"end":494}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q13087","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q13087-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q13087-F1-predicted_aligned_error_v6.png","plddt_mean":86.69},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=PDIA2","jax_strain_url":"https://www.jax.org/strain/search?query=PDIA2"},"sequence":{"accession":"Q13087","fasta_url":"https://rest.uniprot.org/uniprotkb/Q13087.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q13087/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q13087"}},"corpus_meta":[{"pmid":"15353226","id":"PMC_15353226","title":"Identification of the protein disulfide isomerase family member PDIp in experimental Parkinson's disease and Lewy body pathology.","date":"2004","source":"Brain research","url":"https://pubmed.ncbi.nlm.nih.gov/15353226","citation_count":115,"is_preprint":false},{"pmid":"8561901","id":"PMC_8561901","title":"Characterization and chromosomal localization of a new protein disulfide isomerase, PDIp, highly expressed in human pancreas.","date":"1996","source":"DNA and cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/8561901","citation_count":64,"is_preprint":false},{"pmid":"9115635","id":"PMC_9115635","title":"Molecular characterization of a pancreas-specific protein disulfide isomerase, PDIp.","date":"1997","source":"DNA and cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/9115635","citation_count":44,"is_preprint":false},{"pmid":"10794419","id":"PMC_10794419","title":"Specificity in substrate binding by protein folding catalysts: tyrosine and tryptophan residues are the recognition motifs for the binding of peptides to the pancreas-specific protein disulfide isomerase PDIp.","date":"2000","source":"Protein science : a publication of the Protein Society","url":"https://pubmed.ncbi.nlm.nih.gov/10794419","citation_count":43,"is_preprint":false},{"pmid":"23782473","id":"PMC_23782473","title":"Clinicopathological features and CCT2 and PDIA2 expression in gallbladder squamous/adenosquamous carcinoma and gallbladder adenocarcinoma.","date":"2013","source":"World journal of surgical oncology","url":"https://pubmed.ncbi.nlm.nih.gov/23782473","citation_count":31,"is_preprint":false},{"pmid":"11237859","id":"PMC_11237859","title":"The pancreas-specific protein disulphide-isomerase PDIp interacts with a hydroxyaryl group in ligands.","date":"2001","source":"The Biochemical journal","url":"https://pubmed.ncbi.nlm.nih.gov/11237859","citation_count":27,"is_preprint":false},{"pmid":"19429457","id":"PMC_19429457","title":"Human pancreas-specific protein disulfide isomerase homolog (PDIp) is an intracellular estrogen-binding protein that modulates estrogen levels and actions in target cells.","date":"2009","source":"The Journal of steroid biochemistry and molecular biology","url":"https://pubmed.ncbi.nlm.nih.gov/19429457","citation_count":26,"is_preprint":false},{"pmid":"20423326","id":"PMC_20423326","title":"Human pancreas-specific protein disulfide-isomerase (PDIp) can function as a chaperone independently of its enzymatic activity by forming stable complexes with denatured substrate proteins.","date":"2010","source":"The Biochemical journal","url":"https://pubmed.ncbi.nlm.nih.gov/20423326","citation_count":26,"is_preprint":false},{"pmid":"9136904","id":"PMC_9136904","title":"Pancreas specific protein disulfide isomerase, PDIp, is in transient contact with secretory proteins during late stages of translocation.","date":"1997","source":"FEBS 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biophysics","url":"https://pubmed.ncbi.nlm.nih.gov/19150607","citation_count":14,"is_preprint":false},{"pmid":"30315102","id":"PMC_30315102","title":"Identification of the physiological substrates of PDIp, a pancreas-specific protein-disulfide isomerase family member.","date":"2018","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/30315102","citation_count":11,"is_preprint":false},{"pmid":"38589675","id":"PMC_38589675","title":"PDIA2 has a dual function in promoting androgen deprivation therapy induced venous thrombosis events and castrate resistant prostate cancer progression.","date":"2024","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/38589675","citation_count":4,"is_preprint":false},{"pmid":"33293489","id":"PMC_33293489","title":"Genetic Variants in Host Protein Disulfide Isomerase 2 (PDIA2) are Associated with Susceptibility to Chlamydia Trachomatis Infection.","date":"2020","source":"Journal of the Association of Genetic