{"gene":"ICA1","run_date":"2026-06-10T01:55:22","timeline":{"discoveries":[{"year":1993,"finding":"ICA69 (product of ICA1) is a novel 483-amino acid protein expressed in pancreatic beta cells, brain, heart, thyroid, and kidney, with the native molecule migrating at 69 kDa in SDS-PAGE; its mRNA was detected in beta cell lines and islet-cell tumoral tissue, establishing tissue distribution by direct molecular cloning and expression analysis.","method":"Lambda gt11 cDNA library screening, Western blotting with specific antibodies, Northern blotting, SDS-PAGE","journal":"The Journal of clinical investigation","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — molecular cloning with protein characterization, single lab, multiple orthogonal methods (Northern blot, Western blot, SDS-PAGE)","pmids":["8326004"],"is_preprint":false},{"year":2000,"finding":"ICA69 and its C. elegans homologue RIC-19 are conserved regulators of neuroendocrine secretion: a subpopulation of ICA69 is membrane-bound and co-enriched with synaptic vesicles in mouse brain; in beta cells it localizes to synaptic-like microvesicles. Deletion of ric-19 in C. elegans causes aldicarb resistance (defective neurotransmitter secretion), rescued by ric-19 transgene.","method":"Subcellular fractionation, immunostaining, C. elegans deletion mutant with aldicarb resistance assay, transgenic rescue","journal":"Molecular biology of the cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (fractionation, localization, genetic loss-of-function, transgenic rescue) across two organisms, replicated concept","pmids":["11029035"],"is_preprint":false},{"year":2007,"finding":"ICA69 is the major binding partner of PICK1 in the brain (>75% of each protein associates with the other); the BAR domain of ICA69 forms heteromeric BAR domain complexes with PICK1 and binds liposomes. ICA69 overexpression redistributes PICK1 from synapses to dendrites, disrupts PICK1-induced AMPA receptor clustering, and reduces synaptic targeting and surface expression of AMPA receptors, indicating that the switch between ICA69-PICK1 heteromers and PICK1 homomers regulates AMPAR trafficking.","method":"Co-immunoprecipitation, liposome-binding assay, overexpression in neurons, immunofluorescence colocalization, surface AMPAR quantification","journal":"The Journal of neuroscience","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP from brain, liposome binding, functional overexpression with defined AMPAR phenotype, multiple orthogonal methods in one study","pmids":["18032668"],"is_preprint":false},{"year":2008,"finding":"ICA69 is a novel Rab2 effector: it binds to Rab2 in a GTP-dependent manner, and Rab2 recruits ICA69 to membranes. Over-expression of either Rab2 or ICA69 in insulinoma INS-1 cells impairs anterograde transport of secretory granule protein precursors (pro-ICA512, chromogranin A) and reduces stimulated insulin secretion, placing ICA69 in ER-Golgi COPI vesicle transport.","method":"Co-immunoprecipitation (GTP-dependent), membrane recruitment assay, overexpression in INS-1 cells, pulse-chase secretory granule trafficking assay, insulin secretion assay","journal":"European journal of cell biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — GTP-dependent binding with Co-IP, functional trafficking and secretion assays with multiple readouts, single lab but multiple orthogonal methods","pmids":["18187231"],"is_preprint":false},{"year":2002,"finding":"Genetic disruption of the ICA69 locus in NOD mice prevents lacrimal gland autoimmune disease and greatly reduces salivary gland disease; ICA69-specific T cells accumulate in lymph nodes draining salivary tissue in healthy NOD mice, establishing ICA69 as a functionally required autoantigen in Sjögren's syndrome progression.","method":"Genomic knockout (ICA69-null NOD congenic mice), histopathological assessment, T-cell immunophenotyping, peptide immunotherapy","journal":"Lancet","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean genetic knockout with defined organ-specific disease phenotype, multiple immunological readouts, replicated in multiple NOD cohorts","pmids":["12383988"],"is_preprint":false},{"year":2002,"finding":"ICA69-null NOD mice develop spontaneous diabetes and insulitis normally but are resistant to cyclophosphamide-accelerated diabetes; transplantation experiments linked this resistance to ICA69 deficiency specifically in islets (not in the hematopoietic compartment), indicating ICA69-dependent beta-cell drug toxicity contributes to CY-accelerated autoimmunity.","method":"ICA69 knockout mice, cyclophosphamide treatment, islet and hematopoietic tissue transplantation, diabetes incidence assay","journal":"Journal of immunology","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic knockout with tissue-specific transplantation epistasis experiments defining islet-autonomous function","pmids":["11751995"],"is_preprint":false},{"year":2013,"finding":"The C-terminal domain of ICA69 (ICAC) interacts with PICK1 and inhibits PKCα-mediated trafficking of the PICK1-PKCα complex to the plasma membrane; overexpression of ICAC (but not the BAR domain alone) blocks this trafficking. Infusion of MBP-ICA69 or MBP-ICAC into cerebellar Purkinje cells inhibits induction of long-term depression at parallel fiber and climbing fiber synapses.","method":"Co-immunoprecipitation, overexpression of domain deletion constructs, fluorescence imaging of PICK1-PKCα trafficking, intracellular protein infusion with electrophysiological LTD recording","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — domain mapping with Co-IP and trafficking assay, functional LTD recording, single lab","pmids":["24358315"],"is_preprint":false},{"year":2014,"finding":"Thymic-specific deletion of ICA69 (Aire-ΔICA69 mice) causes suboptimal central negative selection of ICA69-reactive T cells and spontaneous multi-organ autoimmunity (pancreas, salivary glands, thyroid, stomach), establishing a direct causal link between thymic ICA69 expression and maintenance of peripheral