{"gene":"PSMB7","run_date":"2026-06-10T06:43:36","timeline":{"discoveries":[{"year":2013,"finding":"Knockdown of PSMB7 in neonatal cardiomyocytes via siRNA specifically decreased peptidyl-glutamyl peptide-hydrolyzing (caspase-like) proteasome activity without affecting chymotrypsin-like or trypsin-like activities, indicating that PSMB7 contributes selectively to this catalytic activity of the 20S proteasome.","method":"siRNA knockdown + proteasome activity assays (chymotrypsin-like, trypsin-like, peptidyl-glutamyl peptide-hydrolyzing) in isolated neonatal cardiomyocytes","journal":"Pathobiology : journal of immunopathology, molecular and cellular biology","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — clean siRNA knockdown with specific enzymatic activity readout in a defined cell type, single lab, single study","pmids":["23969338"],"is_preprint":false},{"year":2013,"finding":"PSMB7 knockdown in cardiomyocytes induced ER stress, as evidenced by increased mRNA expression of DDIT3/CHOP and HSPA5/GRP78, and triggered autophagy marked by increased LC3-positive vacuoles and monodansylcadaverine (MDC)-labeled autophagic vacuoles; the effect was exacerbated after anoxia-reoxygenation.","method":"siRNA knockdown + single-cell RT-qPCR for ER stress markers (DDIT3/CHOP, HSPA5/GRP78) + immunohistochemistry for LC3 + MDC staining for autophagic vacuoles in neonatal cardiomyocytes","journal":"Pathobiology : journal of immunopathology, molecular and cellular biology","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — multiple orthogonal readouts (molecular markers + morphological) in a single lab study linking PSMB7 loss to ER stress and autophagy induction","pmids":["23969338"],"is_preprint":false}],"current_model":"PSMB7 (proteasome subunit beta-7) contributes specifically to the peptidyl-glutamyl peptide-hydrolyzing (caspase-like) catalytic activity of the 20S proteasome; its loss in cardiomyocytes triggers ER stress (upregulation of CHOP and GRP78) and autophagy induction (LC3-positive vacuole accumulation), suggesting that PSMB7-dependent proteasomal activity suppresses autophagic and ER stress responses under basal and ischemic conditions."},"narrative":{"mechanistic_narrative":"PSMB7 (proteasome subunit beta-7) contributes selectively to the peptidyl-glutamyl peptide-hydrolyzing (caspase-like) catalytic activity of the 20S proteasome, as its knockdown in cardiomyocytes specifically reduces this activity without affecting chymotrypsin-like or trypsin-like activities [PMID:23969338]. Loss of PSMB7-dependent proteasomal activity induces ER stress, marked by upregulation of DDIT3/CHOP and HSPA5/GRP78, and triggers autophagy, evidenced by accumulation of LC3-positive and MDC-labeled autophagic vacuoles, with these responses exacerbated by anoxia-reoxygenation [PMID:23969338]. Beyond these cardiomyocyte loss-of-function findings, no further mechanistic detail on PSMB7 has been characterized in the available corpus.","teleology":[{"year":2013,"claim":"It was unknown which catalytic activity of the 20S proteasome PSMB7 supports; selective depletion established that PSMB7 contributes specifically to the caspase-like (peptidyl-glutamyl peptide-hydrolyzing) activity.","evidence":"siRNA knockdown with three proteasome activity assays in isolated neonatal cardiomyocytes","pmids":["23969338"],"confidence":"Medium","gaps":["Single lab, single study without structural confirmation of the active site contribution","No reconstitution demonstrating direct catalytic role","Restricted to one cell type (cardiomyocytes)"]},{"year":2013,"claim":"The cellular consequence of losing PSMB7 activity was undefined; knockdown showed that reduced caspase-like proteasome activity drives ER stress and autophagy, linking PSMB7 to proteostatic stress responses under ischemic conditions.","evidence":"siRNA knockdown with RT-qPCR for ER stress markers, LC3 immunohistochemistry, and MDC staining, with anoxia-reoxygenation in neonatal cardiomyocytes","pmids":["23969338"],"confidence":"Medium","gaps":["Causal mechanism linking caspase-like activity loss to CHOP/GRP78 induction not defined","Whether autophagy induction is protective or detrimental not resolved","No in vivo validation beyond isolated cardiomyocytes"]},{"year":null,"claim":"Whether PSMB7's role extends beyond cardiomyocyte proteostasis and how it integrates into broader proteasome assembly and substrate selection remains unestablished in the available corpus.