Technologists","url":"https://pubmed.ncbi.nlm.nih.gov/33293489","citation_count":3,"is_preprint":false},{"pmid":"23931275","id":"PMC_23931275","title":"Usefulness of molecular modeling in characterizing the ligand-binding sites of proteins: experience with human PDI, PDIp and COX.","date":"2013","source":"Current medicinal chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/23931275","citation_count":2,"is_preprint":false},{"pmid":"21238616","id":"PMC_21238616","title":"Both PDI and PDIp can attack the native disulfide bonds in thermally-unfolded RNase and form stable disulfide-linked complexes.","date":"2011","source":"Biochimica et biophysica acta","url":"https://pubmed.ncbi.nlm.nih.gov/21238616","citation_count":2,"is_preprint":false},{"pmid":"22747530","id":"PMC_22747530","title":"PDIp is a major intracellular oestrogen-storage protein that modulates tissue levels of oestrogen in the pancreas.","date":"2012","source":"The Biochemical 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Hck","date":"2024-11-08","source":"bioRxiv","url":"https://doi.org/10.1101/2024.11.05.622136","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":12156,"output_tokens":3863,"usd":0.047206,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":11585,"output_tokens":3372,"usd":0.071112,"stage2_stop_reason":"end_turn"},"total_usd":0.118318,"stage1_batch_id":"msgbatch_013a8chtv3AWyTqv4z4sEF4C","stage2_batch_id":"msgbatch_01AHsuW63vinsvuTgzmQ3n62","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1996,\n      \"finding\": \"PDIA2 (PDIp) was isolated from human pancreas, characterized as a new PDI family member with two thioredoxin-like active sites (WCGHCQ and WCTHCK) and an ER retention signal (KEEL). Recombinant PDIp catalyzed reductive cleavage of insulin and renaturation of reduced RNaseA, confirming enzymatic protein disulfide isomerase activity.\",\n      \"method\": \"Recombinant protein expression and in vitro enzymatic assays (insulin reductive cleavage, RNaseA renaturation)\",\n      \"journal\": \"DNA and cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — direct in vitro reconstitution of enzymatic activity with multiple substrates, replicated in subsequent studies\",\n      \"pmids\": [\"8561901\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1997,\n      \"finding\": \"PDIA2 (PDIp) is a glycoprotein expressed specifically in pancreatic acinar cells. Western blot with peptide:N-glycosidase F treatment confirmed glycosylation. The protein is conserved between human and mouse pancreas.\",\n      \"method\": \"Western blot, immunohistochemistry, peptide:N-glycosidase F treatment, cross-species protein detection\",\n      \"journal\": \"DNA and cell biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — enzymatic deglycosylation plus IHC localization, single lab\",\n      \"pmids\": [\"9115635\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1997,\n      \"finding\": \"Canine PDIA2 (PDIp) is in transient contact with secretory proteins during late stages of co- and posttranslational translocation into pancreas microsomes, sharing this polypeptide-binding/chaperoning activity with PDI. Its concentration in pancreatic microsomes approaches that of PDI and major microsomal molecular chaperones.\",\n      \"method\": \"Cross-linking and identification in dog pancreas microsomes during translocation assays\",\n      \"journal\": \"FEBS letters\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — cross-linking in microsomes with functional context, single lab\",\n      \"pmids\": [\"9136904\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"Tyrosine and tryptophan residues in peptides are the recognition motifs for binding to PDIA2 (PDIp). PDIp specifically interacts with radiolabeled peptides and misfolded proteins in vitro via these aromatic residues.\",\n      \"method\": \"Cross-linking approach with radiolabeled peptides and peptide variants in crude pancreas microsome extracts\",\n      \"journal\": \"Protein science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — cross-linking with systematic peptide variants, single lab\",\n      \"pmids\": [\"10794419\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"A hydroxyaryl group is a structural recognition motif for ligand binding to PDIA2 (PDIp). Simple hydroxyaryl-containing constructs, xenobiotics, and phytoestrogens containing an unmodified hydroxyaryl group efficiently inhibit peptide binding to PDIp.