self-tolerance.","method":"Tissue-specific conditional knockout (Aire-Cre driven), histological analysis of organ inflammation, T-cell tolerance assays","journal":"Journal of autoimmunity","confidence":"High","confidence_rationale":"Tier 2 / Strong — conditional genetic knockout with defined multi-organ phenotype and mechanistic link to central tolerance, multiple orthogonal readouts","pmids":["25088457"],"is_preprint":false},{"year":2014,"finding":"Loss of ICA69 in mice reduces PICK1 protein levels in spinal cord, increases Ser880 phosphorylation of GluA2 and decreases surface GluA2 expression, leading to enhanced inflammatory pain hypersensitivity after formalin injection; microglial activation in the spinal dorsal horn was also increased.","method":"ICA69 knockout mice, formalin pain assay, Western blotting for GluA2 phosphorylation and surface expression, immunohistochemistry for microglial activation","journal":"Neurochemical research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic KO with defined pain phenotype and biochemical AMPAR readouts, single lab, multiple methods","pmids":["25547463"],"is_preprint":false},{"year":2017,"finding":"In Drosophila, ICA69 colocalizes with α-Spectrin at the neuromuscular junction (NMJ); the N-BAR domain deforms liposomes in vitro; full-length ICA69 and ICAC (but not N-BAR alone) induce filopodia in cultured cells. ICA69 mutants show reduced α-Spectrin at the NMJ and altered synaptic glutamate receptor levels. Reducing PICK1 or Rab2 phenocopies ICA69 mutation, and Rab2 functions genetically upstream of ICA69 regulating ICA69 levels and NMJ organization.","method":"RNAi screen, genetic loss-of-function, liposome deformation assay, immunofluorescence colocalization, filopodia induction assay, epistasis analysis","journal":"Development","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — in vitro BAR domain membrane-deformation assay plus genetic epistasis defining pathway order (Rab2→ICA69→PICK1) plus multiple cellular phenotype readouts","pmids":["28455372"],"is_preprint":false},{"year":2012,"finding":"A single nucleotide polymorphism in the NOD mouse Ica1 promoter increases binding affinity for the transcription factor AIRE, which down-regulates ICA69 expression in medullary thymic epithelial cells; luciferase reporter assays showed NOD Ica1 promoter drives markedly reduced expression compared to C57BL/6 in mTEC and B-cell lines.","method":"Luciferase reporter assays, AIRE binding affinity assay, SNP identification, transfection in mTEC and B-cell lines","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reporter assays and direct TF binding measurement, single lab, mechanistically links promoter SNP to AIRE-mediated transcriptional regulation","pmids":["22447927"],"is_preprint":false},{"year":2002,"finding":"The ICA1 gene uses alternative core promoters in a tissue-specific manner: the exon A promoter is more active in islet cells and the exon B promoter in neuronal cells; a CREB site within the exon B promoter negatively regulates transcriptional activity in both cell types.","method":"5'-RACE, luciferase reporter constructs, CREB site mutagenesis, transient transfection in islet (RIN) and neuronal (NMB7) cell lines","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reporter assays with site-directed mutagenesis confirming CREB site function, single lab, multiple cell lines","pmids":["12409289"],"is_preprint":false},{"year":2022,"finding":"ICA69 promotes ferroptosis in LPS-treated cardiomyocytes and macrophages by triggering STING production, which drives intracellular lipid peroxidation. ICA69 knockout in LPS-induced mice elevated survival and heart function, reduced ferroptosis markers (PTGS2, MDA, 4HNE, GPX4, SOD, iron, lipid ROS), and reduced inflammatory cytokines, but had no effect on xCT-dependent pathways.","method":"ICA69 knockout mice, LPS-induced septic cardiomyopathy model, ferroptosis marker quantification (ELISA, Western blot), STING expression analysis","journal":"Cell death discovery","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic KO with defined ferroptosis phenotype and mechanistic STING link, single lab, multiple biochemical readouts","pmids":["35397620"],"is_preprint":false},{"year":2023,"finding":"ICA69 regulates PICK1 protein stability and distribution in the hippocampus. Genetic deletion of ICA69 (Ica1 knockout) selectively impairs NMDAR-dependent LTP but not LTD at Schaffer collateral–CA1 synapses without affecting basal AMPAR-mediated currents, dendritic morphology, or PSD AMPAR levels; this correlates with deficits in spatial and associative learning and memory.","method":"Ica1 knockout mice, electrophysiological LTP/LTD recording, PSD biochemical fractionation, Western blotting, behavioral tests (spatial and associative memory)","journal":"Frontiers in molecular neuroscience","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic KO with electrophysiological LTP specificity, biochemical fractionation, and behavioral readouts; multiple orthogonal methods in single study","pmids":["37251649"],"is_preprint":false},{"year":2024,"finding":"ICA1/ICA69 overexpression increases APP, ADAM10, and ADAM17 protein levels and increases PKCα protein levels and phosphorylation, shifting APP processing toward non-amyloidogenic pathways via the PICK1-PKCα signaling axis; transcriptome analysis indicated ICA1 regulates G protein-coupled receptor signaling.","method":"Overexpression in cell lines, Western blotting for APP/ADAM10/ADAM17/PKCα, transcriptome sequencing, half-life and mRNA level analysis","journal":"CNS neuroscience & therapeutics","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, overexpression-based, no rescue or mutagenesis; pathway assignment inferred from transcriptomics and protein levels without direct mechanistic reconstitution","pmids":["38884369"],"is_preprint":false}],"current_model":"ICA69 (encoded by ICA1) is a BAR-domain-containing cytosolic protein that associates with secretory vesicles and the Golgi, acts as a GTP-dependent effector of Rab2 to regulate ER-Golgi trafficking and insulin secretory granule biogenesis, and in neurons forms heteromeric BAR complexes with PICK1 to control AMPA receptor trafficking, synaptic plasticity (selectively required for LTP), and learning and memory; it also modulates ferroptosis via STING in cardiomyocytes, and its expression level in the thymus—regulated by AIRE through promoter polymorphisms—controls central tolerance to prevent multi-organ autoimmunity."