{"gene":"MAIP1","run_date":"2026-04-28T18:30:27","timeline":{"discoveries":[{"year":2016,"finding":"MAIP1 (C2ORF47) was identified as a binding partner of the mitochondrial m-AAA protease (AFG3L2/paraplegin) in neuronal mitochondria. MAIP1 assists the biogenesis of EMRE, a subunit of the mitochondrial calcium uniporter MCU. The m-AAA protease degrades non-assembled EMRE, ensuring efficient incorporation of gatekeeper subunits (MICU1/MICU2) into the MCU channel. Loss of the m-AAA protease leads to accumulation of constitutively active MCU-EMRE channels lacking gatekeeper subunits, facilitating mitochondrial Ca2+ overload, mitochondrial permeability transition pore opening, and neuronal death.","method":"Neuronal interactome mapping (affinity purification-MS), co-immunoprecipitation, siRNA knockdown/rescue, mitochondrial Ca2+ measurements, cell death assays","journal":"Molecular cell","confidence":"High","confidence_rationale":"Tier 2 — reciprocal Co-IP and interactome mapping combined with functional KD phenotype (Ca2+ overload, cell death) and pathway epistasis; multiple orthogonal methods in single rigorous study","pmids":["27642048"],"is_preprint":false},{"year":2023,"finding":"MAIP1 is a direct target of miR-27b in hepatic cells. Knockdown of MAIP1 induces lipid accumulation in human and mouse hepatic cells, while overexpression of MAIP1 ameliorates miR-27b-induced lipid accumulation. Hepatic Maip1 expression declines in mice fed a high-fat diet, implicating reduced MAIP1 expression in fatty liver development.","method":"miR-27b transfection, siRNA knockdown of MAIP1, MAIP1 overexpression rescue experiments, lipid accumulation assays (Oil Red O), luciferase 3′-UTR reporter assay confirming direct miR-27b targeting, high-fat diet mouse model","journal":"Communications biology","confidence":"Medium","confidence_rationale":"Tier 2/3 — direct target validation by reporter assay plus KD/OE phenotypic rescue in cell culture; single lab, but multiple orthogonal methods","pmids":["37355744"],"is_preprint":false}],"current_model":"MAIP1 (C2ORF47) is a mitochondrial inner-membrane-associated protein that chaperones biogenesis of the MCU subunit EMRE in cooperation with the m-AAA protease, thereby regulating assembly of gated mitochondrial Ca2+ uniporter complexes and protecting against Ca2+-induced neuronal death; additionally, MAIP1 is a direct miR-27b target whose reduction promotes hepatic lipid accumulation."},"narrative":{"teleology":[{"year":2016,"claim":"Identification of MAIP1 as an m-AAA protease interactor established its role in EMRE quality control, resolving how the MCU complex acquires gatekeeper subunits and why m-AAA protease loss causes neuronal Ca²⁺ overload and death.","evidence":"Affinity purification-MS interactome, reciprocal co-IP, siRNA knockdown/rescue, mitochondrial Ca²⁺ imaging, and cell death assays in neuronal cells","pmids":["27642048"],"confidence":"High","gaps":["Structural basis of MAIP1–m-AAA protease interaction is unresolved","Whether MAIP1 directly contacts EMRE during biogenesis or acts solely through the protease is unclear","Contribution of MAIP1 to MCU assembly in non-neuronal tissues has not been systematically tested"]},{"year":2023,"claim":"Demonstration that miR-27b directly targets MAIP1 mRNA and that MAIP1 loss promotes hepatic lipid accumulation linked MAIP1 to lipid metabolism beyond its known mitochondrial Ca²⁺ uniporter role.","evidence":"Luciferase 3′-UTR reporter assay, siRNA knockdown, MAIP1 overexpression rescue, Oil Red O staining in hepatic cell lines, and high-fat diet mouse model","pmids":["37355744"],"confidence":"Medium","gaps":["Mechanism connecting MAIP1 depletion to lipid accumulation (metabolic rewiring vs. Ca²⁺-dependent signaling) is undefined","Hepatic phenotype has not been confirmed by liver-specific Maip1 knockout in vivo","Whether the lipid phenotype depends on EMRE/MCU function remains untested"]},{"year":null,"claim":"A unifying model explaining how MAIP1's mitochondrial chaperone function integrates with its hepatic metabolic role is lacking, as is structural insight into MAIP1–protease–EMRE interactions.","evidence":"","pmids":[],"confidence":"Low","gaps":["No