\",\n      \"method\": \"Cross-linking competition assay with non-peptide ligands and structural variants\",\n      \"journal\": \"The Biochemical journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — cross-linking inhibition with diverse chemical structures, single lab\",\n      \"pmids\": [\"11237859\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"Human PDIA2 (PDIp) binds 17β-estradiol (E2) with an apparent Kd of ~1.5 µM. Among six PDI homologs tested, only PDIp and PDI showed similar E2 binding affinity, but with distinct preferences for estrogen analogs. PDIp can serve as a high-capacity intracellular E2-binding protein, modulating intracellular E2 concentrations in cultured cells and human pancreatic tissue; PDIp-bound E2 can be released upon a drop in extracellular E2, augmenting estrogen receptor-mediated transcription.\",\n      \"method\": \"Radiolabeled 17β-estradiol binding assay, competition binding with analogs, cell-based E2 concentration measurement\",\n      \"journal\": \"The Journal of steroid biochemistry and molecular biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — radioligand binding assay plus cell-based functional readout, single lab\",\n      \"pmids\": [\"19429457\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"PDIA2 (PDIp) forms an inter-subunit disulfide bond (primarily through a non-active-site cysteine-4, unique to human and primate PDIp) under oxidizing conditions, which alters its structure (exposes hydrophobic patches, increases protease sensitivity) and enhances its chaperone activity. The protein exists predominantly as a monomer under reducing conditions.\",\n      \"method\": \"Redox-dependent dimerization assay, protease sensitivity assay, chaperone activity assay under reducing vs. oxidizing conditions, mutagenesis of cysteine residues\",\n      \"journal\": \"Archives of biochemistry and biophysics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — mutagenesis plus multiple functional assays, single lab\",\n      \"pmids\": [\"19150607\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"The chaperone activity of PDIA2 (PDIp) is independent of its enzymatic (isomerase) activity. Alkylation of active-site cysteines abolishes enzymatic activity but preserves chaperone activity. Mutation of active-site cysteine residues confirms this independence. The b-b' fragment (lacking active sites) retains chaperone activity. PDIp forms stable, stoichiometric complexes with denatured substrate proteins (e.g., GAPDH) that can later dissociate. Expression in E. coli confers protection against heat shock and oxidative stress independently of enzymatic activity.\",\n      \"method\": \"Iodoacetamide alkylation, active-site mutagenesis, fragment expression, in vitro aggregation prevention assay, E. coli stress-protection assay\",\n      \"journal\": \"The Biochemical journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — multiple orthogonal methods (mutagenesis, chemical inhibition, fragment analysis, in vivo functional assay) in one study\",\n      \"pmids\": [\"20423326\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Both PDIA2 (PDIp) and PDI can attack native disulfide bonds in thermally-unfolded RNase and form stable disulfide-linked complexes via thiol-disulfide exchange. The N-terminal active site of PDIp is essential for this inactivation of RNase. RNase in the complexes can be released and reactivated in a redox-dependent manner.\",\n      \"method\": \"Thermal unfolding assay, co-incubation with PDI/PDIp, alkylation controls, active-site mutagenesis\",\n      \"journal\": \"Biochimica et biophysica acta\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro mechanistic assay with mutagenesis, single lab\",\n      \"pmids\": [\"21238616\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"All three predicted N-linked glycosylation sites of human PDIA2 (N127, N284, N516) are glycosylated in human cells. Mutation of N284 to Gln increases formation of a highly stable disulfide-bonded PDIA2 dimer, indicating that N284 glycosylation modulates protein-protein interactions. Both wild-type and N127/284/516Q mutant PDIA2 localize to the ER (but not ERGIC), showing glycosylation does not affect ER localization. PDIA2 was identified as binding to HLA-A,B,C (MHC class I) antigens.