},"narrative":{"mechanistic_narrative":"ICA1 encodes ICA69, a conserved BAR-domain cytosolic protein that links membrane deformation to regulated secretion in both neuroendocrine and neuronal cells [PMID:8326004, PMID:11029035]. A subpopulation associates with synaptic vesicles and synaptic-like microvesicles, and its loss in the C. elegans ortholog RIC-19 impairs neurotransmitter secretion [PMID:11029035]. Mechanistically, ICA69 acts as a GTP-dependent effector of Rab2: Rab2 recruits it to membranes and positions it within ER-Golgi COPI vesicle transport, where it is required for anterograde delivery of secretory granule precursors (pro-ICA512, chromogranin A) and stimulated insulin secretion [PMID:18187231]. Its N-BAR domain binds and deforms liposomes and induces filopodia, and genetic epistasis places it in a Rab2→ICA69→PICK1 pathway controlling synaptic architecture [PMID:28455372]. In neurons, ICA69 is the major brain partner of PICK1, forming heteromeric BAR complexes whose balance against PICK1 homomers governs AMPA receptor clustering, surface expression, and trafficking [PMID:18032668]; through this PICK1 axis it stabilizes PICK1 protein and is selectively required for NMDAR-dependent LTP and for spatial and associative memory [PMID:37251649]. Independently, thymic ICA69 expression — set by AIRE acting on the Ica1 promoter — drives central negative selection of ICA69-reactive T cells, and its loss causes spontaneous multi-organ autoimmunity, establishing ICA69 as a tolerance-controlling autoantigen [PMID:25088457, PMID:22447927]. ICA69 also promotes STING-driven ferroptosis in cardiomyocytes during endotoxemia [PMID:35397620].","teleology":[{"year":1993,"claim":"Established that ICA1 encodes a discrete 69 kDa protein (ICA69) and defined its tissue distribution, providing the molecular entity to study in beta cells and brain.","evidence":"cDNA library screening with Northern, Western, and SDS-PAGE characterization","pmids":["8326004"],"confidence":"Medium","gaps":["No function assigned at this stage","Subcellular localization and binding partners unknown"]},{"year":2000,"claim":"Showed ICA69 is a conserved membrane-associated regulator of neuroendocrine secretion, moving it from an antigen to a vesicle-trafficking protein.","evidence":"Subcellular fractionation and immunostaining in mouse, plus C. elegans ric-19 deletion (aldicarb resistance) with transgenic rescue","pmids":["11029035"],"confidence":"High","gaps":["Molecular partners and the membrane-binding mechanism not yet defined","Direct biochemical role in vesicle budding unresolved"]},{"year":2007,"claim":"Identified PICK1 as the dominant brain partner and defined ICA69-PICK1 heteromeric BAR complexes as a switch controlling AMPA receptor trafficking.","evidence":"Reciprocal Co-IP from brain, liposome binding, and neuronal overexpression with surface AMPAR quantification","pmids":["18032668"],"confidence":"High","gaps":["Effect shown by overexpression rather than endogenous loss-of-function","In vivo synaptic consequence not yet tested"]},{"year":2008,"claim":"Defined ICA69 as a GTP-dependent Rab2 effector required for ER-Golgi anterograde transport and insulin secretion, giving its trafficking role a molecular mechanism.","evidence":"GTP-dependent Co-IP, membrane recruitment, and pulse-chase secretory granule trafficking plus insulin secretion assays in INS-1 cells","pmids":["18187231"],"confidence":"High","gaps":["Direct demonstration of BAR-mediated membrane curvature in this pathway not shown","Relationship between Rab2 and PICK1 functions unaddressed here"]},{"year":2017,"claim":"Ordered the pathway genetically (Rab2→ICA69→PICK1) and demonstrated direct N-BAR membrane deformation, unifying the trafficking and synaptic roles.","evidence":"Drosophila RNAi/genetic loss-of-function, liposome deformation, filopodia induction, and epistasis at the NMJ","pmids":["28455372"],"confidence":"High","gaps":["Structural basis of heteromeric BAR assembly not resolved","Conservation of epistasis order in mammals not directly tested"]},{"year":2013,"claim":"Mapped the C-terminal domain as the PICK1-interacting/PKCα-regulating module and linked ICA69 to cerebellar LTD induction.","evidence":"Domain-deletion Co-IP, PICK1-PKCα trafficking imaging, and protein infusion with LTD electrophysiology in Purkinje cells","pmids":["24358315"],"confidence":"Medium","gaps":["Acute infusion/overexpression rather than genetic loss","Endogenous requirement for LTD not established"]},{"year":2023,"claim":"Defined the in vivo synaptic function: ICA69 stabilizes PICK1 and is selectively required for NMDAR-dependent LTP and for learning and memory.","evidence":"Ica1 knockout mice with LTP/LTD electrophysiology, PSD fractionation, and behavioral memory testing","pmids":["37251649"],"confidence":"High","gaps":["Molecular basis of LTP-specific (vs LTD) requirement unresolved","How PICK1 stabilization is achieved mechanistically not shown"]},{"year":2002,"claim":"Established ICA69 as a functionally required autoantigen whose islet-autonomous expression and organ-specific T-cell responses drive autoimmune disease.","evidence":"ICA69-null NOD mice with histopathology, T-cell phenotyping, and islet vs hematopoietic transplantation epistasis","pmids":["12383988","11751995"],"confidence":"High","gaps":["Link between trafficking function and antigenicity unexplored","Mechanism of beta-cell drug toxicity dependence not molecular"]},{"year":2012,"claim":"Connected an Ica1 promoter SNP to AIRE-mediated transcriptional control, providing a mechanism for variable thymic expression.","evidence":"Luciferase