structural or cryo-EM model of MAIP1 in complex with m-AAA protease or EMRE","In vivo conditional knockout phenotypes in brain and liver are unavailable","Potential roles in other m-AAA protease substrate pathways have not been explored"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0044183","term_label":"protein folding chaperone","supporting_discovery_ids":[0]}],"localization":[{"term_id":"GO:0005739","term_label":"mitochondrion","supporting_discovery_ids":[0]}],"pathway":[{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[1]}],"complexes":[],"partners":["AFG3L2","SPG7","EMRE"],"other_free_text":[]},"mechanistic_narrative":"MAIP1 (C2orf47) is a mitochondrial inner-membrane-associated protein that cooperates with the m-AAA protease (AFG3L2/paraplegin) to chaperone biogenesis of EMRE, a subunit of the mitochondrial calcium uniporter (MCU), thereby ensuring incorporation of gatekeeper subunits MICU1/MICU2 into the channel and preventing constitutive mitochondrial Ca²⁺ influx that triggers permeability transition and neuronal death [PMID:27642048]. MAIP1 is also a direct miR-27b target in hepatic cells, where its depletion promotes lipid accumulation and its overexpression rescues miR-27b-induced steatotic phenotypes [PMID:37355744]."},"prefetch_data":{"uniprot":{"accession":"Q8WWC4","full_name":"m-AAA protease-interacting protein 1, mitochondrial","aliases":["Matrix AAA peptidase-interacting protein 1"],"length_aa":291,"mass_kda":32.5,"function":"Promotes sorting of SMDT1/EMRE in mitochondria by ensuring its maturation (PubMed:27642048). Interacts with the transit peptide region of SMDT1/EMRE precursor protein in the mitochondrial matrix, leading to protect it against protein degradation by YME1L1, thereby ensuring SMDT1/EMRE maturation by the mitochondrial processing peptidase (PMPCA and PMPCB) (PubMed:27642048)","subcellular_location":"Mitochondrion matrix","url":"https://www.uniprot.org/uniprotkb/Q8WWC4/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/MAIP1","classification":"Not Classified","n_dependent_lines":12,"n_total_lines":1208,"dependency_fraction":0.009933774834437087},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/MAIP1","total_profiled":1310},"omim":[{"mim_id":"617267","title":"MATRIX AAA PEPTIDASE-INTERACTING PROTEIN 1; MAIP1","url":"https://www.omim.org/entry/617267"},{"mim_id":"615588","title":"SINGLE-PASS MEMBRANE PROTEIN WITH ASPARTATE-RICH TAIL 1; SMDT1","url":"https://www.omim.org/entry/615588"},{"mim_id":"614197","title":"MITOCHONDRIAL CALCIUM UNIPORTER; MCU","url":"https://www.omim.org/entry/614197"},{"mim_id":"604581","title":"AFG3-LIKE MATRIX AAA PEPTIDASE, SUBUNIT 2; AFG3L2","url":"https://www.omim.org/entry/604581"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Mitochondria","reliability":"Supported"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/MAIP1"},"hgnc":{"alias_symbol":["DKFZp666A212","FLJ22555"],"prev_symbol":["C2orf47"]},"alphafold":{"accession":"Q8WWC4","domains":[{"cath_id":"3.10.450","chopping":"117-228_263-285","consensus_level":"high","plddt":93.481,"start":117,"end":285}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8WWC4","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q8WWC4-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q8WWC4-F1-predicted_aligned_error_v6.png","plddt_mean":67.0},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=MAIP1","jax_strain_url":"https://www.jax.org/strain/search?query=MAIP1"},"sequence":{"accession":"Q8WWC4","fasta_url":"https://rest.uniprot.org/uniprotkb/Q8WWC4.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q8WWC4/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8WWC4"}},"corpus_meta":[{"pmid":"27499296","id":"PMC_27499296","title":"Mitochondrial Protein Interaction Mapping Identifies Regulators of Respiratory Chain Function.","date":"2016","source":"Molecular cell","url":"https://pubmed.ncbi.nlm.nih.gov/27499296","citation_count":220,"is_preprint":false,"source_track":"pubmed_title"},{"pmid":"27642048","id":"PMC_27642048","title":"The m-AAA Protease Associated with Neurodegeneration Limits MCU Activity in Mitochondria.","date":"2016","source":"Molecular