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural or assembly-context data for PSMB7 in the timeline","No identified physical partners or substrates","No tissue-context beyond cardiomyocytes"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[0]},{"term_id":"GO:0016787","term_label":"hydrolase activity","supporting_discovery_ids":[0]}],"localization":[],"pathway":[{"term_id":"R-HSA-392499","term_label":"Metabolism of proteins","supporting_discovery_ids":[0]}],"complexes":["20S proteasome"],"partners":[],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q99436","full_name":"Proteasome subunit beta type-7","aliases":["Macropain chain Z","Multicatalytic endopeptidase complex chain Z","Proteasome subunit Z","Proteasome subunit beta-2","beta-2"],"length_aa":277,"mass_kda":30.0,"function":"Component of the 20S core proteasome complex involved in the proteolytic degradation of most intracellular proteins. This complex plays numerous essential roles within the cell by associating with different regulatory particles. Associated with two 19S regulatory particles, forms the 26S proteasome and thus participates in the ATP-dependent degradation of ubiquitinated proteins. The 26S proteasome plays a key role in the maintenance of protein homeostasis by removing misfolded or damaged proteins that could impair cellular functions, and by removing proteins whose functions are no longer required. Associated with the PA200 or PA28, the 20S proteasome mediates ubiquitin-independent protein degradation. This type of proteolysis is required in several pathways including spermatogenesis (20S-PA200 complex) or generation of a subset of MHC class I-presented antigenic peptides (20S-PA28 complex). Within the 20S core complex, PSMB7 displays a trypsin-like activity","subcellular_location":"Cytoplasm; Nucleus","url":"https://www.uniprot.org/uniprotkb/Q99436/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":true,"resolved_as":"","url":"https://depmap.org/portal/gene/PSMB7","classification":"Common 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PSMB11","url":"https://www.omim.org/entry/611137"},{"mim_id":"604030","title":"PROTEASOME SUBUNIT, BETA-TYPE, 7; PSMB7","url":"https://www.omim.org/entry/604030"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoplasm","reliability":"Supported"},{"location":"Nuclear bodies","reliability":"Additional"},{"location":"Primary cilium","reliability":"Additional"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/PSMB7"},"hgnc":{"alias_symbol":["Z"],"prev_symbol":[]},"alphafold":{"accession":"Q99436","domains":[{"cath_id":"3.60.20.10","chopping":"40-232","consensus_level":"medium","plddt":95.3634,"start":40,"end":232}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q99436","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q99436-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q99436-F1-predicted_aligned_error_v6.png","plddt_mean":90.38},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=PSMB7","jax_strain_url":"https://www.jax.org/strain/search?query=PSMB7"},"sequence":{"accession":"Q99436","fasta_url":"https://rest.uniprot.org/uniprotkb/Q99436.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q99436/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q99436"}},"corpus_meta":[{"pmid":"32200799","id":"PMC_32200799","title":"Influenza Virus Z-RNAs Induce 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Cause or effect?","date":"2014","source":"Cancer metastasis reviews","url":"https://pubmed.ncbi.nlm.nih.gov/24398858","citation_count":27,"is_preprint":false},{"pmid":"31015444","id":"PMC_31015444","title":"The H2A.Z histone variant integrates Wnt signaling in intestinal epithelial homeostasis.","date":"2019","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/31015444","citation_count":27,"is_preprint":false},{"pmid":"33217681","id":"PMC_33217681","title":"Variation on a theme: Evolutionary strategies for H2A.Z exchange by SWR1-type remodelers.","date":"2020","source":"Current opinion in cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/33217681","citation_count":27,"is_preprint":false},{"pmid":"25839232","id":"PMC_25839232","title":"Expression of Non-acetylatable H2A.Z in Myoblast Cells Blocks Myoblast Differentiation through Disruption of MyoD Expression.","date":"2015","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/25839232","citation_count":26,"is_preprint":false},{"pmid":"31544922","id":"PMC_31544922","title":"Interbase FRET in RNA: from A to Z.","date":"2019","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/31544922","citation_count":25,"is_preprint":false},{"pmid":"31527837","id":"PMC_31527837","title":"DNA repair complex licenses acetylation of H2A.Z.1 by KAT2A