{"gene":"MT-ATP8","run_date":"2026-06-10T02:59:51","timeline":{"discoveries":[{"year":1983,"finding":"The unidentified reading frame A6L (URFA6L), overlapping the ATPase 6 gene, is expressed as a protein (protein #25) in human mitochondria. Antibodies against synthetic peptides corresponding to both the NH2-terminal and COOH-terminal sequences of the predicted A6L polypeptide immunoprecipitated a specific mitochondrial translation product from HeLa cells, and trypsin fingerprinting was consistent with the identification.","method":"Immunoprecipitation with anti-synthetic-peptide antibodies; tryptic fingerprinting of mitochondrial translation products","journal":"Cell","confidence":"High","confidence_rationale":"Tier 1 / Strong — direct protein identification by two independent antibodies (N- and C-terminal peptides) plus peptide fingerprinting in a landmark study","pmids":["6301689"],"is_preprint":false},{"year":1987,"finding":"Chargerin II (the URFA6L / ATP8 product) is required for energy transduction in rat liver mitochondria: antibody against chargerin II inhibited ATP–Pi exchange and reversed electron flow from succinate to NAD in mitoplasts, with greater inhibition in the energized state, indicating a conformational change coupled to redox reactions.","method":"Immunoinhibition assays in energized and non-energized mitoplasts; ATP–Pi exchange and reversed electron flow measurements","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional antibody inhibition experiments with multiple assay readouts, single lab","pmids":["3113438"],"is_preprint":false},{"year":1988,"finding":"Chargerin II purified from rat liver mitochondria was identified as the product of URFA6L (ATP8). Peptide sequencing of HPLC-purified chargerin II yielded 12 amino acids highly homologous to the predicted C-terminal sequence of the URFA6L polypeptide, and amino acid composition matched the predicted protein.","method":"HPLC purification from mitochondria; lysylendopeptidase digestion; peptide sequencing; amino acid composition analysis; Western blotting","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — direct purification and peptide sequencing establishing the identity of the protein product, replicated conceptually with earlier antibody work","pmids":["3360805"],"is_preprint":false},{"year":1989,"finding":"The orientation of chargerin II (ATP8/A6L) within the Fo sector of rat liver mitochondrial ATP synthase was determined: its N-terminal ~8 residues are exposed on the cytoplasmic (C-side) surface of Fo, while the C-terminal and charge-cluster regions are buried within Fo.","method":"Antibodies against N-terminal and C-terminal peptides applied to submitochondrial particles and intact mitochondria; immunoreactivity probed before and after membrane disruption","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — topology probed with region-specific antibodies in defined membrane orientation, single lab","pmids":["2531582"],"is_preprint":false},{"year":1990,"finding":"Chargerin II (ATP8) is present in the H+-ATP synthase of rat liver mitochondria in a 1:1 molar stoichiometry relative to the holoenzyme, as determined by radioimmunoassay of purified ATP synthase and submitochondrial particles.","method":"Radioimmunoassay of purified ATP synthase and submitochondrial particles","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — quantitative stoichiometry from a single lab using a single immunochemical method","pmids":["2139330"],"is_preprint":false},{"year":2004,"finding":"Bioinformatic sequence analysis of A6L (ATP8) across vertebrates identified a conserved aromatic residue adjacent to the N-terminal MPQL motif (MPQLX4Ar motif), proposed as functionally important for the role of A6L in the Fo membrane domain of ATP synthase.","method":"Comparative sequence alignment and homology searching","journal":"Journal of bioenergetics and biomembranes","confidence":"Low","confidence_rationale":"Tier 4 / Weak — computational/bioinformatic prediction only, no experimental validation reported","pmids":["15692730"],"is_preprint":false},{"year":2007,"finding":"A homoplasmic nonsense mutation m.8529G>A (p.Trp55X) in the mitochondrial ATP8 gene causes loss of ATP8 protein, failure to assemble Complex V holoenzyme, reduced Complex V activity, and accumulation of ATP synthase subcomplexes with residual free F1-ATPase activity. Demonstrated in patient fibroblasts, muscle, and transmitochondrial cybrid clones.","method":"Transmitochondrial cybrid generation; Blue Native PAGE with immunoblotting; in-gel ATP hydrolysis activity assay; enzyme activity measurements in fibroblasts and muscle","journal":"Journal of medical genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (cybrid validation, BN-PAGE, activity assay) in patient-derived and cybrid cells; independently replicated in case report PMID 21686774","pmids":["17954552","21686774"],"is_preprint":false},{"year":2012,"finding":"A point mutation in the murine Atp8 gene (m.7778G>T in B6-mtFVB mice) causes fragmented mitochondrial morphology, increased mitochondrial ROS generation, reduced cellular ATP levels, impaired glucose-induced insulin secretion in pancreatic islets, and higher susceptibility to palmitate stress, establishing ATP8 as required for normal β-cell mitochondrial function and secretory responsiveness.","method":"Conplastic mouse strain comparison; mitochondrial ROS measurement; ATP level assay; glucose-stimulated insulin secretion assay; morphological analysis of isolated islets","journal":"Endocrinology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic