{"gene":"MCCC1","run_date":"2026-04-28T18:30:28","timeline":{"discoveries":[{"year":2001,"finding":"The human MCCC1 (MCCA) gene encodes the 725-amino-acid biotin-containing alpha-subunit of 3-methylcrotonyl-CoA carboxylase (MCC), a mitochondrial enzyme involved in leucine catabolism. The MCCA cDNA was cloned, the gene mapped to chromosome 3q26-q28 with 19 exons, and mutations (S535F, V694X compound heterozygosity) in MCCA were correlated with near-total loss of MCC enzyme activity in patient fibroblasts, establishing MCCA as causative for 3-methylcrotonyl-CoA carboxylase deficiency.","method":"cDNA cloning, chromosomal mapping, patient mutation sequencing, fibroblast enzyme activity assay","journal":"Human molecular genetics","confidence":"High","confidence_rationale":"Tier 1-2 — direct cloning, gene characterization, and mutation-to-enzyme activity correlation in patient-derived cells; replicated in a second independent paper (PMID:11401427)","pmids":["11406611","11401427"],"is_preprint":false},{"year":2001,"finding":"MCCC1 (MCCA) protein contains mitochondrial signal peptide, biotin carboxylase, and biotin-carrier protein domains. The gene is abundantly expressed in mitochondria-rich organs (heart, skeletal muscle, kidney, liver), consistent with its mitochondrial enzymatic role in leucine and isovalerate catabolism.","method":"cDNA sequence analysis, northern blot/expression profiling, chromosomal mapping","journal":"Genomics","confidence":"Medium","confidence_rationale":"Tier 2 — direct sequence characterization with domain identification and expression data; single lab","pmids":["11401427"],"is_preprint":false},{"year":2003,"finding":"Four missense mutations in MCCA (two) and MCCB (two), mapped to evolutionarily conserved residues, were expressed by transient transfection in MCC-deficient fibroblasts and all resulted in null or severely diminished MCC carboxylase activity, directly confirming their pathogenicity. Structural modelling of MCCA mutations in the context of the E. coli acetyl-CoA carboxylase biotin carboxylase subunit crystal structure provided mechanistic explanation for loss of function.","method":"Transient transfection in deficient fibroblasts, enzyme activity assay, 3D structural modelling","journal":"Molecular genetics and metabolism","confidence":"High","confidence_rationale":"Tier 1-2 — functional reconstitution in deficient cells with enzyme activity readout plus structural modelling; multiple mutations tested","pmids":["14680978"],"is_preprint":false},{"year":2012,"finding":"Crystal structures of the MCC holoenzyme (containing the MCCC1/alpha subunit) revealed an unanticipated architecture with previously unrecognized domains and provided a molecular basis for understanding the catalytic mechanism of biotin-dependent carboxylation in leucine catabolism, as well as explaining disease-causing mutations.","method":"Crystal structure determination of MCC holoenzyme","journal":"Cellular and molecular life sciences : CMLS","confidence":"High","confidence_rationale":"Tier 1 — structural determination with functional interpretation; comprehensive review of MCC holoenzyme structure","pmids":["22869039"],"is_preprint":false},{"year":2023,"finding":"MCCC1 (MCCA) physically interacts with the pro-apoptotic protein Bad in multiple myeloma cells, as demonstrated by immunoprecipitation and immunofluorescence. MCCC1 knockdown shortened the half-life of Bad (from 7.34 to 2.42 h) and shifted the apoptotic balance toward anti-apoptotic proteins (increased Bcl-xl and Mcl-1, decreased Bax and Bad), leading to multidrug resistance and mitochondrial dysfunction.","method":"Immunoprecipitation, immunofluorescence, protein structural simulation, CCK-8 viability assay, apoptosis assay, in vivo xenograft model","journal":"Life sciences","confidence":"Medium","confidence_rationale":"Tier 2 — Co-IP plus functional KD with defined cellular phenotype; single lab, multiple orthogonal methods","pmids":["37805164"],"is_preprint":false},{"year":2021,"finding":"lncRNA AABR07005593.1, upregulated by PM2.5 exposure, was shown by ChIRP-MS and western blot to interact physically with MCCC1 protein, and this interaction was required for activation of the NF-κB pathway and downstream IL-6 expression in rat alveolar macrophages.","method":"ChIRP-MS, western blot, RNA interference, in vivo rat inflammation model","journal":"Ecotoxicology and environmental safety","confidence":"Medium","confidence_rationale":"Tier 2-3 — ChIRP-MS identification of MCCC1 as lncRNA binding partner with functional RNAi follow-up; single lab","pmids":["34619471"],"is_preprint":false},{"year":2025,"finding":"The lncRNA lncBADR binds directly to Mccc1 (and Pcca) in T cells, inhibiting branched-chain amino acid (BCAA) degradation. This leads to intracellular BCAA accumulation, mTOR-Stat1 pathway activation, and increased IFN-γ secretion promoting autoimmune encephalomyelitis. T cell-specific lncBADR knockout restored BCAA degradation and reduced pathogenic T cell function.","method":"T cell-specific knockout mouse model (EAE), RNA-protein binding assay, metabolic assays, mTOR-Stat1 pathway analysis, high-BCAAs feeding rescue experiment","journal":"Journal of neuroinflammation","confidence":"Medium","confidence_rationale":"Tier 2 — genetic KO with defined metabolic and immunological phenotype plus rescue experiment; single lab","pmids":["41013574"],"is_preprint":false},{"year":2024,"finding":"Corosolic acid (CA) and its derivative H26 directly bind to MCCC1, identified by avidin-biotin affinity pull-down with CA-biotin chemical probe followed by quantitative proteomics. This interaction was confirmed in vitro, and MCCC1 was identified as a target in the insulin resistance signaling pathway, with CA/H26 showing hypoglycemic effects in type 2 diabetic mice.","method":"Avidin-biotin affinity pull-down, quantitative proteomics, in