during transcription.","date":"2019","source":"Nature chemical biology","url":"https://pubmed.ncbi.nlm.nih.gov/31527837","citation_count":25,"is_preprint":false},{"pmid":"34139016","id":"PMC_34139016","title":"INO80 promotes H2A.Z occupancy to regulate cell fate transition in pluripotent stem cells.","date":"2021","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/34139016","citation_count":25,"is_preprint":false},{"pmid":"22535494","id":"PMC_22535494","title":"Retrogenes moved out of the z chromosome in the silkworm.","date":"2012","source":"Journal of molecular evolution","url":"https://pubmed.ncbi.nlm.nih.gov/22535494","citation_count":25,"is_preprint":false},{"pmid":"29532867","id":"PMC_29532867","title":"H2A.Z regulates tumorigenesis, metastasis and sensitivity to cisplatin in intrahepatic cholangiocarcinoma.","date":"2018","source":"International journal of oncology","url":"https://pubmed.ncbi.nlm.nih.gov/29532867","citation_count":25,"is_preprint":false},{"pmid":"35606214","id":"PMC_35606214","title":"H2A.Z's 'social' network: functional partners of an enigmatic histone variant.","date":"2022","source":"Trends in biochemical sciences","url":"https://pubmed.ncbi.nlm.nih.gov/35606214","citation_count":24,"is_preprint":false},{"pmid":"35054954","id":"PMC_35054954","title":"Searching for New Z-DNA/Z-RNA Binding Proteins Based on Structural Similarity to Experimentally Validated Zα Domain.","date":"2022","source":"International journal of molecular sciences","url":"https://pubmed.ncbi.nlm.nih.gov/35054954","citation_count":24,"is_preprint":false},{"pmid":"17305600","id":"PMC_17305600","title":"tRNase Z.","date":"2007","source":"Protein and peptide letters","url":"https://pubmed.ncbi.nlm.nih.gov/17305600","citation_count":23,"is_preprint":false},{"pmid":"33744929","id":"PMC_33744929","title":"Sequence-dependent cost for Z-form shapes the torsion-driven B-Z transition via close interplay of Z-DNA and DNA bubble.","date":"2021","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/33744929","citation_count":22,"is_preprint":false},{"pmid":"30355979","id":"PMC_30355979","title":"Thermodynamic Model for B-Z Transition of DNA Induced by Z-DNA Binding Proteins.","date":"2018","source":"Molecules (Basel, Switzerland)","url":"https://pubmed.ncbi.nlm.nih.gov/30355979","citation_count":21,"is_preprint":false},{"pmid":"39092141","id":"PMC_39092141","title":"The ancient Z-DNA and Z-RNA specific Zα fold has evolved modern roles in immunity and transcription through the natural selection of flipons.","date":"2024","source":"Royal Society open science","url":"https://pubmed.ncbi.nlm.nih.gov/39092141","citation_count":21,"is_preprint":false},{"pmid":"32708675","id":"PMC_32708675","title":"VPS72/YL1-Mediated H2A.Z Deposition Is Required for Nuclear Reassembly after Mitosis.","date":"2020","source":"Cells","url":"https://pubmed.ncbi.nlm.nih.gov/32708675","citation_count":21,"is_preprint":false},{"pmid":"36888706","id":"PMC_36888706","title":"The TORC1 activates Rpd3L complex to deacetylate Ino80 and H2A.Z and repress autophagy.","date":"2023","source":"Science advances","url":"https://pubmed.ncbi.nlm.nih.gov/36888706","citation_count":20,"is_preprint":false},{"pmid":"33438773","id":"PMC_33438773","title":"ZSP-1 is a Z granule surface protein required for Z granule fluidity and germline immortality in Caenorhabditis elegans.","date":"2021","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/33438773","citation_count":20,"is_preprint":false},{"pmid":"19181098","id":"PMC_19181098","title":"The Z-disk diseases.","date":"2008","source":"Advances in experimental medicine and biology","url":"https://pubmed.ncbi.nlm.nih.gov/19181098","citation_count":19,"is_preprint":false},{"pmid":"37164635","id":"PMC_37164635","title":"Z-flipon variants reveal the many roles of Z-DNA and Z-RNA in health and disease.","date":"2023","source":"Life science alliance","url":"https://pubmed.ncbi.nlm.nih.gov/37164635","citation_count":19,"is_preprint":false},{"pmid":"35074916","id":"PMC_35074916","title":"Sex-specific splicing of Z- and W-borne nr5a1 alleles suggests sex determination is controlled by chromosome conformation.","date":"2022","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/35074916","citation_count":19,"is_preprint":false},{"pmid":"33245772","id":"PMC_33245772","title":"Dual conformational recognition by Z-DNA binding protein is important for the B-Z transition process.","date":"2020","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/33245772","citation_count":18,"is_preprint":false},{"pmid":"32547065","id":"PMC_32547065","title":"Vital