model with multiple cellular readouts, single lab","pmids":["22919063"],"is_preprint":false},{"year":2016,"finding":"Nuclear (allotopic) expression of ATP8 alone (with a mitochondrial targeting sequence) in ATP8-null cybrid cells restored viability on Krebs cycle substrates and ATP synthesis, but failed to restore ATP hydrolysis activity or inhibitor sensitivity. Co-expression of both ATP8 and ATP6 from the nucleus led to stable protein import, integration into Complex V, restored ATP hydrolysis/synthesis, oxygen consumption, and Complex V re-assembly.","method":"Allotopic expression in patient cybrid cells; ATP synthesis/hydrolysis assays; oxygen consumption measurement; Complex V immunoblotting; glycolytic/viability assays","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 1 / Strong — reconstitution of Complex V function by allotopic expression with multiple orthogonal functional assays","pmids":["27596602"],"is_preprint":false},{"year":2016,"finding":"In yeast mitochondria, translation of the bicistronic ATP8/ATP6 mRNA is repressed by Smt1p, an inner membrane protein that forms a complex with the ATP8/ATP6 mRNA (and also with COB mRNA). F1 ATPase availability is proposed to displace Smt1p and allow the Atp22p activator to promote translation, coupling ATP8 and ATP6 synthesis to F1 assembly.","method":"Affinity purification of tagged Smt1p followed by RT-PCR with gene-specific primers to detect associated mRNAs; genetic analysis of smt1 mutants; [35S]methionine incorporation assays","journal":"Molecular biology of the cell","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — affinity purification of RNA–protein complex plus genetic rescue experiments, single lab, yeast model","pmids":["26823015"],"is_preprint":false},{"year":2017,"finding":"In yeast mitochondria, Aep3p functions as a translation activator specifically for ATP8: temperature-sensitive aep3 mutants selectively block [35S]methionine incorporation into Atp8p at non-permissive temperature without affecting transcription or mRNA processing, and the defect is partially rescued by allotopic ATP8 in high-copy plasmid.","method":"[35S]methionine pulse labeling in yeast mitochondria; Northern blotting; allotopic rescue assay; temperature-sensitive mutant analysis","journal":"Molecular biology of the cell","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple genetic and biochemical methods in yeast model, single lab","pmids":["28404747"],"is_preprint":false},{"year":2023,"finding":"In yeast, the equivalent of the human MT-ATP8 m.8403T>C variant (changing a conserved residue in subunit 8) is not detrimental to ATP synthase function. Structural analysis of this and five other MT-ATP8 variants provides evidence that subunit 8 contributes to the membrane domain of ATP synthase and that substitutions at specific positions can have structural consequences for the complex.","method":"Yeast S. cerevisiae mutagenesis model; biochemical assays of mitochondrial ATP synthase function; structural modeling/in silico analysis","journal":"Scientific reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — combination of yeast biochemical data and structural analysis; in silico component lowers tier, but wet-lab yeast data confirm functional context","pmids":["37340059"],"is_preprint":false},{"year":2024,"finding":"Allotopic expression of ATP8 (re-engineered with a mitochondrial targeting sequence and expressed from the ROSA26 nuclear locus) in transgenic mice (C57BL/6J-mtFVB background) produced constitutive protein expression across all tested tissues, successful mitochondrial import, and incorporation into ATP synthase with activity comparable to non-transgenic controls, without negative effects on mitochondrial function, metabolism, or behavior.","method":"Transgenic mouse generation; Western blotting; mitochondrial fractionation; ATP synthase activity assay; metabolic/behavioral testing","journal":"Molecular therapy. Methods & clinical development","confidence":"High","confidence_rationale":"Tier 2 / Strong — in vivo allotopic expression with multiple orthogonal readouts (import, complex incorporation, activity assays) confirming functional integration","pmids":["39659757"],"is_preprint":false}],"current_model":"MT-ATP8 encodes subunit 8 (A6L/chargerin II) of the mitochondrial ATP synthase Fo domain, where it is present in 1:1 stoichiometry with the holoenzyme, oriented with its N-terminus exposed on the cytoplasmic face of the inner membrane and its C-terminal/charge-cluster regions buried in Fo; loss of ATP8 prevents proper Complex V holoenzyme assembly and abolishes ATP synthesis/hydrolysis activity, while its translation is coupled to F1 availability through translational regulatory factors (Smt1p repressor, Aep3p/Atp22p activators in yeast), and both allotopic nuclear expression and in vivo transgenic delivery can rescue ATP8-null mitochondrial dysfunction."