\",\n      \"method\": \"Site-directed mutagenesis, enzymatic deglycosylation, subcellular localization imaging in HeLa cells, co-immunoprecipitation/pulldown for MHC class I interaction\",\n      \"journal\": \"The FEBS journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — mutagenesis plus localization and interaction data, single lab\",\n      \"pmids\": [\"23167757\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Endogenous PDIA2 (PDIp) purified from rat and human pancreatic tissues binds E2 with a Kd of ~150 nM. PDIp-bound E2 accounts for over 80% of total protein-bound E2 in rat and human pancreatic tissue. This binding protects E2 from metabolic disposition. In ovariectomized rats, pancreatic E2 levels remain elevated for up to 96 h after a single E2 injection, consistent with PDIp acting as an intracellular E2 reservoir.\",\n      \"method\": \"Purification of endogenous PDIp from pancreatic tissue, radioligand binding assay, in vivo ovariectomized rat model with E2 tissue quantification\",\n      \"journal\": \"The Biochemical journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — endogenous protein purification, quantitative binding, in vivo model, single lab\",\n      \"pmids\": [\"22747530\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Computational homology modeling of the PDIA2 (PDIp) b-b' domain identified His278 as critical for estradiol binding via a hydrogen bond with the 3-hydroxyl group. This was experimentally confirmed by selective mutations of predicted binding-site residues and selective modifications of ligand functional groups.\",\n      \"method\": \"Homology modeling, docking, site-directed mutagenesis of binding-site residues, ligand functional group modification\",\n      \"journal\": \"Current medicinal chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — mutagenesis confirming computational prediction, single lab\",\n      \"pmids\": [\"23931275\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"PDIA2 (PDIp) physically interacts with multiple pancreatic digestive enzymes in vivo (identified by MS after acid quenching and thiol alkylation to stabilize transient disulfide-linked complexes). PDIp prevents aggregation of proelastase in cultured cells when co-expressed, and enhances secretion of properly folded proelastase that can be activated by trypsin, establishing digestive enzymes as physiological substrates.\",\n      \"method\": \"Acid quenching/thiol alkylation to trap complexes, MS identification of endogenous substrates from mouse pancreas, co-expression experiments in cultured cells\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vivo substrate trapping with MS plus cell-based reconstitution with functional readout, multiple orthogonal methods\",\n      \"pmids\": [\"30315102\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"PDIA2 translocates from the ER to mitochondria under AOM/DSS-induced ER stress conditions in colon cancer, where it interacts with components of mitochondrial complexes I and II to inhibit oxidative phosphorylation and increase glycolysis. Knockdown of PDIA2 in colon cancer cells restores the metabolic balance and suppresses xenograft tumor growth.\",\n      \"method\": \"Co-immunoprecipitation (PDIA2 with complex I/II components), subcellular fractionation/localization, metabolic assays (oxygen flux, extracellular acidification, targeted metabolomics), xenograft model with PDIA2 knockdown\",\n      \"journal\": \"Frontiers in oncology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP plus metabolic assays plus in vivo knockdown, single lab\",\n      \"pmids\": [\"35860571\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"PDIA2 activates tissue factor (TF) on tumor-derived extracellular vesicles (EVs) through its isomerase activity, triggering a pro-thrombotic cascade. TF-containing EVs also activate Src kinase inside PCa cells to enhance androgen receptor (AR) signaling ligand-independently. Androgen deprivation suppresses clathrin-dependent endocytosis, enhancing PDIA2 translocation to the cell membrane and EVs. Co-recruitment of AR and FOXA1 to the PDIA2 promoter is required for PDIA2 transcription under androgen-deprived conditions. Blocking PDIA2 isomerase activity suppresses pro-coagulation activity and castrate-resistant tumor growth.\",\n      \"method\": \"In vitro and in vivo models, EV isolation and characterization, TF activity assay, isomerase inhibition experiments, Src kinase activation assay, chromatin immunoprecipitation (AR/FOXA1 at PDIA2 promoter), xenograft models\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple in vitro and in vivo methods, single lab, mechanistic pathway established\",\n      \"pmids\": [\"38589675\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"PDIA2 (PDIp) is a pancreas-enriched ER-resident protein disulfide isomerase that catalyzes thiol-disulfide exchange reactions to assist folding of secretory proteins (especially pancreatic digestive enzymes), acts as a molecular chaperone independently of its enzymatic activity by forming stable complexes with denatured substrates, binds and sequesters estradiol in pancreatic tissue, is regulated by redox-dependent inter-subunit disulfide bond formation (via Cys-4), and under stress conditions can translocate to mitochondria or the cell surface/EVs where its isomerase activity activates tissue factor to promote pro-thrombotic and pro-tumorigenic signaling.