and Distinct Roles of H2A.Z Isoforms in Hepatocellular Carcinoma.","date":"2020","source":"OncoTargets and therapy","url":"https://pubmed.ncbi.nlm.nih.gov/32547065","citation_count":18,"is_preprint":false},{"pmid":"39374087","id":"PMC_39374087","title":"Role of Z-DNA Binding Protein 1 Sensing Mitochondrial Z-DNA and Triggering Necroptosis in Oxalate-Induced Acute Kidney Injury.","date":"2024","source":"Journal of the American Society of Nephrology : JASN","url":"https://pubmed.ncbi.nlm.nih.gov/39374087","citation_count":17,"is_preprint":false},{"pmid":"23969338","id":"PMC_23969338","title":"Knockdown of PSMB7 induces autophagy in cardiomyocyte cultures: possible role in endoplasmic reticulum stress.","date":"2013","source":"Pathobiology : journal of immunopathology, molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/23969338","citation_count":17,"is_preprint":false},{"pmid":"37536340","id":"PMC_37536340","title":"Structural insight into H4K20 methylation on H2A.Z-nucleosome by SUV420H1.","date":"2023","source":"Molecular cell","url":"https://pubmed.ncbi.nlm.nih.gov/37536340","citation_count":17,"is_preprint":false},{"pmid":"35503594","id":"PMC_35503594","title":"GAS41 mediates proliferation and GEM chemoresistance via H2A.Z.2 and Notch1 in pancreatic cancer.","date":"2022","source":"Cellular oncology (Dordrecht, Netherlands)","url":"https://pubmed.ncbi.nlm.nih.gov/35503594","citation_count":17,"is_preprint":false},{"pmid":"32900832","id":"PMC_32900832","title":"ylm Has More than a (Z Anchor) Ring to It!","date":"2021","source":"Journal of bacteriology","url":"https://pubmed.ncbi.nlm.nih.gov/32900832","citation_count":16,"is_preprint":false},{"pmid":"36709316","id":"PMC_36709316","title":"The H2A.Z and NuRD associated protein HMG20A controls early head and heart developmental transcription programs.","date":"2023","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/36709316","citation_count":16,"is_preprint":false},{"pmid":"36396651","id":"PMC_36396651","title":"H2A.Z deposition by SWR1C involves multiple ATP-dependent steps.","date":"2022","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/36396651","citation_count":16,"is_preprint":false},{"pmid":"28883625","id":"PMC_28883625","title":"Redundant Functions for Nap1 and Chz1 in H2A.Z Deposition.","date":"2017","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/28883625","citation_count":16,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":39237,"output_tokens":1046,"usd":0.0667,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":7099,"output_tokens":1274,"usd":0.033673,"stage2_stop_reason":"end_turn"},"total_usd":0.100373,"stage1_batch_id":"msgbatch_01CNoDbkChHEkgrJnL7BwtGJ","stage2_batch_id":"msgbatch_016Y4x9E9Wg5VQDANj9quSQD","note":"batch pricing = 50% of standard"},"stage1_raw":"Looking at the corpus, I need to identify papers about PSMB7. The gene symbol is PSMB7 (also known as \"Z\" per the HGNC aliases). However, reviewing the aliases carefully: \"Z\" is listed as an alias for PSMB7. But looking at all 100 papers, they overwhelmingly discuss H2A.Z (a histone variant), Z-DNA/Z-RNA biology, Protein Z (coagulation factor), bacterial FtsZ, and other \"Z\"-named entities — none of which are PSMB7 (Proteasome Subunit Beta 7).\n\nOnly paper [94] is actually about PSMB7: \"Knockdown of PSMB7 induces autophagy in cardiomyocyte cultures: possible role in endoplasmic reticulum stress\" (PMID: 23969338). This paper directly names PSMB7 and studies its function.\n\nAll other papers describe H2A.Z (histone variant), Z-DNA, Protein Z (coagulation), FtsZ (bacterial tubulin homolog), tRNase Z, ZBP1, etc. — none of these are PSMB7 (proteasome beta-7 subunit). The \"Z\" alias for PSMB7 appears to have caused retrieval of many unrelated papers.\n\n```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2013,\n      \"finding\": \"Knockdown of PSMB7 in neonatal cardiomyocytes via siRNA specifically decreased peptidyl-glutamyl peptide-hydrolyzing (caspase-like) proteasome activity without affecting chymotrypsin-like or trypsin-like activities, indicating that PSMB7 contributes selectively to this catalytic activity of the 20S proteasome.\",\n      \"method\": \"siRNA knockdown + proteasome activity assays (chymotrypsin-like, trypsin-like, peptidyl-glutamyl peptide-hydrolyzing) in isolated neonatal cardiomyocytes\",\n      \"journal\": \"Pathobiology : journal of immunopathology, molecular and cellular biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — clean siRNA knockdown with specific enzymatic activity readout in a defined cell type, single lab, single study\",\n      \"pmids\": [\"23969338\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"PSMB7 knockdown in cardiomyocytes induced ER stress, as evidenced by increased mRNA expression of DDIT3/CHOP and HSPA5/GRP78, and triggered autophagy marked by increased LC3-positive vacuoles and monodansylcadaverine (MDC)-labeled autophagic vacuoles; the effect was exacerbated after anoxia-reoxygenation.