},"narrative":{"mechanistic_narrative":"MT-ATP8 encodes subunit 8 (A6L/chargerin II), an integral component of the membrane-embedded Fo domain of the mitochondrial ATP synthase (Complex V) that is required for energy transduction and oxidative ATP synthesis [PMID:6301689, PMID:3113438, PMID:3360805]. The protein is the product of the URFA6L reading frame that overlaps ATP6, and was identified at the protein level by region-specific antibodies and direct peptide sequencing [PMID:6301689, PMID:3360805]. Within Fo it adopts a defined topology—its short N-terminus exposed on the cytoplasmic face of the inner membrane while its C-terminal and charge-cluster regions are buried in the membrane domain—and is present in 1:1 stoichiometry with the holoenzyme [PMID:2531582, PMID:2139330]. Loss of ATP8 through a homoplasmic nonsense mutation prevents assembly of the Complex V holoenzyme, leaving only ATP synthase subcomplexes with residual free F1-ATPase activity and abolishing normal Complex V function [PMID:17954552, PMID:21686774]. ATP8 function is essential for mitochondrial integrity and bioenergetics in vivo: a pathogenic murine Atp8 mutation causes fragmented mitochondria, increased ROS, reduced ATP, and impaired glucose-stimulated insulin secretion in pancreatic β-cells [PMID:22919063]. Allotopic nuclear expression of ATP8 restores ATP synthesis and viability, and co-expression with ATP6 fully reconstitutes Complex V assembly and ATP hydrolysis, with stable mitochondrial import and complex incorporation also achievable in transgenic mice [PMID:27596602, PMID:39659757]. In yeast, translation of the bicistronic ATP8/ATP6 mRNA is gated by the inner-membrane repressor Smt1p and the activator Atp22p/Aep3p, coupling subunit synthesis to F1 availability [PMID:26823015, PMID:28404747].","teleology":[{"year":1983,"claim":"Established that the overlapping URFA6L reading frame is actually translated into a real mitochondrial protein, converting a predicted ORF into a bona fide gene product.","evidence":"Immunoprecipitation of mitochondrial translation products with N- and C-terminal anti-peptide antibodies plus tryptic fingerprinting in HeLa cells","pmids":["6301689"],"confidence":"High","gaps":["Did not establish the protein's biochemical function","No localization within ATP synthase determined"]},{"year":1987,"claim":"Linked the URFA6L product (chargerin II) to active energy transduction, indicating it participates in coupling redox reactions to ATP synthesis rather than being a passive structural element.","evidence":"Antibody immunoinhibition of ATP–Pi exchange and reversed electron flow in energized vs non-energized rat liver mitoplasts","pmids":["3113438"],"confidence":"Medium","gaps":["Conformational coupling inferred indirectly from antibody inhibition","Mechanism of redox-linked conformational change unresolved","Single lab"]},{"year":1988,"claim":"Confirmed chargerin II and the ATP8/URFA6L product are the same protein by direct chemistry, cementing the protein identity established immunologically.","evidence":"HPLC purification, lysylendopeptidase digestion, and peptide sequencing of rat liver chargerin II matched to the predicted URFA6L sequence","pmids":["3360805"],"confidence":"High","gaps":["Did not map position within the synthase","Stoichiometry unknown at this point"]},{"year":1989,"claim":"Defined the membrane topology of ATP8 within Fo, showing an asymmetric arrangement with the N-terminus surface-exposed and the rest buried—key to understanding how it integrates into the complex.","evidence":"Region-specific antibody accessibility on submitochondrial particles and intact mitochondria before/after membrane disruption","pmids":["2531582"],"confidence":"Medium","gaps":["No atomic structure","Functional consequence of buried charge cluster not tested","Single lab"]},{"year":1990,"claim":"Quantified ATP8 as a 1:1 stoichiometric subunit of the holoenzyme, establishing it as an obligate single-copy component rather than a substoichiometric accessory.","evidence":"Radioimmunoassay of purified rat liver ATP synthase and submitochondrial particles","pmids":["2139330"],"confidence":"Medium","gaps":["Single immunochemical method","Did not address assembly role"]},{"year":2007,"claim":"Demonstrated that ATP8 is required for Complex V holoenzyme assembly in humans, providing the first causal disease link and showing its loss yields abortive subcomplexes.","evidence":"Transmitochondrial cybrids from a patient with homoplasmic m.8529G>A (p.Trp55X); BN-PAGE, in-gel ATP hydrolysis, and enzyme activity assays","pmids":["17954552","21686774"],"confidence":"High","gaps":["Precise assembly step requiring ATP8 not defined","Why free F1 activity persists not mechanistically explained"]},{"year":2012,"claim":"Showed ATP8 is required for normal mitochondrial morphology, redox balance, and tissue-level bioenergetic output in vivo, connecting subunit dysfunction to physiological β-cell phenotypes.","evidence":"Conplastic mouse strain carrying m.7778G>T Atp8 mutation; mitochondrial ROS, ATP, morphology, and glucose-stimulated insulin secretion assays","pmids":["22919063"],"confidence":"Medium","gaps":["Molecular mechanism linking subunit defect to ROS/morphology unclear","Single lab","Specific to one genetic background"]},{"year":2016,"claim":"Reconstituted Complex V function by nuclear allotopic expression, proving ATP8 can be imported and integrated, and revealing that full restoration of ATP hydrolysis requires co-expression with ATP6.","evidence":"Allotopic expression in ATP8-null patient cybrids; ATP synthesis/hydrolysis, oxygen consumption, and Complex V immunoblotting assays","pmids":["27596602"],"confidence":"High","gaps":["Why ATP8 alone restores synthesis but not hydrolysis not fully resolved","Import efficiency limits not defined"]},{"year":2016,"claim":"Identified a mitochondrial translational control circuit coupling ATP8/ATP6 synthesis to F1 availability via an inner-membrane repressor, explaining how subunit production is matched to assembly demand.","evidence":"Affinity purification of tagged Smt1p with RT-PCR detection of associated ATP8/ATP6 mRNA and genetic analysis of smt1 mutants in yeast","pmids":["26823015"],"confidence":"Medium","gaps":["F1-mediated displacement of Smt1p is a