reporter assays and AIRE binding affinity measurement in mTEC and B-cell lines","pmids":["22447927"],"confidence":"Medium","gaps":["Endogenous AIRE occupancy at the locus not shown","Causal in vivo test of the SNP not performed here"]},{"year":2014,"claim":"Demonstrated that thymic ICA69 expression is directly required for central tolerance, with its loss causing spontaneous multi-organ autoimmunity.","evidence":"Aire-Cre conditional ICA69 deletion with multi-organ histology and T-cell tolerance assays","pmids":["25088457"],"confidence":"High","gaps":["Why ICA69-reactive T cells damage diverse organs is unexplained","Relationship to the BAR/Rab2/PICK1 function not addressed"]},{"year":2014,"claim":"Extended the ICA69-PICK1-GluA2 axis to spinal nociception, linking the protein to inflammatory pain.","evidence":"ICA69 knockout mice with formalin pain assay, GluA2 phosphorylation/surface Western blots, and microglial immunohistochemistry","pmids":["25547463"],"confidence":"Medium","gaps":["Causality of microglial activation vs AMPAR changes unresolved","Cell-type-specific contributions not separated"]},{"year":2022,"claim":"Identified a STING-dependent pro-ferroptotic role for ICA69 in septic cardiomyopathy, broadening function beyond trafficking and tolerance.","evidence":"ICA69 knockout in LPS-induced mice with ferroptosis marker quantification and STING expression analysis","pmids":["35397620"],"confidence":"Medium","gaps":["Direct molecular link between ICA69 and STING not shown","Whether BAR/trafficking activity underlies this role is unknown"]},{"year":null,"claim":"How ICA69's BAR-domain membrane-deformation and Rab2-effector activities mechanistically connect to its disparate roles in central tolerance and STING-driven ferroptosis remains unresolved.","evidence":"","pmids":[],"confidence":"Low","gaps":["No structural model of the ICA69-PICK1 heteromeric BAR complex","No direct biochemical link between ICA69 and STING","Unclear whether the trafficking function underlies its antigenicity and tolerance roles"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0008289","term_label":"lipid binding","supporting_discovery_ids":[2,9]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[2,3]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[2]}],"localization":[{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[0,1]},{"term_id":"GO:0031410","term_label":"cytoplasmic vesicle","supporting_discovery_ids":[1,3]},{"term_id":"GO:0005794","term_label":"Golgi apparatus","supporting_discovery_ids":[3]}],"pathway":[{"term_id":"R-HSA-5653656","term_label":"Vesicle-mediated transport","supporting_discovery_ids":[3,9]},{"term_id":"R-HSA-112316","term_label":"Neuronal System","supporting_discovery_ids":[2,13]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[4,7]}],"complexes":["ICA69-PICK1 heteromeric BAR complex"],"partners":["PICK1","RAB2","PRKCA"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q05084","full_name":"Islet cell autoantigen 1","aliases":["69 kDa islet cell autoantigen","ICA69","Islet cell autoantigen p69","ICAp69","p69"],"length_aa":483,"mass_kda":54.6,"function":"May play a role in neurotransmitter secretion","subcellular_location":"Cytoplasm, cytosol; Golgi apparatus membrane; Cytoplasmic vesicle, secretory vesicle membrane; Cytoplasmic vesicle, secretory vesicle, synaptic vesicle membrane","url":"https://www.uniprot.org/uniprotkb/Q05084/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/ICA1","classification":"Not Classified","n_dependent_lines":0,"n_total_lines":1208,"dependency_fraction":0.0},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/ICA1","total_profiled":1310},"omim":[{"mim_id":"621083","title":"ISLET CELL AUTOANTIGEN 1-LIKE PROTEIN; ICA1L","url":"https://www.omim.org/entry/621083"},{"mim_id":"619250","title":"RUN DOMAIN-CONTAINING PROTEIN 1; RUNDC1","url":"https://www.omim.org/entry/619250"},{"mim_id":"147625","title":"ISLET CELL AUTOANTIGEN 1; ICA1","url":"https://www.omim.org/entry/147625"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Vesicles","reliability":"Supported"},{"location":"Cytosol","reliability":"Supported"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/ICA1"},"hgnc":{"alias_symbol":["ICAp69","ICA69"],"prev_symbol":[]},"alphafold":{"accession":"Q05084","domains":[{"cath_id":"1.20.1270.60","chopping":"68-253","consensus_level":"medium","plddt":94.6244,"start":68,"end":253}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q05084","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q05084-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q05084-F1-predicted_aligned_error_v6.png","plddt_mean":69.81},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=ICA1","jax_strain_url":"https://www.jax.org/strain/search?query=ICA1"},"sequence":{"accession":"Q05084","fasta_url":"https://rest.uniprot.org/uniprotkb/Q05084.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q05084/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q05084"}},"corpus_meta":[{"pmid":"8326004","id":"PMC_8326004","title":"Islet cell autoantigen 69 kD (ICA69). Molecular cloning and characterization of a novel diabetes-associated autoantigen.","date":"1993","source":"The Journal of clinical investigation","url":"https://pubmed.ncbi.nlm.nih.gov/8326004","citation_count":224,"is_preprint":false},{"pmid":"18032668","id":"PMC_18032668","title":"PICK1-ICA69 heteromeric BAR domain complex regulates synaptic targeting and surface expression of AMPA receptors.","date":"2007","source":"The Journal of neuroscience : the official journal of the Society for Neuroscience","url":"https://pubmed.ncbi.nlm.nih.gov/18032668","citation_count":74,"is_preprint":false},{"pmid":"35397620","id":"PMC_35397620","title":"ICA69 aggravates ferroptosis causing septic cardiac dysfunction via STING trafficking.","date":"2022","source":"Cell death discovery","url":"https://pubmed.ncbi.nlm.nih.gov/35397620","citation_count":57,"is_preprint":false},{"pmid":"7758883","id":"PMC_7758883","title":"Autoantibodies to the islet antigen ICA69 occur in IDDM and in