\",\n      \"method\": \"siRNA knockdown + single-cell RT-qPCR for ER stress markers (DDIT3/CHOP, HSPA5/GRP78) + immunohistochemistry for LC3 + MDC staining for autophagic vacuoles in neonatal cardiomyocytes\",\n      \"journal\": \"Pathobiology : journal of immunopathology, molecular and cellular biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — multiple orthogonal readouts (molecular markers + morphological) in a single lab study linking PSMB7 loss to ER stress and autophagy induction\",\n      \"pmids\": [\"23969338\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"PSMB7 (proteasome subunit beta-7) contributes specifically to the peptidyl-glutamyl peptide-hydrolyzing (caspase-like) catalytic activity of the 20S proteasome; its loss in cardiomyocytes triggers ER stress (upregulation of CHOP and GRP78) and autophagy induction (LC3-positive vacuole accumulation), suggesting that PSMB7-dependent proteasomal activity suppresses autophagic and ER stress responses under basal and ischemic conditions.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"PSMB7 (proteasome subunit beta-7) contributes selectively to the peptidyl-glutamyl peptide-hydrolyzing (caspase-like) catalytic activity of the 20S proteasome, as its knockdown in cardiomyocytes specifically reduces this activity without affecting chymotrypsin-like or trypsin-like activities [#0]. Loss of PSMB7-dependent proteasomal activity induces ER stress, marked by upregulation of DDIT3/CHOP and HSPA5/GRP78, and triggers autophagy, evidenced by accumulation of LC3-positive and MDC-labeled autophagic vacuoles, with these responses exacerbated by anoxia-reoxygenation [#1]. Beyond these cardiomyocyte loss-of-function findings, no further mechanistic detail on PSMB7 has been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 2013,\n      \"claim\": \"It was unknown which catalytic activity of the 20S proteasome PSMB7 supports; selective depletion established that PSMB7 contributes specifically to the caspase-like (peptidyl-glutamyl peptide-hydrolyzing) activity.\",\n      \"evidence\": \"siRNA knockdown with three proteasome activity assays in isolated neonatal cardiomyocytes\",\n      \"pmids\": [\"23969338\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Single lab, single study without structural confirmation of the active site contribution\",\n        \"No reconstitution demonstrating direct catalytic role\",\n        \"Restricted to one cell type (cardiomyocytes)\"\n      ]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"The cellular consequence of losing PSMB7 activity was undefined; knockdown showed that reduced caspase-like proteasome activity drives ER stress and autophagy, linking PSMB7 to proteostatic stress responses under ischemic conditions.\",\n      \"evidence\": \"siRNA knockdown with RT-qPCR for ER stress markers, LC3 immunohistochemistry, and MDC staining, with anoxia-reoxygenation in neonatal cardiomyocytes\",\n      \"pmids\": [\"23969338\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Causal mechanism linking caspase-like activity loss to CHOP/GRP78 induction not defined\",\n        \"Whether autophagy induction is protective or detrimental not resolved\",\n        \"No in vivo validation beyond isolated cardiomyocytes\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"Whether PSMB7's role extends beyond cardiomyocyte proteostasis and how it integrates into broader proteasome assembly and substrate selection remains unestablished in the available corpus.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No structural or assembly-context data for PSMB7 in the timeline\",\n        \"No identified physical partners or substrates\",\n        \"No tissue-context beyond cardiomyocytes\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0016787\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"localization\": [],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-392499\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"complexes\": [\"20S proteasome\"],\n    \"partners\": [],\n    \"other_free_text\": []\n  }\n}\n```","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":2,"faith_total":2,"faith_pct":100.0}}