model, not directly demonstrated","No human ortholog identified","Yeast model"]},{"year":2017,"claim":"Identified Aep3p as an ATP8-specific translational activator, sharpening the picture of dedicated factors controlling subunit 8 synthesis.","evidence":"[35S]methionine pulse labeling in temperature-sensitive aep3 yeast mutants with Northern blotting and allotopic rescue","pmids":["28404747"],"confidence":"Medium","gaps":["Direct mRNA binding by Aep3p not shown","Human equivalent unknown","Yeast model"]},{"year":2023,"claim":"Used yeast modeling and structural analysis to discriminate benign from consequential MT-ATP8 variants, refining understanding of which residues matter for the membrane domain contribution.","evidence":"Yeast mutagenesis of conserved subunit 8 positions with ATP synthase activity assays and structural/in silico modeling","pmids":["37340059"],"confidence":"Medium","gaps":["In silico structural component not experimentally validated","Variant effects in human cells not tested for all positions"]},{"year":2024,"claim":"Demonstrated stable in vivo allotopic delivery of ATP8 in transgenic mice with successful import and complex incorporation, advancing a gene-therapy strategy without overt toxicity.","evidence":"Transgenic C57BL/6J-mtFVB mice expressing MTS-tagged ATP8 from ROSA26; Western blotting, mitochondrial fractionation, activity assays, metabolic/behavioral testing","pmids":["39659757"],"confidence":"High","gaps":["Rescue of an ATP8-null disease phenotype not tested in this model","Long-term and disease-context efficacy undetermined"]},{"year":null,"claim":"How ATP8 nucleates or stabilizes Complex V assembly at atomic resolution, and whether the yeast Smt1p/Aep3p translational control circuit has functional human counterparts, remain open.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No human structural model of ATP8 within assembled Fo from the corpus","No human translational regulators identified","Assembly intermediate requiring ATP8 not defined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0005198","term_label":"structural molecule activity","supporting_discovery_ids":[3,4,6]}],"localization":[{"term_id":"GO:0005739","term_label":"mitochondrion","supporting_discovery_ids":[0,1,3]}],"pathway":[{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[1,6,8]}],"complexes":["mitochondrial ATP synthase (Complex V) Fo domain"],"partners":["MT-ATP6","SMT1P","AEP3P","ATP22P"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"P03928","full_name":"ATP synthase F(0) complex subunit 8","aliases":["A6L","F-ATPase subunit 8"],"length_aa":68,"mass_kda":8.0,"function":"Subunit 8, of the mitochondrial membrane ATP synthase complex (F(1)F(0) ATP synthase or Complex V) that produces ATP from ADP in the presence of a proton gradient across the membrane which is generated by electron transport complexes of the respiratory chain (PubMed:37244256). ATP synthase complex consist of a soluble F(1) head domain - the catalytic core - and a membrane F(1) domain - the membrane proton channel (PubMed:37244256). These two domains are linked by a central stalk rotating inside the F(1) region and a stationary peripheral stalk (PubMed:37244256). During catalysis, ATP synthesis in the catalytic domain of F(1) is coupled via a rotary mechanism of the central stalk subunits to proton translocation (Probable). In vivo, can only synthesize ATP although its ATP hydrolase activity can be activated artificially in vitro (By similarity). Part of the complex F(0) domain (PubMed:37244256)","subcellular_location":"Mitochondrion membrane","url":"https://www.uniprot.org/uniprotkb/P03928/entry"},"depmap":{"release":"DepMap","has_data":false,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/MT-ATP8"},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/MT-ATP8","total_profiled":1310},"omim":[{"mim_id":"621431","title":"MITOCHONDRIAL COMPLEX IV DEFICIENCY, NUCLEAR TYPE 24; MC4DN24","url":"https://www.omim.org/entry/621431"},{"mim_id":"614272","title":"FAST KINASE DOMAINS 5; FASTKD5","url":"https://www.omim.org/entry/614272"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in all","driving_tissues":[{"tissue":"heart muscle","ntpm":355486.2}],"url":"https://www.proteinatlas.org/search/MT-ATP8"},"hgnc":{"alias_symbol":["ATP8","A6L","URFA6L"],"prev_symbol":["MTATP8"]},"alphafold":{"accession":"P03928","domains":[{"cath_id":"-","chopping":"6-62","consensus_level":"medium","plddt":74.6505,"start":6,"end":62}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/P03928","model_url":"https://alphafold.ebi.ac.uk/files/AF-P03928-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-P03928-F1-predicted_aligned_error_v6.png","plddt_mean":73.62},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=MT-ATP8","jax_strain_url":"https://www.jax.org/strain/search?query=MT-ATP8"},"sequence":{"accession":"P03928","fasta_url":"https://rest.uniprot.org/uniprotkb/P03928.