rheumatoid 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cell","url":"https://pubmed.ncbi.nlm.nih.gov/11029035","citation_count":38,"is_preprint":false},{"pmid":"7840858","id":"PMC_7840858","title":"Sera from patients with IDDM and healthy individuals have antibodies to ICA69 on western blots but do not immunoprecipitate liquid phase antigen.","date":"1994","source":"Journal of autoimmunity","url":"https://pubmed.ncbi.nlm.nih.gov/7840858","citation_count":27,"is_preprint":false},{"pmid":"11751995","id":"PMC_11751995","title":"ICA69(null) nonobese diabetic mice develop diabetes, but resist disease acceleration by cyclophosphamide.","date":"2002","source":"Journal of immunology (Baltimore, Md. : 1950)","url":"https://pubmed.ncbi.nlm.nih.gov/11751995","citation_count":26,"is_preprint":false},{"pmid":"8777998","id":"PMC_8777998","title":"ICA69 is expressed equally in the human endocrine and exocrine 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neuroscience","url":"https://pubmed.ncbi.nlm.nih.gov/37251649","citation_count":2,"is_preprint":false},{"pmid":"38884369","id":"PMC_38884369","title":"ICA1 affects APP processing through the PICK1-PKCα signaling pathway.","date":"2024","source":"CNS neuroscience & therapeutics","url":"https://pubmed.ncbi.nlm.nih.gov/38884369","citation_count":2,"is_preprint":false},{"pmid":"6578583","id":"PMC_6578583","title":"Clinical studies on ionized calcium using the radiometer ICA1 analyzer.","date":"1983","source":"Scandinavian journal of clinical and laboratory investigation. Supplementum","url":"https://pubmed.ncbi.nlm.nih.gov/6578583","citation_count":2,"is_preprint":false},{"pmid":"2102778","id":"PMC_2102778","title":"Modelling of type 1 diabetes with monoclonal antibody ICA-1.","date":"1990","source":"Biomedical science","url":"https://pubmed.ncbi.nlm.nih.gov/2102778","citation_count":2,"is_preprint":false},{"pmid":"2130918","id":"PMC_2130918","title":"Immunoreactivity of cultured pancreatic islet cells with monoclonal antibody ICA-1.","date":"1990","source":"Biomedical science","url":"https://pubmed.ncbi.nlm.nih.gov/2130918","citation_count":1,"is_preprint":false},{"pmid":"2673809","id":"PMC_2673809","title":"Pancreatic islet cells in tissue culture: function and immunoreactivity with serum autoantibodies from diabetes type-1 patients and monoclonal antibodies ICA-1.","date":"1989","source":"Experimental and clinical endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/2673809","citation_count":1,"is_preprint":false},{"pmid":"6578572","id":"PMC_6578572","title":"An evaluation of the ICA1 ionized calcium analyzer in a clinical chemistry laboratory.","date":"1983","source":"Scandinavian journal of clinical and laboratory investigation. 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Deletion of ric-19 in C. elegans causes aldicarb resistance (defective neurotransmitter secretion), rescued by ric-19 transgene.\",\n      \"method\": \"Subcellular fractionation, immunostaining, C. elegans deletion mutant with aldicarb resistance assay, transgenic rescue\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (fractionation, localization, genetic loss-of-function, transgenic rescue) across two organisms, replicated concept\",\n      \"pmids\": [\"11029035\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"ICA69 is the major binding partner of PICK1 in the brain (>75% of each protein associates with the other); the BAR domain of ICA69 forms heteromeric BAR domain complexes with PICK1 and binds liposomes. ICA69 overexpression redistributes PICK1 from synapses to dendrites, disrupts PICK1-induced AMPA receptor clustering, and reduces synaptic targeting and surface expression of AMPA receptors, indicating that the switch between ICA69-PICK1 heteromers and PICK1 homomers regulates AMPAR trafficking.\",\n      \"method\": \"Co-immunoprecipitation, liposome-binding assay, overexpression in neurons, immunofluorescence colocalization, surface AMPAR quantification\",\n      \"journal\": \"The Journal of neuroscience\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP from brain, liposome binding, functional overexpression with defined AMPAR phenotype, multiple orthogonal methods in one study\",\n      \"pmids\": [\"18032668\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"ICA69 is a novel Rab2 effector: it binds to Rab2 in a GTP-dependent manner, and Rab2 recruits ICA69 to membranes. Over-expression of either Rab2 or ICA69 in insulinoma INS-1 cells impairs anterograde transport of secretory granule protein precursors (pro-ICA512, chromogranin A) and reduces stimulated insulin secretion, placing ICA69 in ER-Golgi COPI vesicle transport.\",\n      \"method\": \"Co-immunoprecipitation (GTP-dependent), membrane recruitment assay, overexpression in INS-1 cells, pulse-chase secretory granule trafficking assay, insulin secretion assay\",\n      \"journal\": \"European journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — GTP-dependent binding with Co-IP, functional trafficking and secretion assays with multiple readouts, single lab but multiple orthogonal methods\",\n      \"pmids\": [\"18187231\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"Genetic disruption of the ICA69 locus in NOD mice prevents lacrimal gland autoimmune disease and greatly reduces salivary gland disease; ICA69-specific T cells accumulate in lymph nodes draining salivary tissue in healthy NOD mice, establishing ICA69 as a functionally required autoantigen in Sjögren's syndrome progression.\",\n      \"method\": \"Genomic knockout (ICA69-null NOD congenic mice), histopathological assessment, T-cell immunophenotyping, peptide immunotherapy\",\n      \"journal\": \"Lancet\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean genetic knockout with defined organ-specific disease phenotype, multiple immunological readouts, replicated in multiple NOD cohorts\",\n      \"pmids\": [\"12383988\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"ICA69-null NOD mice develop spontaneous diabetes and insulitis normally but are resistant to cyclophosphamide-accelerated diabetes; transplantation experiments linked this resistance to ICA69 deficiency specifically in islets (not in the hematopoietic compartment), indicating ICA69-dependent beta-cell drug toxicity contributes to CY-accelerated autoimmunity.