vitro binding assay, T2DM mouse model","journal":"European journal of medicinal chemistry","confidence":"Medium","confidence_rationale":"Tier 2-3 — chemical probe-based target identification with in vitro confirmation and in vivo phenotype; single lab","pmids":["39731787"],"is_preprint":false},{"year":2025,"finding":"The intronic PD-risk variant rs12637471 in MCCC1 regulates MCCC1 mRNA expression: G-allele carriers show significantly elevated MCCC1 mRNA in postmortem brain tissue (consistent with GTEx eQTL data), and CRISPR/Cas9-edited isogenic iPSC-derived dopaminergic neurons carrying the G-allele show increased MCCC1 expression, implicating MCCC1 dysregulation in mitochondrial homeostasis or inflammation relevant to Parkinson's disease.","method":"Postmortem brain RNA analysis, CRISPR/Cas9 isogenic iPSC line generation, iPSC differentiation to dopaminergic neurons, mRNA quantification","journal":"Journal of human genetics","confidence":"Medium","confidence_rationale":"Tier 2 — CRISPR isogenic system with neuronal differentiation and expression readout; single lab, moderate mechanistic depth","pmids":["40216992"],"is_preprint":false}],"current_model":"MCCC1 encodes the biotin-containing alpha-subunit of the mitochondrial heteromeric enzyme 3-methylcrotonyl-CoA carboxylase (MCC), which catalyzes a critical step in leucine catabolism; loss-of-function mutations cause MCC deficiency, the holoenzyme structure has been determined by crystallography revealing the catalytic mechanism, and MCCC1 additionally interacts with the pro-apoptotic protein Bad to regulate mitochondrial apoptotic signaling in cancer cells, is bound by lncRNAs (lncBADR, AABR07005593.1) that inhibit its BCAA-degrading activity or modulate NF-κB-driven inflammation, and is directly targeted by corosolic acid in the insulin resistance pathway."},"narrative":{"teleology":[{"year":2001,"claim":"Cloning of MCCC1 established the molecular identity of the biotin-containing alpha subunit of MCC and linked mutations directly to loss of enzyme activity, resolving the genetic basis of MCC deficiency.","evidence":"cDNA cloning, chromosomal mapping, and enzyme activity assays in patient fibroblasts carrying compound heterozygous mutations","pmids":["11406611","11401427"],"confidence":"High","gaps":["Three-dimensional structure of the holoenzyme not yet determined","Spectrum of pathogenic alleles and genotype-phenotype correlations incomplete","No reconstitution of purified recombinant holoenzyme to measure kinetics"]},{"year":2003,"claim":"Functional expression of disease-associated missense mutations in MCC-deficient fibroblasts confirmed their pathogenicity by demonstrating null or severely reduced carboxylase activity, validating the causal link between specific MCCC1 residues and catalytic function.","evidence":"Transient transfection rescue in deficient fibroblasts with enzyme activity measurement and structural modelling against the E. coli biotin carboxylase crystal structure","pmids":["14680978"],"confidence":"High","gaps":["Structural modelling relied on a bacterial homolog rather than the human MCC structure","Mechanism of substrate specificity for methylcrotonyl-CoA not addressed"]},{"year":2012,"claim":"Crystal structure determination of the MCC holoenzyme revealed an unexpected architecture with previously unrecognized domains, providing the first atomic-level explanation for the catalytic mechanism and for how disease mutations disrupt function.","evidence":"X-ray crystallography of the MCC holoenzyme complex","pmids":["22869039"],"confidence":"High","gaps":["Dynamics of biotin translocation between catalytic sites not captured by static structure","No co-crystal with the methylcrotonyl-CoA substrate reported"]},{"year":2021,"claim":"Identification of lncRNA AABR07005593.1 as a physical binding partner of MCCC1 revealed an unexpected role for the enzyme in NF-κB pathway activation and inflammatory cytokine production, extending MCCC1 function beyond leucine catabolism.","evidence":"ChIRP-MS target identification with RNAi validation in rat alveolar macrophages and an in vivo PM2.5 inflammation model","pmids":["34619471"],"confidence":"Medium","gaps":["Mechanism by which MCCC1–lncRNA interaction activates NF-κB is undefined","Single lab finding in a rat system without human cell validation","Unclear whether the catalytic activity of MCCC1 is required for this non-metabolic role"]},{"year":2023,"claim":"Discovery that MCCC1 physically interacts with and stabilizes Bad in multiple myeloma cells established a non-canonical role for MCCC1 in mitochondrial apoptotic signaling and drug resistance.","evidence":"Co-immunoprecipitation, immunofluorescence, protein half-life assays, and xenograft models in multiple myeloma cells","pmids":["37805164"],"confidence":"Medium","gaps":["Binding domain on MCCC1 responsible for Bad interaction not mapped","Whether this interaction occurs in non-cancer cells is untested","No reciprocal rescue experiment to confirm specificity"]},{"year":2024,"claim":"Chemical probe-based target identification showed corosolic acid directly binds MCCC1, implicating the enzyme in insulin resistance signaling and suggesting it as a druggable target for glucose homeostasis.","evidence":"Avidin-biotin affinity pull-down with quantitative proteomics and in vitro binding confirmation; hypoglycemic effects in T2DM mice","pmids":["39731787"],"confidence":"Medium","gaps":["Binding site of corosolic acid on MCCC1 not determined","Whether binding modulates carboxylase activity or a non-enzymatic function is unknown","Single lab; no genetic validation (e.g., MCCC1 KO rescue) provided"]},{"year":2025,"claim":"lncBADR was shown to bind MCCC1 in T cells and inhibit BCAA degradation, causing intracellular BCAA accumulation that drives mTOR-Stat1-IFN-γ signaling and autoimmune pathology, connecting MCCC1's metabolic activity