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"PDIA2 (PDIp) is a pancreas-enriched, ER-resident protein disulfide isomerase that catalyzes thiol-disulfide exchange to assist folding of secretory proteins, particularly pancreatic digestive enzymes [#0, #12]. It carries two thioredoxin-like active sites and an ER retention signal, and reconstituted recombinant protein catalyzes reductive cleavage of insulin and renaturation of reduced RNaseA [#0]. Beyond its catalytic role, PDIA2 acts as a molecular chaperone independently of its isomerase activity: alkylation or mutation of active-site cysteines abolishes enzymatic function while preserving the ability to form stable, stoichiometric complexes with denatured substrates and to prevent aggregation, an activity retained by the active-site-free b-b' fragment [#7]. It recognizes substrates through exposed aromatic (tyrosine/tryptophan) and hydroxyaryl motifs [#3, #4], and in vivo it physically engages multiple pancreatic digestive enzymes, preventing proelastase aggregation and enhancing secretion of activatable, properly folded enzyme [#12]. PDIA2 is a glycoprotein whose N-glycosylation (notably at N284) modulates inter-subunit disulfide-bonded dimer formation, and a non-active-site Cys-4 mediates redox-dependent dimerization that exposes hydrophobic patches and enhances chaperone activity under oxidizing conditions [#6, #9]. The hydroxyaryl-binding b-b' domain also binds 17\\u03b2-estradiol via His278, allowing PDIp to act as a high-capacity intracellular estradiol reservoir in pancreatic tissue that protects bound E2 from metabolic disposition [#5, #10, #11]. Under stress, PDIA2 acquires non-canonical localizations and functions: it translocates from the ER to mitochondria in colon cancer to interact with complex I/II components, inhibiting oxidative phosphorylation and promoting glycolysis and tumor growth [#13], and it is exported to the cell surface and extracellular vesicles where its isomerase activity activates tissue factor to drive pro-thrombotic signaling and ligand-independent androgen receptor activation via Src in prostate cancer [#14].\",\n  \"teleology\": [\n    {\n      \"year\": 1996,\n      \"claim\": \"Established that PDIA2 is a bona fide protein disulfide isomerase, defining its core catalytic identity through its two thioredoxin-like active sites and demonstrated thiol-disulfide exchange activity.\",\n      \"evidence\": \"Recombinant protein expression with in vitro insulin reductive cleavage and RNaseA renaturation assays\",\n      \"pmids\": [\"8561901\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not identify physiological substrates\", \"Tissue-specific expression context not yet defined\"]\n    },\n    {\n      \"year\": 1997,\n      \"claim\": \"Located PDIA2 expression to pancreatic acinar cells as a glycoprotein and showed conservation across species, establishing it as a tissue-restricted secretory-pathway PDI.\",\n      \"evidence\": \"Western blot with PNGase F deglycosylation, immunohistochemistry, and cross-species detection; cross-linking in dog pancreas microsomes during translocation\",\n      \"pmids\": [\"9115635\", \"9136904\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional role of glycosylation unresolved\", \"Specific secretory substrates not identified\"]\n    },\n    {\n      \"year\": 2001,\n      \"claim\": \"Defined the molecular recognition code for PDIA2 substrate binding, showing that aromatic and hydroxyaryl groups serve as docking motifs and rationalizing later ligand-binding behavior.\",\n      \"evidence\": \"Cross-linking with radiolabeled peptide variants and competition with non-peptide hydroxyaryl ligands in pancreas microsome extracts\",\n      \"pmids\": [\"10794419\", \"11237859\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Did not establish which native proteins these motifs map to\", \"Binding-site residues not yet mapped\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Separated PDIA2's chaperone function from its enzymatic activity, demonstrating that aggregation prevention and stress protection persist when active-site cysteines are abolished.