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/P03928/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/P03928"}},"corpus_meta":[{"pmid":"11156984","id":"PMC_11156984","title":"Trichinella spiralis 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nanoparticle delivery of the CRISPR/Cas9 system directly into the mitochondria of cells carrying m.7778G>T mutation in MtDNA (mt-Atp8).","date":"2025","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/40537532","citation_count":11,"is_preprint":false},{"pmid":"23735083","id":"PMC_23735083","title":"A novel ATP8 gene mutation in an infant with tetralogy of Fallot.","date":"2013","source":"Cardiology in the young","url":"https://pubmed.ncbi.nlm.nih.gov/23735083","citation_count":11,"is_preprint":false},{"pmid":"15692730","id":"PMC_15692730","title":"Mitochondrial ATP synthase: a bioinformatic approach reveals new insights about the roles of supernumerary subunits g and A6L.","date":"2004","source":"Journal of bioenergetics and biomembranes","url":"https://pubmed.ncbi.nlm.nih.gov/15692730","citation_count":11,"is_preprint":false},{"pmid":"40112238","id":"PMC_40112238","title":"Natural History of Patients With Mitochondrial ATPase Deficiency Due to Pathogenic Variants of 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different zones: detecting the signature of natural selection on mitochondrial genome].","date":"2009","source":"Yi chuan = Hereditas","url":"https://pubmed.ncbi.nlm.nih.gov/19273422","citation_count":6,"is_preprint":false},{"pmid":"34678134","id":"PMC_34678134","title":"Genetic differentiation of Indian dromedary and Bactrian camel populations based on mitochondrial ATP8 and ATP6 genes.","date":"2021","source":"Animal biotechnology","url":"https://pubmed.ncbi.nlm.nih.gov/34678134","citation_count":5,"is_preprint":false},{"pmid":"16550397","id":"PMC_16550397","title":"Petaloid-type cms in carrot is not associated with expression of atp8 (orfB).","date":"2006","source":"TAG. 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Theoretische und angewandte Genetik","url":"https://pubmed.ncbi.nlm.nih.gov/16550397","citation_count":5,"is_preprint":false},{"pmid":"37340059","id":"PMC_37340059","title":"Analysis of MT-ATP8 gene variants reported in patients by modeling in silico and in yeast model organism.","date":"2023","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/37340059","citation_count":4,"is_preprint":false},{"pmid":"36066780","id":"PMC_36066780","title":"A lack of a definite correlation between male sub-fertility and single nucleotide polymorphisms in sperm mitochondrial genes MT-CO3, MT-ATP6 and MT-ATP8.","date":"2022","source":"Molecular biology reports","url":"https://pubmed.ncbi.nlm.nih.gov/36066780","citation_count":3,"is_preprint":false},{"pmid":"34435125","id":"PMC_34435125","title":"The complete mitogenome of the inarticulate brachiopod Glottidia pyramidata reveals insights into gene order variation, deviant ATP8 and mtORFans in the Brachiopoda.","date":"2021","source":"Mitochondrial DNA. 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Part B, Resources","url":"https://pubmed.ncbi.nlm.nih.gov/33474428","citation_count":1,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.05.13.653780","title":"Mitochondrial Genome of the lesser known - Madras Hedgehog (  <i>Paraechinus nudiventris</i>  ): Genomic characterization and comparative analysis within Erinaceidae","date":"2025-05-16","source":"bioRxiv","url":"https://doi.org/10.1101/2025.05.13.653780","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.07.01.662465","title":"Mitochondrial Genome-Based Phylogeny of Turbellarians and Evidence for Accelerated Mitochondrial Evolution in Symbiotic Species","date":"2025-07-04","source":"bioRxiv","url":"https://doi.org/10.1101/2025.07.01.662465","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.02.07.636106","title":"EndoMAP.v1, a Structural Protein Complex Landscape of Human Endosomes","date":"2025-02-09","source":"bioRxiv","url":"https://doi.org/10.1101/2025.02.07.636106","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.11.18.624032","title":"A phased chromosome-level genome of the annelid tubeworm  <i>Galeolaria caespitosa</i>","date":"2024-11-20","source":"bioRxiv","url":"https://doi.org/10.1101/2024.11.18.624032","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.08.21.609022","title":"The complete mitochondrial genome of  <i>Heikeopsis japonica</i>  (Decapoda: Brachyura: Dorippidae): Phylogenetic implications of the family Dorippidae","date":"2024-08-22","source":"bioRxiv","url":"https://doi.org/10.1101/2024.08.21.609022","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":26104,"output_tokens":3212,"usd":0.063246,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":10886,"output_tokens":3757,"usd":0.074177,"stage2_stop_reason":"end_turn"},"total_usd":0.137423,"stage1_batch_id":"msgbatch_01BbTCMyrRPyhtEq6b1MdwCN","stage2_batch_id":"msgbatch_011dEed5bbxYvTAaQWKJevxu","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1983,\n      \"finding\": \"The unidentified reading frame A6L (URFA6L), overlapping the ATPase 6 gene, is expressed as a protein (protein #25) in human mitochondria. Antibodies against synthetic peptides corresponding to both the NH2-terminal and COOH-terminal sequences of the predicted A6L polypeptide immunoprecipitated a specific mitochondrial translation product from HeLa cells, and trypsin fingerprinting was consistent with the identification.\",\n      \"method\": \"Immunoprecipitation with anti-synthetic-peptide antibodies; tryptic fingerprinting of mitochondrial translation products\",\n      \"journal\": \"Cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — direct protein identification by two independent antibodies (N- and C-terminal peptides) plus peptide fingerprinting in a landmark study\",\n      \"pmids\": [\"6301689\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1987,\n      \"finding\": \"Chargerin II (the URFA6L / ATP8 product) is required for energy transduction in rat liver mitochondria: antibody against chargerin II inhibited ATP–Pi exchange and reversed electron flow from succinate to NAD in mitoplasts, with greater inhibition in the energized state, indicating a conformational change coupled to redox reactions.