to adaptive immune regulation.","evidence":"T cell-specific lncBADR knockout mice with EAE model, RNA-protein binding assays, metabolic flux measurements, and dietary BCAA rescue","pmids":["41013574"],"confidence":"Medium","gaps":["Binding interface between lncBADR and MCCC1 not characterized","Whether the effect is specific to MCCC1 or also mediated through concurrent Pcca binding is not resolved"]},{"year":2025,"claim":"A PD-risk intronic variant (rs12637471) was shown to regulate MCCC1 expression in dopaminergic neurons using CRISPR-edited isogenic iPSCs, linking MCCC1 dysregulation to Parkinson's disease susceptibility.","evidence":"Postmortem brain mRNA analysis and CRISPR/Cas9 isogenic iPSC-derived dopaminergic neuron differentiation with expression quantification","pmids":["40216992"],"confidence":"Medium","gaps":["Downstream functional consequences of elevated MCCC1 in neurons not characterized","No direct link to neurodegeneration phenotype beyond expression change","Single lab; needs replication and phenotypic readout (e.g., mitochondrial function, survival)"]},{"year":null,"claim":"How MCCC1's non-enzymatic interactions (with Bad, lncRNAs, and small molecules) relate to its canonical carboxylase activity, and whether catalytic and signaling roles are independent or coupled, remains unresolved.","evidence":"","pmids":[],"confidence":"Low","gaps":["No mutagenesis studies separating catalytic from protein-interaction functions","Structural basis of MCCC1 interaction with Bad and lncRNAs unknown","Tissue-specific non-metabolic roles not systematically assessed"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016874","term_label":"ligase activity","supporting_discovery_ids":[0,2,3]},{"term_id":"GO:0140657","term_label":"ATP-dependent activity","supporting_discovery_ids":[0,3]}],"localization":[{"term_id":"GO:0005739","term_label":"mitochondrion","supporting_discovery_ids":[0,1,4]}],"pathway":[{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[0,1,2,3,6]}],"complexes":["3-methylcrotonyl-CoA carboxylase (MCC holoenzyme)"],"partners":["MCCC2","BAD"],"other_free_text":[]},"mechanistic_narrative":"MCCC1 encodes the biotin-containing alpha subunit of the mitochondrial 3-methylcrotonyl-CoA carboxylase (MCC) holoenzyme, which catalyzes a biotin-dependent carboxylation step essential for leucine catabolism. The protein harbors a mitochondrial targeting signal, a biotin carboxylase domain, and a biotin-carrier protein domain, and is highly expressed in mitochondria-rich tissues such as heart, skeletal muscle, kidney, and liver [PMID:11406611, PMID:11401427]. Loss-of-function mutations in MCCC1 abolish MCC enzyme activity and cause 3-methylcrotonyl-CoA carboxylase deficiency, a Mendelian organic aciduria, with the crystal structure of the holoenzyme providing a molecular framework for understanding pathogenic variants [PMID:14680978, PMID:22869039]. Beyond its metabolic role, MCCC1 physically interacts with the pro-apoptotic protein Bad to stabilize it and regulate mitochondrial apoptotic signaling, and serves as a direct binding target of regulatory lncRNAs (lncBADR, AABR07005593.1) that modulate BCAA degradation and NF-κB-driven inflammation [PMID:37805164, PMID:41013574, PMID:34619471]."},"prefetch_data":{"uniprot":{"accession":"Q96RQ3","full_name":"Methylcrotonoyl-CoA carboxylase subunit alpha, mitochondrial","aliases":["3-methylcrotonyl-CoA carboxylase 1","3-methylcrotonyl-CoA carboxylase biotin-containing subunit","3-methylcrotonyl-CoA:carbon dioxide ligase subunit alpha"],"length_aa":725,"mass_kda":80.5,"function":"Biotin-attachment subunit of the 3-methylcrotonyl-CoA carboxylase, an enzyme that catalyzes the conversion of 3-methylcrotonyl-CoA to 3-methylglutaconyl-CoA, a critical step for leucine and isovaleric acid catabolism","subcellular_location":"Mitochondrion 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all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/MCCC1"},"hgnc":{"alias_symbol":["MCCA","MCCCα"],"prev_symbol":[]},"alphafold":{"accession":"Q96RQ3","domains":[{"cath_id":"3.40.50.20","chopping":"50-150","consensus_level":"high","plddt":97.0419,"start":50,"end":150},{"cath_id":"3.30.1490.20","chopping":"179-247","consensus_level":"high","plddt":88.2678,"start":179,"end":247},{"cath_id":"3.30.470.20","chopping":"259-495","consensus_level":"medium","plddt":95.6658,"start":259,"end":495},{"cath_id":"3.30.700.40","chopping":"504-635","consensus_level":"high","plddt":91.4678,"start":504,"end":635},{"cath_id":"2.40.50.100","chopping":"649-713","consensus_level":"high","plddt":86.9742,"start":649,"end":713}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q96RQ3","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q96RQ3-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q96RQ3-F1-predicted_aligned_error_v6.png","plddt_mean":87.62},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=MCCC1","jax_strain_url":"https://www.jax.org/strain/search?query=MCCC1"},"sequence":{"accession":"Q96RQ3","fasta_url":"https://rest.uniprot.org/uniprotkb/Q96RQ3.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q96RQ3/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q96RQ3"}},"corpus_meta":[{"pmid":"23108278","id":"PMC_23108278","title":"Three-way 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The cDNA was cloned, the gene mapped to chromosome 3q27, shown to comprise at least 19 exons, and mutations in MCCA were demonstrated to cause near-total loss of MCC enzyme activity in patient fibroblasts.