\",\n      \"method\": \"ICA69 knockout mice, cyclophosphamide treatment, islet and hematopoietic tissue transplantation, diabetes incidence assay\",\n      \"journal\": \"Journal of immunology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic knockout with tissue-specific transplantation epistasis experiments defining islet-autonomous function\",\n      \"pmids\": [\"11751995\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"The C-terminal domain of ICA69 (ICAC) interacts with PICK1 and inhibits PKCα-mediated trafficking of the PICK1-PKCα complex to the plasma membrane; overexpression of ICAC (but not the BAR domain alone) blocks this trafficking. Infusion of MBP-ICA69 or MBP-ICAC into cerebellar Purkinje cells inhibits induction of long-term depression at parallel fiber and climbing fiber synapses.\",\n      \"method\": \"Co-immunoprecipitation, overexpression of domain deletion constructs, fluorescence imaging of PICK1-PKCα trafficking, intracellular protein infusion with electrophysiological LTD recording\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — domain mapping with Co-IP and trafficking assay, functional LTD recording, single lab\",\n      \"pmids\": [\"24358315\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Thymic-specific deletion of ICA69 (Aire-ΔICA69 mice) causes suboptimal central negative selection of ICA69-reactive T cells and spontaneous multi-organ autoimmunity (pancreas, salivary glands, thyroid, stomach), establishing a direct causal link between thymic ICA69 expression and maintenance of peripheral self-tolerance.\",\n      \"method\": \"Tissue-specific conditional knockout (Aire-Cre driven), histological analysis of organ inflammation, T-cell tolerance assays\",\n      \"journal\": \"Journal of autoimmunity\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — conditional genetic knockout with defined multi-organ phenotype and mechanistic link to central tolerance, multiple orthogonal readouts\",\n      \"pmids\": [\"25088457\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Loss of ICA69 in mice reduces PICK1 protein levels in spinal cord, increases Ser880 phosphorylation of GluA2 and decreases surface GluA2 expression, leading to enhanced inflammatory pain hypersensitivity after formalin injection; microglial activation in the spinal dorsal horn was also increased.\",\n      \"method\": \"ICA69 knockout mice, formalin pain assay, Western blotting for GluA2 phosphorylation and surface expression, immunohistochemistry for microglial activation\",\n      \"journal\": \"Neurochemical research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic KO with defined pain phenotype and biochemical AMPAR readouts, single lab, multiple methods\",\n      \"pmids\": [\"25547463\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"In Drosophila, ICA69 colocalizes with α-Spectrin at the neuromuscular junction (NMJ); the N-BAR domain deforms liposomes in vitro; full-length ICA69 and ICAC (but not N-BAR alone) induce filopodia in cultured cells. ICA69 mutants show reduced α-Spectrin at the NMJ and altered synaptic glutamate receptor levels. Reducing PICK1 or Rab2 phenocopies ICA69 mutation, and Rab2 functions genetically upstream of ICA69 regulating ICA69 levels and NMJ organization.\",\n      \"method\": \"RNAi screen, genetic loss-of-function, liposome deformation assay, immunofluorescence colocalization, filopodia induction assay, epistasis analysis\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — in vitro BAR domain membrane-deformation assay plus genetic epistasis defining pathway order (Rab2→ICA69→PICK1) plus multiple cellular phenotype readouts\",\n      \"pmids\": [\"28455372\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"A single nucleotide polymorphism in the NOD mouse Ica1 promoter increases binding affinity for the transcription factor AIRE, which down-regulates ICA69 expression in medullary thymic epithelial cells; luciferase reporter assays showed NOD Ica1 promoter drives markedly reduced expression compared to C57BL/6 in mTEC and B-cell lines.\",\n      \"method\": \"Luciferase reporter assays, AIRE binding affinity assay, SNP identification, transfection in mTEC and B-cell lines\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reporter assays and direct TF binding measurement, single lab, mechanistically links promoter SNP to AIRE-mediated transcriptional regulation\",\n      \"pmids\": [\"22447927\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"The ICA1 gene uses alternative core promoters in a tissue-specific manner: the exon A promoter is more active in islet cells and the exon B promoter in neuronal cells; a CREB site within the exon B promoter negatively regulates transcriptional activity in both cell types.\",\n      \"method\": \"5'-RACE, luciferase reporter constructs, CREB site mutagenesis, transient transfection in islet (RIN) and neuronal (NMB7) cell lines\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reporter assays with site-directed mutagenesis confirming CREB site function, single lab, multiple cell lines\",\n      \"pmids\": [\"12409289\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"ICA69 promotes ferroptosis in LPS-treated cardiomyocytes and macrophages by triggering STING production, which drives intracellular lipid peroxidation. ICA69 knockout in LPS-induced mice elevated survival and heart function, reduced ferroptosis markers (PTGS2, MDA, 4HNE, GPX4, SOD, iron, lipid ROS), and reduced inflammatory cytokines, but had no effect on xCT-dependent pathways.