\",\n      \"method\": \"Immunoinhibition assays in energized and non-energized mitoplasts; ATP–Pi exchange and reversed electron flow measurements\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional antibody inhibition experiments with multiple assay readouts, single lab\",\n      \"pmids\": [\"3113438\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1988,\n      \"finding\": \"Chargerin II purified from rat liver mitochondria was identified as the product of URFA6L (ATP8). Peptide sequencing of HPLC-purified chargerin II yielded 12 amino acids highly homologous to the predicted C-terminal sequence of the URFA6L polypeptide, and amino acid composition matched the predicted protein.\",\n      \"method\": \"HPLC purification from mitochondria; lysylendopeptidase digestion; peptide sequencing; amino acid composition analysis; Western blotting\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — direct purification and peptide sequencing establishing the identity of the protein product, replicated conceptually with earlier antibody work\",\n      \"pmids\": [\"3360805\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1989,\n      \"finding\": \"The orientation of chargerin II (ATP8/A6L) within the Fo sector of rat liver mitochondrial ATP synthase was determined: its N-terminal ~8 residues are exposed on the cytoplasmic (C-side) surface of Fo, while the C-terminal and charge-cluster regions are buried within Fo.\",\n      \"method\": \"Antibodies against N-terminal and C-terminal peptides applied to submitochondrial particles and intact mitochondria; immunoreactivity probed before and after membrane disruption\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — topology probed with region-specific antibodies in defined membrane orientation, single lab\",\n      \"pmids\": [\"2531582\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1990,\n      \"finding\": \"Chargerin II (ATP8) is present in the H+-ATP synthase of rat liver mitochondria in a 1:1 molar stoichiometry relative to the holoenzyme, as determined by radioimmunoassay of purified ATP synthase and submitochondrial particles.\",\n      \"method\": \"Radioimmunoassay of purified ATP synthase and submitochondrial particles\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — quantitative stoichiometry from a single lab using a single immunochemical method\",\n      \"pmids\": [\"2139330\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"Bioinformatic sequence analysis of A6L (ATP8) across vertebrates identified a conserved aromatic residue adjacent to the N-terminal MPQL motif (MPQLX4Ar motif), proposed as functionally important for the role of A6L in the Fo membrane domain of ATP synthase.\",\n      \"method\": \"Comparative sequence alignment and homology searching\",\n      \"journal\": \"Journal of bioenergetics and biomembranes\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 4 / Weak — computational/bioinformatic prediction only, no experimental validation reported\",\n      \"pmids\": [\"15692730\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"A homoplasmic nonsense mutation m.8529G>A (p.Trp55X) in the mitochondrial ATP8 gene causes loss of ATP8 protein, failure to assemble Complex V holoenzyme, reduced Complex V activity, and accumulation of ATP synthase subcomplexes with residual free F1-ATPase activity. Demonstrated in patient fibroblasts, muscle, and transmitochondrial cybrid clones.\",\n      \"method\": \"Transmitochondrial cybrid generation; Blue Native PAGE with immunoblotting; in-gel ATP hydrolysis activity assay; enzyme activity measurements in fibroblasts and muscle\",\n      \"journal\": \"Journal of medical genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (cybrid validation, BN-PAGE, activity assay) in patient-derived and cybrid cells; independently replicated in case report PMID 21686774\",\n      \"pmids\": [\"17954552\", \"21686774\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"A point mutation in the murine Atp8 gene (m.7778G>T in B6-mtFVB mice) causes fragmented mitochondrial morphology, increased mitochondrial ROS generation, reduced cellular ATP levels, impaired glucose-induced insulin secretion in pancreatic islets, and higher susceptibility to palmitate stress, establishing ATP8 as required for normal β-cell mitochondrial function and secretory responsiveness.\",\n      \"method\": \"Conplastic mouse strain comparison; mitochondrial ROS measurement; ATP level assay; glucose-stimulated insulin secretion assay; morphological analysis of isolated islets\",\n      \"journal\": \"Endocrinology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic model with multiple cellular readouts, single lab\",\n      \"pmids\": [\"22919063\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"Nuclear (allotopic) expression of ATP8 alone (with a mitochondrial targeting sequence) in ATP8-null cybrid cells restored viability on Krebs cycle substrates and ATP synthesis, but failed to restore ATP hydrolysis activity or inhibitor sensitivity. Co-expression of both ATP8 and ATP6 from the nucleus led to stable protein import, integration into Complex V, restored ATP hydrolysis/synthesis, oxygen consumption, and Complex V re-assembly.