\",\n      \"method\": \"cDNA cloning, chromosomal mapping, patient mutation sequencing, fibroblast enzyme activity assay\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — cloning with direct enzyme activity measurement in patient fibroblasts, replicated across two independent papers in the same year\",\n      \"pmids\": [\"11406611\", \"11401427\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"Missense mutations in MCCA (MCCC1) mapping to evolutionarily conserved residues result in null or severely diminished MCC carboxylase activity when expressed by transient transfection in SV40-transformed deficient fibroblasts; structural modeling in the context of the E. coli acetyl-CoA carboxylase biotin carboxylase subunit provided mechanistic context for their pathogenicity.\",\n      \"method\": \"Transient transfection of patient-derived fibroblasts, enzyme activity assay, 3D structural modeling\",\n      \"journal\": \"Molecular genetics and metabolism\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — functional reconstitution in cells with direct enzyme activity readout plus structural modeling\",\n      \"pmids\": [\"14680978\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"lncRNA AABR07005593.1 physically interacts with MCCC1 protein and, through this interaction, activates the NF-κB pathway to promote IL-6 expression in PM2.5-exposed macrophages.\",\n      \"method\": \"ChIRP-MS (comprehensive identification of RNA-binding proteins by mass spectrometry), western blot, RNA interference knockdown\",\n      \"journal\": \"Ecotoxicology and environmental safety\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — ChIRP-MS identifies interaction, supported by western blot and RNAi functional follow-up in a single study\",\n      \"pmids\": [\"34619471\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"MCCC1 (MCCA) protein physically interacts with the pro-apoptotic protein Bad; MCCC1 knockdown in multiple myeloma cells shortened Bad's half-life, reduced Bax and Bad levels, increased Bcl-xl and Mcl-1 levels, and resulted in dysfunctional mitochondria and enhanced multidrug resistance, establishing a role for MCCC1 in regulating mitochondrial apoptotic signaling.\",\n      \"method\": \"Co-immunoprecipitation, immunofluorescence, protein structural simulation, cycloheximide chase (half-life assay), CCK-8 viability assay, apoptosis assay, xenograft mouse model\",\n      \"journal\": \"Life sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal Co-IP and multiple functional assays in one study; single lab\",\n      \"pmids\": [\"37805164\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"lncBADR binds directly to Mccc1 (and Pcca) in T cells and inhibits branched-chain amino acid (BCAA) degradation; this BCAA accumulation activates the mTOR-Stat1 signaling pathway, promotes IFN-γ secretion, and drives pathogenic T cell function in experimental autoimmune encephalomyelitis. Knockout of lncBADR restored BCAA degradation and reduced IFN-γ secretion.\",\n      \"method\": \"lncRNA-protein binding assay, T cell-specific knockout mouse, EAE model, metabolic profiling, mTOR-Stat1 pathway analysis, high-BCAA diet rescue experiment\",\n      \"journal\": \"Journal of neuroinflammation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — genetic KO with defined phenotype, pathway placement via epistasis, and metabolic rescue; single lab\",\n      \"pmids\": [\"41013574\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"MCCC1 is directly bound by corosolic acid (CA) and its derivatives, as identified by a CA-biotin chemical probe combined with avidin-biotin affinity pull-down and quantitative proteomics; binding to MCCC1 was linked mechanistically to modulation of the insulin resistance signaling pathway in type 2 diabetes models.\",\n      \"method\": \"Chemical probe (CA-biotin) affinity pull-down, quantitative proteomics, in vitro interaction validation, T2DM mouse model\",\n      \"journal\": \"European journal of medicinal chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — chemical proteomics identifies direct binding, supported by in vivo functional data; single lab\",\n      \"pmids\": [\"39731787\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"The intronic PD-associated variant rs12637471 in MCCC1 regulates MCCC1 mRNA expression: G-allele carriers show significantly elevated MCCC1 mRNA in postmortem brain tissue, and CRISPR/Cas9-edited isogenic iPSC-derived dopaminergic neurons differing only at rs12637471 confirmed increased MCCC1 expression in G-allele neurons, implicating MCCC1 dysregulation in mitochondrial homeostasis relevant to PD.\",\n      \"method\": \"Postmortem brain mRNA quantification, CRISPR/Cas9 isogenic iPSC line generation, iPSC differentiation to dopaminergic neurons, gene expression analysis\",\n      \"journal\": \"Journal of human genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — isogenic CRISPR lines provide clean causal evidence for variant effect on expression; single lab\",\n      \"pmids\": [\"40216992\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"MCCC1 protein is abundantly expressed in mitochondria-rich organs (heart, skeletal muscle, kidney, liver), consistent with its mitochondrial targeting signal peptide, and localizes to mitochondria.\",\n      \"method\": \"Northern blot / tissue expression analysis, bioinformatic signal peptide analysis\",\n      \"journal\": \"Genomics\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3-4 — localization inferred from expression pattern and domain prediction without direct imaging/fractionation\",\n      \"pmids\": [\"11401427\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"MCCC1 encodes the biotin-containing alpha-subunit of the mitochondrial 3-methylcrotonyl-CoA carboxylase (MCC) complex, where it catalyzes a key step in leucine catabolism; beyond this enzymatic role, MCCC1 protein interacts with the pro-apoptotic protein Bad to regulate mitochondrial apoptotic signaling, is bound by lncRNAs (AABR07005593.1 and lncBADR) that co-opt its function to modulate NF-κB/IL-6 and mTOR-Stat1/IFN-γ inflammatory pathways respectively, and directly binds corosolic acid in the context of insulin resistance, while a regulatory intronic variant (rs12637471) controls its mRNA expression level in dopaminergic neurons.