cell","url":"https://pubmed.ncbi.nlm.nih.gov/27642048","citation_count":164,"is_preprint":false,"source_track":"pubmed_title"},{"pmid":"24703095","id":"PMC_24703095","title":"Immunosuppressive PAS-1 is an excretory/secretory protein released by larval and adult worms of the ascarid nematode Ascaris suum.","date":"2014","source":"Journal of helminthology","url":"https://pubmed.ncbi.nlm.nih.gov/24703095","citation_count":17,"is_preprint":false,"source_track":"pubmed_title"},{"pmid":"16519731","id":"PMC_16519731","title":"PAS-1, a protein affinity purified from Ascaris suum worms, maintains the ability to modulate the immune response to a bystander antigen.","date":"2006","source":"Immunology and cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/16519731","citation_count":13,"is_preprint":false,"source_track":"pubmed_title"},{"pmid":"18691141","id":"PMC_18691141","title":"Helminth products as a potential therapeutic strategy for inflammatory diseases.","date":"2008","source":"Inflammation & allergy drug targets","url":"https://pubmed.ncbi.nlm.nih.gov/18691141","citation_count":12,"is_preprint":false,"source_track":"pubmed_title"},{"pmid":"37355744","id":"PMC_37355744","title":"miR-27b targets MAIP1 to mediate lipid accumulation in cultured human and mouse hepatic cells.","date":"2023","source":"Communications biology","url":"https://pubmed.ncbi.nlm.nih.gov/37355744","citation_count":9,"is_preprint":false,"source_track":"pubmed_title"},{"pmid":"36530928","id":"PMC_36530928","title":"Identification of Sex-Specific Genetic Variants Associated With Tau PET.","date":"2022","source":"Neurology. 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disease","url":"https://pubmed.ncbi.nlm.nih.gov/34650049","citation_count":64,"is_preprint":false,"source_track":"gene2pubmed"}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":6178,"output_tokens":1060,"usd":0.017217},"stage2":{"model":"claude-opus-4-6","input_tokens":4263,"output_tokens":1233,"usd":0.07821},"total_usd":0.247513,"stage1_batch_id":"msgbatch_01Mgbec4vM6c9vXht7JVJzss","stage2_batch_id":"msgbatch_01JkuuH5RB2BdJNsgnhjbC6s","note":"batch pricing = 50% of standard","round2_stage1":{"model":"claude-sonnet-4-6","input_tokens":19101,"output_tokens":1386,"usd":0.039046},"round2_rules_fired":"R3","round2_stage2":{"model":"claude-opus-4-6","input_tokens":4182,"output_tokens":2178,"usd":0.11304}},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2016,\n      \"finding\": \"MAIP1 (C2ORF47) forms a complex with m-AAA proteases in the mitochondrial inner membrane and assists biogenesis of the MCU subunit EMRE, thereby regulating assembly of the mitochondrial Ca2+ uniporter (MCU). The m-AAA protease degrades non-assembled EMRE and ensures efficient incorporation of gatekeeper subunits with MCU. Loss of m-AAA protease leads to accumulation of constitutively active MCU-EMRE channels lacking gatekeeper subunits, facilitating mitochondrial Ca2+ overload, permeability transition pore opening, and neuronal death.\",\n      \"method\": \"Neuronal interactome mapping (Co-immunoprecipitation/affinity enrichment mass spectrometry), genetic loss-of-function in mice, functional Ca2+ uptake assays, assessment of MCU complex assembly\",\n      \"journal\": \"Molecular cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal Co-IP/interactome + clean KO with defined cellular phenotype (neuronal death via Ca2+ overload) + mechanistic pathway placement\",\n      \"pmids\": [\"27642048\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"MAIP1 (C2ORF47) was identified as an MXP (mitochondrial protein of unknown function) through condition-specific protein-protein interaction mapping, connecting it to mitochondrial processes.\",\n      \"method\": \"Affinity enrichment mass spectrometry (protein-protein interaction mapping of 50 mitochondrial proteins)\",\n      \"journal\": \"Molecular cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — large-scale MS interactome study; MAIP1 interaction data reported but not individually validated in depth in this paper\",\n      \"pmids\": [\"27499296\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"MAIP1 is a direct target of miR-27b in hepatic cells; knockdown of MAIP1 induces lipid accumulation, and overexpression of MAIP1 ameliorates miR-27b-induced lipid accumulation, identifying a MAIP1/miR-27b axis as a mediator of hepatic lipid metabolism.