\",\n      \"evidence\": \"Iodoacetamide alkylation, active-site mutagenesis, b-b' fragment expression, in vitro aggregation assays, and E. coli stress-protection assay\",\n      \"pmids\": [\"20423326\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"In-cell relevance of enzyme-independent chaperoning not directly tested\", \"Substrate spectrum for chaperone mode undefined\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Showed that redox state and N-glycosylation regulate PDIA2 quaternary structure, linking Cys-4 dimerization and N284 glycosylation to modulation of chaperone activity and protein interactions.\",\n      \"evidence\": \"Redox-dependent dimerization, protease sensitivity and chaperone assays with cysteine mutagenesis; site-directed glycosylation mutants with localization and MHC class I pulldown\",\n      \"pmids\": [\"19150607\", \"23167757\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Physiological trigger for dimerization in pancreas not defined\", \"Functional significance of MHC class I interaction not pursued\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Characterized PDIA2 as a high-capacity intracellular estradiol-binding protein, identifying His278 in the b-b' domain as the binding determinant and establishing a reservoir role in pancreatic tissue.\",\n      \"evidence\": \"Radioligand E2 binding assays, endogenous protein purification, in vivo ovariectomized rat model, and homology modeling with binding-site mutagenesis\",\n      \"pmids\": [\"19429457\", \"22747530\", \"23931275\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Physiological consequence of pancreatic E2 sequestration on signaling not fully resolved\", \"Single-lab assays\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Identified pancreatic digestive enzymes as physiological PDIA2 substrates in vivo, confirming its predicted role in folding and secretion of secretory cargo.\",\n      \"evidence\": \"Acid-quench/thiol-alkylation substrate trapping with MS from mouse pancreas plus co-expression rescue of proelastase folding and secretion\",\n      \"pmids\": [\"30315102\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Full substrate repertoire not exhaustively defined\", \"In vivo loss-of-function consequences in pancreas not assessed\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Revealed non-ER, disease-associated functions of PDIA2, where stress-induced relocalization to mitochondria or to extracellular vesicles reprograms metabolism and activates tissue factor / AR signaling to drive tumor progression.\",\n      \"evidence\": \"Co-IP with mitochondrial complex I/II, metabolic and xenograft assays in colon cancer; EV isolation, TF activity and isomerase inhibition, Src activation, and AR/FOXA1 ChIP at the PDIA2 promoter in prostate cancer\",\n      \"pmids\": [\"35860571\", \"38589675\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of ER-to-mitochondria translocation not defined\", \"Single-lab reports for each non-canonical function\", \"Direct structural confirmation of TF activation by PDIA2 isomerase lacking\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How PDIA2 is trafficked out of the ER to mitochondria, plasma membrane, and EVs under stress, and whether its pancreatic folding role and its tumor-associated moonlighting functions are mechanistically connected, remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structure of full-length PDIA2 or its substrate complexes\", \"Trafficking determinants for non-ER localization unknown\", \"Loss-of-function pancreatic phenotype uncharacterized\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016853\", \"supporting_discovery_ids\": [0, 8, 14]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [0, 12]},\n      {\"term_id\": \"GO:0044183\", \"supporting_discovery_ids\": [7, 12]},\n      {\"term_id\": \"GO:0140313\", \"supporting_discovery_ids\": [5, 10]},\n      {\"term_id\": \"GO:0008289\", \"supporting_discovery_ids\": [5, 10, 11]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005783\", \"supporting_discovery_ids\": [0, 2, 9]},\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [13]},\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [14]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-392499\", \"supporting_discovery_ids\": [0, 7, 12]},\n      {\"term_id\": \"R-HSA-1643685\", \"supporting_discovery_ids\": [13, 14]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"TF\", \"AR\", \"FOXA1\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}