\"\n}\n```\n\n--- ROUND 2 (R2/R3, augmented corpus) ---\n\n```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2001,\n      \"finding\": \"The human MCCC1 (MCCA) gene encodes the 725-amino-acid biotin-containing alpha-subunit of 3-methylcrotonyl-CoA carboxylase (MCC), a mitochondrial enzyme involved in leucine catabolism. The MCCA cDNA was cloned, the gene mapped to chromosome 3q26-q28 with 19 exons, and mutations (S535F, V694X compound heterozygosity) in MCCA were correlated with near-total loss of MCC enzyme activity in patient fibroblasts, establishing MCCA as causative for 3-methylcrotonyl-CoA carboxylase deficiency.\",\n      \"method\": \"cDNA cloning, chromosomal mapping, patient mutation sequencing, fibroblast enzyme activity assay\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — direct cloning, gene characterization, and mutation-to-enzyme activity correlation in patient-derived cells; replicated in a second independent paper (PMID:11401427)\",\n      \"pmids\": [\"11406611\", \"11401427\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"MCCC1 (MCCA) protein contains mitochondrial signal peptide, biotin carboxylase, and biotin-carrier protein domains. The gene is abundantly expressed in mitochondria-rich organs (heart, skeletal muscle, kidney, liver), consistent with its mitochondrial enzymatic role in leucine and isovalerate catabolism.\",\n      \"method\": \"cDNA sequence analysis, northern blot/expression profiling, chromosomal mapping\",\n      \"journal\": \"Genomics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — direct sequence characterization with domain identification and expression data; single lab\",\n      \"pmids\": [\"11401427\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"Four missense mutations in MCCA (two) and MCCB (two), mapped to evolutionarily conserved residues, were expressed by transient transfection in MCC-deficient fibroblasts and all resulted in null or severely diminished MCC carboxylase activity, directly confirming their pathogenicity. Structural modelling of MCCA mutations in the context of the E. coli acetyl-CoA carboxylase biotin carboxylase subunit crystal structure provided mechanistic explanation for loss of function.\",\n      \"method\": \"Transient transfection in deficient fibroblasts, enzyme activity assay, 3D structural modelling\",\n      \"journal\": \"Molecular genetics and metabolism\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — functional reconstitution in deficient cells with enzyme activity readout plus structural modelling; multiple mutations tested\",\n      \"pmids\": [\"14680978\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Crystal structures of the MCC holoenzyme (containing the MCCC1/alpha subunit) revealed an unanticipated architecture with previously unrecognized domains and provided a molecular basis for understanding the catalytic mechanism of biotin-dependent carboxylation in leucine catabolism, as well as explaining disease-causing mutations.\",\n      \"method\": \"Crystal structure determination of MCC holoenzyme\",\n      \"journal\": \"Cellular and molecular life sciences : CMLS\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — structural determination with functional interpretation; comprehensive review of MCC holoenzyme structure\",\n      \"pmids\": [\"22869039\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"MCCC1 (MCCA) physically interacts with the pro-apoptotic protein Bad in multiple myeloma cells, as demonstrated by immunoprecipitation and immunofluorescence. MCCC1 knockdown shortened the half-life of Bad (from 7.34 to 2.42 h) and shifted the apoptotic balance toward anti-apoptotic proteins (increased Bcl-xl and Mcl-1, decreased Bax and Bad), leading to multidrug resistance and mitochondrial dysfunction.\",\n      \"method\": \"Immunoprecipitation, immunofluorescence, protein structural simulation, CCK-8 viability assay, apoptosis assay, in vivo xenograft model\",\n      \"journal\": \"Life sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — Co-IP plus functional KD with defined cellular phenotype; single lab, multiple orthogonal methods\",\n      \"pmids\": [\"37805164\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"lncRNA AABR07005593.1, upregulated by PM2.5 exposure, was shown by ChIRP-MS and western blot to interact physically with MCCC1 protein, and this interaction was required for activation of the NF-κB pathway and downstream IL-6 expression in rat alveolar macrophages.\",\n      \"method\": \"ChIRP-MS, western blot, RNA interference, in vivo rat inflammation model\",\n      \"journal\": \"Ecotoxicology and environmental safety\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — ChIRP-MS identification of MCCC1 as lncRNA binding partner with functional RNAi follow-up; single lab\",\n      \"pmids\": [\"34619471\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"The lncRNA lncBADR binds directly to Mccc1 (and Pcca) in T cells, inhibiting branched-chain amino acid (BCAA) degradation. This leads to intracellular BCAA accumulation, mTOR-Stat1 pathway activation, and increased IFN-γ secretion promoting autoimmune encephalomyelitis. T cell-specific lncBADR knockout restored BCAA degradation and reduced pathogenic T cell function.\",\n      \"method\": \"T cell-specific knockout mouse model (EAE), RNA-protein binding assay, metabolic assays, mTOR-Stat1 pathway analysis, high-BCAAs feeding rescue experiment\",\n      \"journal\": \"Journal of neuroinflammation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — genetic KO with defined metabolic and immunological phenotype plus rescue experiment; single lab\",\n      \"pmids\": [\"41013574\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Corosolic acid (CA) and its derivative H26 directly bind to MCCC1, identified by avidin-biotin affinity pull-down with CA-biotin chemical probe followed by quantitative proteomics. This interaction was confirmed in vitro, and MCCC1 was identified as a target in the insulin resistance signaling pathway, with CA/H26 showing hypoglycemic effects in type 2 diabetic mice.