\",\n      \"method\": \"miR-27b transfection in human and mouse hepatic cell lines, siRNA knockdown of MAIP1, MAIP1 overexpression rescue, luciferase reporter assay (direct target validation), lipid staining assays\",\n      \"journal\": \"Communications biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2/3 — direct target validated by reporter assay + KD/OE with defined lipid accumulation phenotype; single lab study\",\n      \"pmids\": [\"37355744\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Gene-gene interaction analysis revealed that PFKFB3 rs1983890 interacts epistatically with MAIP1, implicating MAIP1 as an anti-apoptotic gene whose positive epistasis with PFKFB3 prolongs survival of dysfunctional 'loser' β-cells in type 2 diabetes.\",\n      \"method\": \"scRNA-seq and spatial transcriptomics gene-gene interaction analysis; PFKFB3 inhibition in mouse T2D model\",\n      \"journal\": \"Life science alliance\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 4 — computational/transcriptomic epistasis inference without direct biochemical validation of MAIP1 mechanism\",\n      \"pmids\": [\"39313296\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"MAIP1 (C2ORF47) is a mitochondrial inner membrane protein that assists EMRE biogenesis and MCU complex assembly in cooperation with m-AAA proteases to regulate mitochondrial Ca2+ homeostasis, and also participates in hepatic lipid metabolism as a direct target of miR-27b.\"\n}\n```\n\n--- ROUND 2 (R2/R3, augmented corpus) ---\n\nI'll classify each paper first, then extract discoveries only from KEEP papers.\n\n**Classification:**\n\n- [Retrieved 1] PMID:27499296 — Mitochondrial protein interactions, identifies MXPs including C17orf89 and LYRM5; mentions CoQ biosynthesis. No direct MAIP1 mechanistic content. EXCLUDE (not about MAIP1).\n- [Retrieved 2] PMID:27642048 — Directly identifies C2ORF47 as MAIP1, describes its role in MCU assembly and m-AAA protease interaction. **KEEP**\n- [Retrieved 3] PMID:24703095 — About PAS-1 protein from *Ascaris suum*; MAIP-1 is a monoclonal antibody name, not the gene MAIP1. EXCLUDE (alias collision).\n- [Retrieved 4] PMID:16519731 — Same as above; MAIP-1 is an antibody against PAS-1. EXCLUDE.\n- [Retrieved 5] PMID:18691141 — Same Ascaris/PAS-1 context. EXCLUDE.\n- [Retrieved 6] PMID:37355744 — Directly about MAIP1 (matrix AAA peptidase interacting protein 1) and miR-27b in hepatic lipid accumulation. **KEEP**\n- [Retrieved 7] PMID:36530928 — GWAS/tau PET study; C2orf47 mentioned only as a genomic locus in genetic association analysis. No mechanistic content about MAIP1 protein. EXCLUDE.\n- [Retrieved 8] PMID:35629146 — GWAS hypertension; C2orf47-SPATS2L locus mentioned as association. No mechanistic content. EXCLUDE.\n- [Retrieved 9] PMID:38339307 — MAIP1 mentioned as upregulated in biomarker analysis; expression correlation only. EXCLUDE.\n- [Retrieved 10] PMID:39313296 — Gene-gene interaction analysis implicating MAIP1 as anti-apoptotic in β-cells; computational/epistasis inference without direct mechanistic experiment on MAIP1. EXCLUDE (Tier 4 only).\n\n**gene2pubmed papers:** All 30 are large-scale resource/interactome/GWAS papers that mention MAIP1 only incidentally (e.g., in interaction lists, ORF collections, proteome maps) or are about completely unrelated proteins. None describe direct mechanistic experiments on MAIP1. EXCLUDE all.\n\n```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2016,\n      \"finding\": \"MAIP1 (C2ORF47) was identified as a binding partner of the mitochondrial m-AAA protease (AFG3L2/paraplegin) in neuronal mitochondria. MAIP1 assists the biogenesis of EMRE, a subunit of the mitochondrial calcium uniporter MCU. The m-AAA protease degrades non-assembled EMRE, ensuring efficient incorporation of gatekeeper subunits (MICU1/MICU2) into the MCU channel. Loss of the m-AAA protease leads to accumulation of constitutively active MCU-EMRE channels lacking gatekeeper subunits, facilitating mitochondrial Ca2+ overload, mitochondrial permeability transition pore opening, and neuronal death.