\",\n      \"method\": \"Allotopic expression in patient cybrid cells; ATP synthesis/hydrolysis assays; oxygen consumption measurement; Complex V immunoblotting; glycolytic/viability assays\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — reconstitution of Complex V function by allotopic expression with multiple orthogonal functional assays\",\n      \"pmids\": [\"27596602\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"In yeast mitochondria, translation of the bicistronic ATP8/ATP6 mRNA is repressed by Smt1p, an inner membrane protein that forms a complex with the ATP8/ATP6 mRNA (and also with COB mRNA). F1 ATPase availability is proposed to displace Smt1p and allow the Atp22p activator to promote translation, coupling ATP8 and ATP6 synthesis to F1 assembly.\",\n      \"method\": \"Affinity purification of tagged Smt1p followed by RT-PCR with gene-specific primers to detect associated mRNAs; genetic analysis of smt1 mutants; [35S]methionine incorporation assays\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — affinity purification of RNA–protein complex plus genetic rescue experiments, single lab, yeast model\",\n      \"pmids\": [\"26823015\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"In yeast mitochondria, Aep3p functions as a translation activator specifically for ATP8: temperature-sensitive aep3 mutants selectively block [35S]methionine incorporation into Atp8p at non-permissive temperature without affecting transcription or mRNA processing, and the defect is partially rescued by allotopic ATP8 in high-copy plasmid.\",\n      \"method\": \"[35S]methionine pulse labeling in yeast mitochondria; Northern blotting; allotopic rescue assay; temperature-sensitive mutant analysis\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple genetic and biochemical methods in yeast model, single lab\",\n      \"pmids\": [\"28404747\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"In yeast, the equivalent of the human MT-ATP8 m.8403T>C variant (changing a conserved residue in subunit 8) is not detrimental to ATP synthase function. Structural analysis of this and five other MT-ATP8 variants provides evidence that subunit 8 contributes to the membrane domain of ATP synthase and that substitutions at specific positions can have structural consequences for the complex.\",\n      \"method\": \"Yeast S. cerevisiae mutagenesis model; biochemical assays of mitochondrial ATP synthase function; structural modeling/in silico analysis\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — combination of yeast biochemical data and structural analysis; in silico component lowers tier, but wet-lab yeast data confirm functional context\",\n      \"pmids\": [\"37340059\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Allotopic expression of ATP8 (re-engineered with a mitochondrial targeting sequence and expressed from the ROSA26 nuclear locus) in transgenic mice (C57BL/6J-mtFVB background) produced constitutive protein expression across all tested tissues, successful mitochondrial import, and incorporation into ATP synthase with activity comparable to non-transgenic controls, without negative effects on mitochondrial function, metabolism, or behavior.\",\n      \"method\": \"Transgenic mouse generation; Western blotting; mitochondrial fractionation; ATP synthase activity assay; metabolic/behavioral testing\",\n      \"journal\": \"Molecular therapy. Methods & clinical development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — in vivo allotopic expression with multiple orthogonal readouts (import, complex incorporation, activity assays) confirming functional integration\",\n      \"pmids\": [\"39659757\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"MT-ATP8 encodes subunit 8 (A6L/chargerin II) of the mitochondrial ATP synthase Fo domain, where it is present in 1:1 stoichiometry with the holoenzyme, oriented with its N-terminus exposed on the cytoplasmic face of the inner membrane and its C-terminal/charge-cluster regions buried in Fo; loss of ATP8 prevents proper Complex V holoenzyme assembly and abolishes ATP synthesis/hydrolysis activity, while its translation is coupled to F1 availability through translational regulatory factors (Smt1p repressor, Aep3p/Atp22p activators in yeast), and both allotopic nuclear expression and in vivo transgenic delivery can rescue ATP8-null mitochondrial dysfunction.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"MT-ATP8 encodes subunit 8 (A6L/chargerin II), an integral component of the membrane-embedded Fo domain of the mitochondrial ATP synthase (Complex V) that is required for energy transduction and oxidative ATP synthesis [#0, #1, #2]. The protein is the product of the URFA6L reading frame that overlaps ATP6, and was identified at the protein level by region-specific antibodies and direct peptide sequencing [#0, #2]. Within Fo it adopts a defined topology—its short N-terminus exposed on the cytoplasmic face of the inner membrane while its C-terminal and charge-cluster regions are buried in the membrane domain—and is present in 1:1 stoichiometry with the holoenzyme [#3, #4]. Loss of ATP8 through a homoplasmic nonsense mutation prevents assembly of the Complex V holoenzyme, leaving only ATP synthase subcomplexes with residual free F1-ATPase activity and abolishing normal Complex V function [#6]. ATP8 function is essential for mitochondrial integrity and bioenergetics in vivo: a pathogenic murine Atp8 mutation causes fragmented mitochondria, increased ROS, reduced ATP, and impaired glucose-stimulated insulin secretion in pancreatic β-cells [#7]. Allotopic nuclear expression of ATP8 restores ATP synthesis and viability, and co-expression with ATP6 fully reconstitutes Complex V assembly and ATP hydrolysis, with stable mitochondrial import and complex incorporation also achievable in transgenic mice [#8, #12]. In yeast, translation of the bicistronic ATP8/ATP6 mRNA is gated by the inner-membrane repressor Smt1p and the activator Atp22p/Aep3p, coupling subunit synthesis to F1 availability [#9, #10].