\",\n      \"method\": \"Avidin-biotin affinity pull-down, quantitative proteomics, in vitro binding assay, T2DM mouse model\",\n      \"journal\": \"European journal of medicinal chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 — chemical probe-based target identification with in vitro confirmation and in vivo phenotype; single lab\",\n      \"pmids\": [\"39731787\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"The intronic PD-risk variant rs12637471 in MCCC1 regulates MCCC1 mRNA expression: G-allele carriers show significantly elevated MCCC1 mRNA in postmortem brain tissue (consistent with GTEx eQTL data), and CRISPR/Cas9-edited isogenic iPSC-derived dopaminergic neurons carrying the G-allele show increased MCCC1 expression, implicating MCCC1 dysregulation in mitochondrial homeostasis or inflammation relevant to Parkinson's disease.\",\n      \"method\": \"Postmortem brain RNA analysis, CRISPR/Cas9 isogenic iPSC line generation, iPSC differentiation to dopaminergic neurons, mRNA quantification\",\n      \"journal\": \"Journal of human genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — CRISPR isogenic system with neuronal differentiation and expression readout; single lab, moderate mechanistic depth\",\n      \"pmids\": [\"40216992\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"MCCC1 encodes the biotin-containing alpha-subunit of the mitochondrial heteromeric enzyme 3-methylcrotonyl-CoA carboxylase (MCC), which catalyzes a critical step in leucine catabolism; loss-of-function mutations cause MCC deficiency, the holoenzyme structure has been determined by crystallography revealing the catalytic mechanism, and MCCC1 additionally interacts with the pro-apoptotic protein Bad to regulate mitochondrial apoptotic signaling in cancer cells, is bound by lncRNAs (lncBADR, AABR07005593.1) that inhibit its BCAA-degrading activity or modulate NF-κB-driven inflammation, and is directly targeted by corosolic acid in the insulin resistance pathway.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"MCCC1 encodes the biotin-containing alpha subunit of the mitochondrial 3-methylcrotonyl-CoA carboxylase (MCC) complex, which catalyzes an essential carboxylation step in leucine catabolism. Cloning of the gene, mapping to chromosome 3q27, and functional expression studies demonstrated that patient-derived missense mutations at conserved residues abolish MCC enzyme activity, establishing MCCC1 deficiency as the cause of 3-methylcrotonyl-CoA carboxylase deficiency [PMID:11406611, PMID:14680978]. Beyond its metabolic role, MCCC1 physically interacts with the pro-apoptotic protein Bad to stabilize it and promote mitochondrial apoptotic signaling, and serves as a direct binding target for lncRNAs (AABR07005593.1 and lncBADR) that modulate NF-κB and mTOR-Stat1 inflammatory pathways by co-opting MCCC1-dependent branched-chain amino acid catabolism [PMID:37805164, PMID:34619471, PMID:41013574]. A Parkinson's disease-associated intronic variant (rs12637471) regulates MCCC1 mRNA levels in dopaminergic neurons, linking altered MCCC1 expression to mitochondrial homeostasis in neurodegeneration [PMID:40216992].\",\n  \"teleology\": [\n    {\n      \"year\": 2001,\n      \"claim\": \"Identification of MCCC1 as the biotin-containing catalytic subunit of mitochondrial MCC resolved the molecular basis of 3-methylcrotonyl-CoA carboxylase deficiency and placed the gene within leucine catabolism.\",\n      \"evidence\": \"cDNA cloning, chromosomal mapping, mutation sequencing, and fibroblast enzyme activity assays in patient-derived cells\",\n      \"pmids\": [\"11406611\", \"11401427\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Crystal structure of the human MCC holoenzyme not determined\",\n        \"Regulation of MCCC1 expression and its transcriptional control not addressed\",\n        \"Stoichiometry and assembly mechanism of the alpha-beta MCC complex not resolved\"\n      ]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Functional expression of patient missense mutations demonstrated that conserved residues in the biotin carboxylase domain are essential for catalytic activity, providing a structure–function framework for pathogenic variants.\",\n      \"evidence\": \"Transient transfection of MCCA constructs into SV40-transformed deficient fibroblasts with direct enzyme activity measurement and structural modeling based on the E. coli biotin carboxylase subunit\",\n      \"pmids\": [\"14680978\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"No human MCC crystal structure to confirm modeled residue positions\",\n        \"Contribution of individual residues to biotin binding versus substrate binding not dissected\",\n        \"Genotype–phenotype spectrum across a broader patient cohort not established\"\n      ]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Discovery that a lncRNA (AABR07005593.1) physically binds MCCC1 protein to activate NF-κB/IL-6 signaling revealed a non-enzymatic regulatory dimension of MCCC1 in innate immune inflammation.\",\n      \"evidence\": \"ChIRP-MS identification of MCCC1 as RNA-binding partner, western blot, and RNAi knockdown in PM2.5-exposed macrophages\",\n      \"pmids\": [\"34619471\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Binding domain on MCCC1 not mapped\",\n        \"Mechanism linking MCCC1–lncRNA interaction to NF-κB activation not defined\",\n        \"Single-study observation not independently replicated\"\n      ]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Demonstration that MCCC1 binds and stabilizes Bad, thereby promoting mitochondrial apoptosis, uncovered a direct pro-apoptotic signaling role distinct from its metabolic function.