\",\n      \"method\": \"Neuronal interactome mapping (affinity purification-MS), co-immunoprecipitation, siRNA knockdown/rescue, mitochondrial Ca2+ measurements, cell death assays\",\n      \"journal\": \"Molecular cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal Co-IP and interactome mapping combined with functional KD phenotype (Ca2+ overload, cell death) and pathway epistasis; multiple orthogonal methods in single rigorous study\",\n      \"pmids\": [\"27642048\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"MAIP1 is a direct target of miR-27b in hepatic cells. Knockdown of MAIP1 induces lipid accumulation in human and mouse hepatic cells, while overexpression of MAIP1 ameliorates miR-27b-induced lipid accumulation. Hepatic Maip1 expression declines in mice fed a high-fat diet, implicating reduced MAIP1 expression in fatty liver development.\",\n      \"method\": \"miR-27b transfection, siRNA knockdown of MAIP1, MAIP1 overexpression rescue experiments, lipid accumulation assays (Oil Red O), luciferase 3′-UTR reporter assay confirming direct miR-27b targeting, high-fat diet mouse model\",\n      \"journal\": \"Communications biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2/3 — direct target validation by reporter assay plus KD/OE phenotypic rescue in cell culture; single lab, but multiple orthogonal methods\",\n      \"pmids\": [\"37355744\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"MAIP1 (C2ORF47) is a mitochondrial inner-membrane-associated protein that chaperones biogenesis of the MCU subunit EMRE in cooperation with the m-AAA protease, thereby regulating assembly of gated mitochondrial Ca2+ uniporter complexes and protecting against Ca2+-induced neuronal death; additionally, MAIP1 is a direct miR-27b target whose reduction promotes hepatic lipid accumulation.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"MAIP1 (C2ORF47) is a mitochondrial inner membrane protein that forms a complex with m-AAA proteases to assist biogenesis of EMRE, a subunit of the mitochondrial calcium uniporter (MCU), thereby ensuring proper MCU complex assembly and preventing constitutively active MCU-EMRE channels that cause mitochondrial Ca²⁺ overload and neuronal death [PMID:27642048]. MAIP1 also functions in hepatic lipid metabolism, where it is a direct target of miR-27b; MAIP1 knockdown induces lipid accumulation in hepatic cells, and its overexpression rescues miR-27b-driven lipid accumulation [PMID:37355744].\",\n  \"teleology\": [\n    {\n      \"year\": 2016,\n      \"claim\": \"The discovery that MAIP1 complexes with m-AAA proteases and facilitates EMRE biogenesis established it as a key assembly factor for the mitochondrial Ca²⁺ uniporter, resolving how gatekeeper subunit incorporation is quality-controlled to prevent Ca²⁺ overload and neuronal death.\",\n      \"evidence\": \"Co-IP/affinity enrichment mass spectrometry interactome, mouse genetic loss-of-function, Ca²⁺ uptake assays, and MCU complex assembly analysis in neurons\",\n      \"pmids\": [\"27642048\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Direct structural basis of MAIP1–m-AAA protease interaction is unknown\",\n        \"Whether MAIP1 has catalytic activity or acts solely as an adaptor/scaffold is unresolved\",\n        \"Role of MAIP1 in MCU assembly in non-neuronal tissues not characterized in this study\"\n      ]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Large-scale mitochondrial interactome mapping independently identified MAIP1 as a mitochondrial protein connected to inner membrane processes, corroborating its mitochondrial localization and interaction network.\",\n      \"evidence\": \"Affinity enrichment mass spectrometry of 50 mitochondrial proteins\",\n      \"pmids\": [\"27499296\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Specific interaction partners from this screen were not individually validated in depth\",\n        \"No functional phenotype attributed to MAIP1 in this study alone\"\n      ]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Identification of MAIP1 as a direct miR-27b target in hepatocytes expanded its functional scope beyond MCU assembly to lipid metabolism, showing that MAIP1 loss drives lipid accumulation.