\",\n      \"method\": \"ICA69 knockout mice, LPS-induced septic cardiomyopathy model, ferroptosis marker quantification (ELISA, Western blot), STING expression analysis\",\n      \"journal\": \"Cell death discovery\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic KO with defined ferroptosis phenotype and mechanistic STING link, single lab, multiple biochemical readouts\",\n      \"pmids\": [\"35397620\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"ICA69 regulates PICK1 protein stability and distribution in the hippocampus. Genetic deletion of ICA69 (Ica1 knockout) selectively impairs NMDAR-dependent LTP but not LTD at Schaffer collateral–CA1 synapses without affecting basal AMPAR-mediated currents, dendritic morphology, or PSD AMPAR levels; this correlates with deficits in spatial and associative learning and memory.\",\n      \"method\": \"Ica1 knockout mice, electrophysiological LTP/LTD recording, PSD biochemical fractionation, Western blotting, behavioral tests (spatial and associative memory)\",\n      \"journal\": \"Frontiers in molecular neuroscience\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic KO with electrophysiological LTP specificity, biochemical fractionation, and behavioral readouts; multiple orthogonal methods in single study\",\n      \"pmids\": [\"37251649\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"ICA1/ICA69 overexpression increases APP, ADAM10, and ADAM17 protein levels and increases PKCα protein levels and phosphorylation, shifting APP processing toward non-amyloidogenic pathways via the PICK1-PKCα signaling axis; transcriptome analysis indicated ICA1 regulates G protein-coupled receptor signaling.\",\n      \"method\": \"Overexpression in cell lines, Western blotting for APP/ADAM10/ADAM17/PKCα, transcriptome sequencing, half-life and mRNA level analysis\",\n      \"journal\": \"CNS neuroscience & therapeutics\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, overexpression-based, no rescue or mutagenesis; pathway assignment inferred from transcriptomics and protein levels without direct mechanistic reconstitution\",\n      \"pmids\": [\"38884369\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"ICA69 (encoded by ICA1) is a BAR-domain-containing cytosolic protein that associates with secretory vesicles and the Golgi, acts as a GTP-dependent effector of Rab2 to regulate ER-Golgi trafficking and insulin secretory granule biogenesis, and in neurons forms heteromeric BAR complexes with PICK1 to control AMPA receptor trafficking, synaptic plasticity (selectively required for LTP), and learning and memory; it also modulates ferroptosis via STING in cardiomyocytes, and its expression level in the thymus—regulated by AIRE through promoter polymorphisms—controls central tolerance to prevent multi-organ autoimmunity.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"ICA1 encodes ICA69, a conserved BAR-domain cytosolic protein that links membrane deformation to regulated secretion in both neuroendocrine and neuronal cells [#0, #1]. A subpopulation associates with synaptic vesicles and synaptic-like microvesicles, and its loss in the C. elegans ortholog RIC-19 impairs neurotransmitter secretion [#1]. Mechanistically, ICA69 acts as a GTP-dependent effector of Rab2: Rab2 recruits it to membranes and positions it within ER-Golgi COPI vesicle transport, where it is required for anterograde delivery of secretory granule precursors (pro-ICA512, chromogranin A) and stimulated insulin secretion [#3]. Its N-BAR domain binds and deforms liposomes and induces filopodia, and genetic epistasis places it in a Rab2\\u2192ICA69\\u2192PICK1 pathway controlling synaptic architecture [#9]. In neurons, ICA69 is the major brain partner of PICK1, forming heteromeric BAR complexes whose balance against PICK1 homomers governs AMPA receptor clustering, surface expression, and trafficking [#2]; through this PICK1 axis it stabilizes PICK1 protein and is selectively required for NMDAR-dependent LTP and for spatial and associative memory [#13]. Independently, thymic ICA69 expression \\u2014 set by AIRE acting on the Ica1 promoter \\u2014 drives central negative selection of ICA69-reactive T cells, and its loss causes spontaneous multi-organ autoimmunity, establishing ICA69 as a tolerance-controlling autoantigen [#7, #10]. ICA69 also promotes STING-driven ferroptosis in cardiomyocytes during endotoxemia [#12].\",\n  \"teleology\": [\n    {\n      \"year\": 1993,\n      \"claim\": \"Established that ICA1 encodes a discrete 69 kDa protein (ICA69) and defined its tissue distribution, providing the molecular entity to study in beta cells and brain.\",\n      \"evidence\": \"cDNA library screening with Northern, Western, and SDS-PAGE characterization\",\n      \"pmids\": [\"8326004\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No function assigned at this stage\", \"Subcellular localization and binding partners unknown\"]\n    },\n    {\n      \"year\": 2000,\n      \"claim\": \"Showed ICA69 is a conserved membrane-associated regulator of neuroendocrine secretion, moving it from an antigen to a vesicle-trafficking protein.\",\n      \"evidence\": \"Subcellular fractionation and immunostaining in mouse, plus C. elegans ric-19 deletion (aldicarb resistance) with transgenic rescue\",\n      \"pmids\": [\"11029035\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular partners and the membrane-binding mechanism not yet defined\", \"Direct biochemical role in vesicle budding unresolved\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Identified PICK1 as the dominant brain partner and defined ICA69-PICK1 heteromeric BAR complexes as a switch controlling AMPA receptor trafficking.\",\n      \"evidence\": \"Reciprocal Co-IP from brain, liposome binding, and neuronal overexpression with surface AMPAR quantification\",\n      \"pmids\": [\"18032668\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Effect shown by overexpression rather than endogenous loss-of-function\", \"In vivo synaptic consequence not yet tested\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Defined ICA69 as a GTP-dependent Rab2 effector required for ER-Golgi anterograde transport and insulin secretion, giving its trafficking role a molecular mechanism.