\",\n      \"evidence\": \"Reciprocal co-immunoprecipitation, cycloheximide chase, apoptosis assays, and xenograft model in multiple myeloma cells\",\n      \"pmids\": [\"37805164\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"MCCC1–Bad binding interface not structurally characterized\",\n        \"Whether the interaction requires MCCC1 catalytic activity or biotin cofactor is unknown\",\n        \"Findings from a single lab in one cancer type\"\n      ]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Chemical proteomics identified MCCC1 as a direct binding target of corosolic acid, connecting MCCC1 to insulin resistance signaling in type 2 diabetes models.\",\n      \"evidence\": \"CA-biotin affinity pull-down, quantitative proteomics, and in vivo validation in T2DM mouse model\",\n      \"pmids\": [\"39731787\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Binding site on MCCC1 and consequence for enzymatic activity not determined\",\n        \"Whether corosolic acid binding alters BCAA catabolism not tested\",\n        \"Single-lab chemical proteomics without orthogonal biophysical confirmation of binding affinity\"\n      ]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Two studies extended MCCC1 biology into neurodegeneration and autoimmune inflammation: an intronic PD-risk variant (rs12637471) was shown to regulate MCCC1 expression in dopaminergic neurons via CRISPR-edited isogenic iPSCs, while lncBADR binding to MCCC1 in T cells inhibited BCAA degradation, activating mTOR-Stat1/IFN-γ to drive pathogenic T cell responses in EAE.\",\n      \"evidence\": \"CRISPR/Cas9 isogenic iPSC-derived dopaminergic neurons with gene expression analysis; lncBADR-knockout mice, metabolic profiling, and high-BCAA diet rescue in EAE model\",\n      \"pmids\": [\"40216992\", \"41013574\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Mechanism by which rs12637471 alters transcription (e.g., enhancer disruption) not elucidated\",\n        \"Whether lncBADR binding directly blocks MCCC1 enzymatic activity or displaces substrate not resolved\",\n        \"Downstream metabolic consequences of MCCC1 overexpression in dopaminergic neurons not characterized\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"A high-resolution structure of the human MCC holoenzyme, the precise mechanism by which lncRNA binding and Bad interaction interface with MCCC1's catalytic versus non-catalytic surfaces, and the in vivo relevance of MCCC1 as a drug target in inflammation and neurodegeneration remain to be established.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No crystal or cryo-EM structure of human MCC complex\",\n        \"Whether MCCC1's metabolic and signaling functions are coupled or independent is unknown\",\n        \"Tissue-specific conditional knockout phenotypes have not been characterized\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016874\", \"supporting_discovery_ids\": [0, 1]},\n      {\"term_id\": \"GO:0140657\", \"supporting_discovery_ids\": [0, 1]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [0, 7]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [0, 1, 4]},\n      {\"term_id\": \"R-HSA-5357801\", \"supporting_discovery_ids\": [3]}\n    ],\n    \"complexes\": [\n      \"3-methylcrotonyl-CoA carboxylase (MCC)\"\n    ],\n    \"partners\": [\n      \"MCCC2\",\n      \"BAD\",\n      \"PCCA\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```\n\n--- ROUND 2 (R2/R3, augmented corpus) ---\n\n```json\n{\n  \"mechanistic_narrative\": \"MCCC1 encodes the biotin-containing alpha subunit of the mitochondrial 3-methylcrotonyl-CoA carboxylase (MCC) holoenzyme, which catalyzes a biotin-dependent carboxylation step essential for leucine catabolism. The protein harbors a mitochondrial targeting signal, a biotin carboxylase domain, and a biotin-carrier protein domain, and is highly expressed in mitochondria-rich tissues such as heart, skeletal muscle, kidney, and liver [PMID:11406611, PMID:11401427]. Loss-of-function mutations in MCCC1 abolish MCC enzyme activity and cause 3-methylcrotonyl-CoA carboxylase deficiency, a Mendelian organic aciduria, with the crystal structure of the holoenzyme providing a molecular framework for understanding pathogenic variants [PMID:14680978, PMID:22869039]. Beyond its metabolic role, MCCC1 physically interacts with the pro-apoptotic protein Bad to stabilize it and regulate mitochondrial apoptotic signaling, and serves as a direct binding target of regulatory lncRNAs (lncBADR, AABR07005593.1) that modulate BCAA degradation and NF-κB-driven inflammation [PMID:37805164, PMID:41013574, PMID:34619471].\",\n  \"teleology\": [\n    {\n      \"year\": 2001,\n      \"claim\": \"Cloning of MCCC1 established the molecular identity of the biotin-containing alpha subunit of MCC and linked mutations directly to loss of enzyme activity, resolving the genetic basis of MCC deficiency.\",\n      \"evidence\": \"cDNA cloning, chromosomal mapping, and enzyme activity assays in patient fibroblasts carrying compound heterozygous mutations\",\n      \"pmids\": [\"11406611\", \"11401427\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Three-dimensional structure of the holoenzyme not yet determined\",\n        \"Spectrum of pathogenic alleles and genotype-phenotype correlations incomplete\",\n        \"No reconstitution of purified recombinant holoenzyme to measure kinetics\"\n      ]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Functional expression of disease-associated missense mutations in MCC-deficient fibroblasts confirmed their pathogenicity by demonstrating null or severely reduced carboxylase activity, validating the causal link between specific MCCC1 residues and catalytic function.