\",\n      \"evidence\": \"miR-27b transfection, siRNA knockdown, overexpression rescue, luciferase reporter assay, and lipid staining in human and mouse hepatic cell lines\",\n      \"pmids\": [\"37355744\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Mechanism linking MAIP1 loss to lipid accumulation (e.g., via mitochondrial Ca²⁺ dysregulation or an independent pathway) is not delineated\",\n        \"In vivo validation in animal models of hepatic steatosis not performed\",\n        \"Single-lab finding without independent replication\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"It remains unknown whether MAIP1's roles in MCU assembly and hepatic lipid metabolism are mechanistically connected (e.g., via mitochondrial Ca²⁺ homeostasis), and no structural or enzymatic characterization of MAIP1 has been reported.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No structural model of MAIP1 or the MAIP1–m-AAA protease complex exists\",\n        \"Whether MAIP1 possesses intrinsic enzymatic or adaptor activity is unresolved\",\n        \"The relationship between MAIP1-dependent MCU assembly and its lipid metabolism role is unexplored\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [0, 1]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0382551\", \"supporting_discovery_ids\": []},\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [2]}\n    ],\n    \"complexes\": [\n      \"m-AAA protease complex\",\n      \"MCU complex (assembly intermediate)\"\n    ],\n    \"partners\": [\n      \"AFG3L2\",\n      \"SPG7\",\n      \"EMRE\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```\n\n--- ROUND 2 (R2/R3, augmented corpus) ---\n\n```json\n{\n  \"mechanistic_narrative\": \"MAIP1 (C2orf47) is a mitochondrial inner-membrane-associated protein that cooperates with the m-AAA protease (AFG3L2/paraplegin) to chaperone biogenesis of EMRE, a subunit of the mitochondrial calcium uniporter (MCU), thereby ensuring incorporation of gatekeeper subunits MICU1/MICU2 into the channel and preventing constitutive mitochondrial Ca²⁺ influx that triggers permeability transition and neuronal death [PMID:27642048]. MAIP1 is also a direct miR-27b target in hepatic cells, where its depletion promotes lipid accumulation and its overexpression rescues miR-27b-induced steatotic phenotypes [PMID:37355744].\",\n  \"teleology\": [\n    {\n      \"year\": 2016,\n      \"claim\": \"Identification of MAIP1 as an m-AAA protease interactor established its role in EMRE quality control, resolving how the MCU complex acquires gatekeeper subunits and why m-AAA protease loss causes neuronal Ca²⁺ overload and death.\",\n      \"evidence\": \"Affinity purification-MS interactome, reciprocal co-IP, siRNA knockdown/rescue, mitochondrial Ca²⁺ imaging, and cell death assays in neuronal cells\",\n      \"pmids\": [\"27642048\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Structural basis of MAIP1–m-AAA protease interaction is unresolved\",\n        \"Whether MAIP1 directly contacts EMRE during biogenesis or acts solely through the protease is unclear\",\n        \"Contribution of MAIP1 to MCU assembly in non-neuronal tissues has not been systematically tested\"\n      ]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Demonstration that miR-27b directly targets MAIP1 mRNA and that MAIP1 loss promotes hepatic lipid accumulation linked MAIP1 to lipid metabolism beyond its known mitochondrial Ca²⁺ uniporter role.\",\n      \"evidence\": \"Luciferase 3′-UTR reporter assay, siRNA knockdown, MAIP1 overexpression rescue, Oil Red O staining in hepatic cell lines, and high-fat diet mouse model\",\n      \"pmids\": [\"37355744\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Mechanism connecting MAIP1 depletion to lipid accumulation (metabolic rewiring vs. Ca²⁺-dependent signaling) is undefined\",\n        \"Hepatic phenotype has not been confirmed by liver-specific Maip1 knockout in vivo\",\n        \"Whether the lipid phenotype depends on EMRE/MCU function remains untested\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"A unifying model explaining how MAIP1's mitochondrial chaperone function integrates with its hepatic metabolic role is lacking, as is structural insight into MAIP1–protease–EMRE interactions.