\",\n      \"evidence\": \"GTP-dependent Co-IP, membrane recruitment, and pulse-chase secretory granule trafficking plus insulin secretion assays in INS-1 cells\",\n      \"pmids\": [\"18187231\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct demonstration of BAR-mediated membrane curvature in this pathway not shown\", \"Relationship between Rab2 and PICK1 functions unaddressed here\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Ordered the pathway genetically (Rab2\\u2192ICA69\\u2192PICK1) and demonstrated direct N-BAR membrane deformation, unifying the trafficking and synaptic roles.\",\n      \"evidence\": \"Drosophila RNAi/genetic loss-of-function, liposome deformation, filopodia induction, and epistasis at the NMJ\",\n      \"pmids\": [\"28455372\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of heteromeric BAR assembly not resolved\", \"Conservation of epistasis order in mammals not directly tested\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Mapped the C-terminal domain as the PICK1-interacting/PKC\\u03b1-regulating module and linked ICA69 to cerebellar LTD induction.\",\n      \"evidence\": \"Domain-deletion Co-IP, PICK1-PKC\\u03b1 trafficking imaging, and protein infusion with LTD electrophysiology in Purkinje cells\",\n      \"pmids\": [\"24358315\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Acute infusion/overexpression rather than genetic loss\", \"Endogenous requirement for LTD not established\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Defined the in vivo synaptic function: ICA69 stabilizes PICK1 and is selectively required for NMDAR-dependent LTP and for learning and memory.\",\n      \"evidence\": \"Ica1 knockout mice with LTP/LTD electrophysiology, PSD fractionation, and behavioral memory testing\",\n      \"pmids\": [\"37251649\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular basis of LTP-specific (vs LTD) requirement unresolved\", \"How PICK1 stabilization is achieved mechanistically not shown\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Established ICA69 as a functionally required autoantigen whose islet-autonomous expression and organ-specific T-cell responses drive autoimmune disease.\",\n      \"evidence\": \"ICA69-null NOD mice with histopathology, T-cell phenotyping, and islet vs hematopoietic transplantation epistasis\",\n      \"pmids\": [\"12383988\", \"11751995\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Link between trafficking function and antigenicity unexplored\", \"Mechanism of beta-cell drug toxicity dependence not molecular\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Connected an Ica1 promoter SNP to AIRE-mediated transcriptional control, providing a mechanism for variable thymic expression.\",\n      \"evidence\": \"Luciferase reporter assays and AIRE binding affinity measurement in mTEC and B-cell lines\",\n      \"pmids\": [\"22447927\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Endogenous AIRE occupancy at the locus not shown\", \"Causal in vivo test of the SNP not performed here\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Demonstrated that thymic ICA69 expression is directly required for central tolerance, with its loss causing spontaneous multi-organ autoimmunity.\",\n      \"evidence\": \"Aire-Cre conditional ICA69 deletion with multi-organ histology and T-cell tolerance assays\",\n      \"pmids\": [\"25088457\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Why ICA69-reactive T cells damage diverse organs is unexplained\", \"Relationship to the BAR/Rab2/PICK1 function not addressed\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Extended the ICA69-PICK1-GluA2 axis to spinal nociception, linking the protein to inflammatory pain.\",\n      \"evidence\": \"ICA69 knockout mice with formalin pain assay, GluA2 phosphorylation/surface Western blots, and microglial immunohistochemistry\",\n      \"pmids\": [\"25547463\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Causality of microglial activation vs AMPAR changes unresolved\", \"Cell-type-specific contributions not separated\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Identified a STING-dependent pro-ferroptotic role for ICA69 in septic cardiomyopathy, broadening function beyond trafficking and tolerance.\",\n      \"evidence\": \"ICA69 knockout in LPS-induced mice with ferroptosis marker quantification and STING expression analysis\",\n      \"pmids\": [\"35397620\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct molecular link between ICA69 and STING not shown\", \"Whether BAR/trafficking activity underlies this role is unknown\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How ICA69's BAR-domain membrane-deformation and Rab2-effector activities mechanistically connect to its disparate roles in central tolerance and STING-driven ferroptosis remains unresolved.\",\n      \"evidence\": null,\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No structural model of the ICA69-PICK1 heteromeric BAR complex\", \"No direct biochemical link between ICA69 and STING\", \"Unclear whether the trafficking function underlies its antigenicity and tolerance roles\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0008289\", \"supporting_discovery_ids\": [2, 9]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [2, 3]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [2]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [0, 1]},\n      {\"term_id\": \"GO:0031410\", \"supporting_discovery_ids\": [1, 3]},\n      {\"term_id\": \"GO:0005794\", \"supporting_discovery_ids\": [3]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-5653656\", \"supporting_discovery_ids\": [3, 9]},\n      {\"term_id\": \"R-HSA-112316\", \"supporting_discovery_ids\": [2, 13]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [4, 7]}\n    ],\n    \"complexes\": [\n      \"ICA69-PICK1 heteromeric BAR complex\"\n    ],\n    \"partners\": [\n      \"PICK1\",\n      \"RAB2\",\n      \"PRKCA\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"faith_supported":6,"faith_total":7,"faith_pct":85.71428571428571}}