\",\n      \"evidence\": \"Transient transfection rescue in deficient fibroblasts with enzyme activity measurement and structural modelling against the E. coli biotin carboxylase crystal structure\",\n      \"pmids\": [\"14680978\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Structural modelling relied on a bacterial homolog rather than the human MCC structure\",\n        \"Mechanism of substrate specificity for methylcrotonyl-CoA not addressed\"\n      ]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Crystal structure determination of the MCC holoenzyme revealed an unexpected architecture with previously unrecognized domains, providing the first atomic-level explanation for the catalytic mechanism and for how disease mutations disrupt function.\",\n      \"evidence\": \"X-ray crystallography of the MCC holoenzyme complex\",\n      \"pmids\": [\"22869039\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Dynamics of biotin translocation between catalytic sites not captured by static structure\",\n        \"No co-crystal with the methylcrotonyl-CoA substrate reported\"\n      ]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Identification of lncRNA AABR07005593.1 as a physical binding partner of MCCC1 revealed an unexpected role for the enzyme in NF-κB pathway activation and inflammatory cytokine production, extending MCCC1 function beyond leucine catabolism.\",\n      \"evidence\": \"ChIRP-MS target identification with RNAi validation in rat alveolar macrophages and an in vivo PM2.5 inflammation model\",\n      \"pmids\": [\"34619471\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Mechanism by which MCCC1–lncRNA interaction activates NF-κB is undefined\",\n        \"Single lab finding in a rat system without human cell validation\",\n        \"Unclear whether the catalytic activity of MCCC1 is required for this non-metabolic role\"\n      ]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Discovery that MCCC1 physically interacts with and stabilizes Bad in multiple myeloma cells established a non-canonical role for MCCC1 in mitochondrial apoptotic signaling and drug resistance.\",\n      \"evidence\": \"Co-immunoprecipitation, immunofluorescence, protein half-life assays, and xenograft models in multiple myeloma cells\",\n      \"pmids\": [\"37805164\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Binding domain on MCCC1 responsible for Bad interaction not mapped\",\n        \"Whether this interaction occurs in non-cancer cells is untested\",\n        \"No reciprocal rescue experiment to confirm specificity\"\n      ]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Chemical probe-based target identification showed corosolic acid directly binds MCCC1, implicating the enzyme in insulin resistance signaling and suggesting it as a druggable target for glucose homeostasis.\",\n      \"evidence\": \"Avidin-biotin affinity pull-down with quantitative proteomics and in vitro binding confirmation; hypoglycemic effects in T2DM mice\",\n      \"pmids\": [\"39731787\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Binding site of corosolic acid on MCCC1 not determined\",\n        \"Whether binding modulates carboxylase activity or a non-enzymatic function is unknown\",\n        \"Single lab; no genetic validation (e.g., MCCC1 KO rescue) provided\"\n      ]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"lncBADR was shown to bind MCCC1 in T cells and inhibit BCAA degradation, causing intracellular BCAA accumulation that drives mTOR-Stat1-IFN-γ signaling and autoimmune pathology, connecting MCCC1's metabolic activity to adaptive immune regulation.\",\n      \"evidence\": \"T cell-specific lncBADR knockout mice with EAE model, RNA-protein binding assays, metabolic flux measurements, and dietary BCAA rescue\",\n      \"pmids\": [\"41013574\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Binding interface between lncBADR and MCCC1 not characterized\",\n        \"Whether the effect is specific to MCCC1 or also mediated through concurrent Pcca binding is not resolved\"\n      ]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"A PD-risk intronic variant (rs12637471) was shown to regulate MCCC1 expression in dopaminergic neurons using CRISPR-edited isogenic iPSCs, linking MCCC1 dysregulation to Parkinson's disease susceptibility.\",\n      \"evidence\": \"Postmortem brain mRNA analysis and CRISPR/Cas9 isogenic iPSC-derived dopaminergic neuron differentiation with expression quantification\",\n      \"pmids\": [\"40216992\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Downstream functional consequences of elevated MCCC1 in neurons not characterized\",\n        \"No direct link to neurodegeneration phenotype beyond expression change\",\n        \"Single lab; needs replication and phenotypic readout (e.g., mitochondrial function, survival)\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How MCCC1's non-enzymatic interactions (with Bad, lncRNAs, and small molecules) relate to its canonical carboxylase activity, and whether catalytic and signaling roles are independent or coupled, remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No mutagenesis studies separating catalytic from protein-interaction functions\",\n        \"Structural basis of MCCC1 interaction with Bad and lncRNAs unknown\",\n        \"Tissue-specific non-metabolic roles not systematically assessed\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016874\", \"supporting_discovery_ids\": [0, 2, 3]},\n      {\"term_id\": \"GO:0140657\", \"supporting_discovery_ids\": [0, 3]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [0, 1, 4]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [0, 1, 2, 3, 6]}\n    ],\n    \"complexes\": [\n      \"3-methylcrotonyl-CoA carboxylase (MCC holoenzyme)\"\n    ],\n    \"partners\": [\n      \"MCCC2\",\n      \"BAD\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}