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No structural or cryo-EM model of MAIP1 in complex with m-AAA protease or EMRE\",\n        \"In vivo conditional knockout phenotypes in brain and liver are unavailable\",\n        \"Potential roles in other m-AAA protease substrate pathways have not been explored\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0044183\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0382551\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [1]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"AFG3L2\", \"SPG7\", \"EMRE\"],\n    \"other_free_text\": []\n  }\n}\n```\n\nWait — let me fix the pathway entry. `GO:0382551` is not a valid Reactome pathway term_id; `R-HSA-382551` is the correct one for Transport of small molecules.\n\n```json\n{\n  \"mechanistic_narrative\": \"MAIP1 (C2orf47) is a mitochondrial inner-membrane-associated protein that cooperates with the m-AAA protease (AFG3L2/paraplegin) to chaperone biogenesis of EMRE, a subunit of the mitochondrial calcium uniporter (MCU), thereby ensuring incorporation of gatekeeper subunits MICU1/MICU2 into the channel and preventing constitutive mitochondrial Ca²⁺ influx that triggers permeability transition and neuronal death [PMID:27642048]. MAIP1 is also a direct miR-27b target in hepatic cells, where its depletion promotes lipid accumulation and its overexpression rescues miR-27b-induced steatotic phenotypes [PMID:37355744].\",\n  \"teleology\": [\n    {\n      \"year\": 2016,\n      \"claim\": \"Identification of MAIP1 as an m-AAA protease interactor established its role in EMRE quality control, resolving how the MCU complex acquires gatekeeper subunits and why m-AAA protease loss causes neuronal Ca²⁺ overload and death.\",\n      \"evidence\": \"Affinity purification-MS interactome, reciprocal co-IP, siRNA knockdown/rescue, mitochondrial Ca²⁺ imaging, and cell death assays in neuronal cells\",\n      \"pmids\": [\"27642048\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Structural basis of MAIP1–m-AAA protease interaction is unresolved\",\n        \"Whether MAIP1 directly contacts EMRE during biogenesis or acts solely through the protease is unclear\",\n        \"Contribution of MAIP1 to MCU assembly in non-neuronal tissues has not been systematically tested\"\n      ]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Demonstration that miR-27b directly targets MAIP1 mRNA and that MAIP1 loss promotes hepatic lipid accumulation linked MAIP1 to lipid metabolism beyond its known mitochondrial Ca²⁺ uniporter role.\",\n      \"evidence\": \"Luciferase 3′-UTR reporter assay, siRNA knockdown, MAIP1 overexpression rescue, Oil Red O staining in hepatic cell lines, and high-fat diet mouse model\",\n      \"pmids\": [\"37355744\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Mechanism connecting MAIP1 depletion to lipid accumulation (metabolic rewiring vs. Ca²⁺-dependent signaling) is undefined\",\n        \"Hepatic phenotype has not been confirmed by liver-specific Maip1 knockout in vivo\",\n        \"Whether the lipid phenotype depends on EMRE/MCU function remains untested\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"A unifying model explaining how MAIP1's mitochondrial chaperone function integrates with its hepatic metabolic role is lacking, as is structural insight into MAIP1–protease–EMRE interactions.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No structural or cryo-EM model of MAIP1 in complex with m-AAA protease or EMRE\",\n        \"In vivo conditional knockout phenotypes in brain and liver are unavailable\",\n        \"Potential roles in other m-AAA protease substrate pathways have not been explored\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0044183\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-382551\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [1]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"AFG3L2\", \"SPG7\", \"EMRE\"],\n    \"other_free_text\": []\n  }\n}\n```"}