\",\n  \"teleology\": [\n    {\n      \"year\": 1983,\n      \"claim\": \"Established that the overlapping URFA6L reading frame is actually translated into a real mitochondrial protein, converting a predicted ORF into a bona fide gene product.\",\n      \"evidence\": \"Immunoprecipitation of mitochondrial translation products with N- and C-terminal anti-peptide antibodies plus tryptic fingerprinting in HeLa cells\",\n      \"pmids\": [\"6301689\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not establish the protein's biochemical function\", \"No localization within ATP synthase determined\"]\n    },\n    {\n      \"year\": 1987,\n      \"claim\": \"Linked the URFA6L product (chargerin II) to active energy transduction, indicating it participates in coupling redox reactions to ATP synthesis rather than being a passive structural element.\",\n      \"evidence\": \"Antibody immunoinhibition of ATP–Pi exchange and reversed electron flow in energized vs non-energized rat liver mitoplasts\",\n      \"pmids\": [\"3113438\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Conformational coupling inferred indirectly from antibody inhibition\", \"Mechanism of redox-linked conformational change unresolved\", \"Single lab\"]\n    },\n    {\n      \"year\": 1988,\n      \"claim\": \"Confirmed chargerin II and the ATP8/URFA6L product are the same protein by direct chemistry, cementing the protein identity established immunologically.\",\n      \"evidence\": \"HPLC purification, lysylendopeptidase digestion, and peptide sequencing of rat liver chargerin II matched to the predicted URFA6L sequence\",\n      \"pmids\": [\"3360805\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not map position within the synthase\", \"Stoichiometry unknown at this point\"]\n    },\n    {\n      \"year\": 1989,\n      \"claim\": \"Defined the membrane topology of ATP8 within Fo, showing an asymmetric arrangement with the N-terminus surface-exposed and the rest buried—key to understanding how it integrates into the complex.\",\n      \"evidence\": \"Region-specific antibody accessibility on submitochondrial particles and intact mitochondria before/after membrane disruption\",\n      \"pmids\": [\"2531582\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No atomic structure\", \"Functional consequence of buried charge cluster not tested\", \"Single lab\"]\n    },\n    {\n      \"year\": 1990,\n      \"claim\": \"Quantified ATP8 as a 1:1 stoichiometric subunit of the holoenzyme, establishing it as an obligate single-copy component rather than a substoichiometric accessory.\",\n      \"evidence\": \"Radioimmunoassay of purified rat liver ATP synthase and submitochondrial particles\",\n      \"pmids\": [\"2139330\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single immunochemical method\", \"Did not address assembly role\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Demonstrated that ATP8 is required for Complex V holoenzyme assembly in humans, providing the first causal disease link and showing its loss yields abortive subcomplexes.\",\n      \"evidence\": \"Transmitochondrial cybrids from a patient with homoplasmic m.8529G>A (p.Trp55X); BN-PAGE, in-gel ATP hydrolysis, and enzyme activity assays\",\n      \"pmids\": [\"17954552\", \"21686774\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Precise assembly step requiring ATP8 not defined\", \"Why free F1 activity persists not mechanistically explained\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Showed ATP8 is required for normal mitochondrial morphology, redox balance, and tissue-level bioenergetic output in vivo, connecting subunit dysfunction to physiological β-cell phenotypes.\",\n      \"evidence\": \"Conplastic mouse strain carrying m.7778G>T Atp8 mutation; mitochondrial ROS, ATP, morphology, and glucose-stimulated insulin secretion assays\",\n      \"pmids\": [\"22919063\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular mechanism linking subunit defect to ROS/morphology unclear\", \"Single lab\", \"Specific to one genetic background\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Reconstituted Complex V function by nuclear allotopic expression, proving ATP8 can be imported and integrated, and revealing that full restoration of ATP hydrolysis requires co-expression with ATP6.\",\n      \"evidence\": \"Allotopic expression in ATP8-null patient cybrids; ATP synthesis/hydrolysis, oxygen consumption, and Complex V immunoblotting assays\",\n      \"pmids\": [\"27596602\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Why ATP8 alone restores synthesis but not hydrolysis not fully resolved\", \"Import efficiency limits not defined\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Identified a mitochondrial translational control circuit coupling ATP8/ATP6 synthesis to F1 availability via an inner-membrane repressor, explaining how subunit production is matched to assembly demand.\",\n      \"evidence\": \"Affinity purification of tagged Smt1p with RT-PCR detection of associated ATP8/ATP6 mRNA and genetic analysis of smt1 mutants in yeast\",\n      \"pmids\": [\"26823015\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"F1-mediated displacement of Smt1p is a model, not directly demonstrated\", \"No human ortholog identified\", \"Yeast model\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Identified Aep3p as an ATP8-specific translational activator, sharpening the picture of dedicated factors controlling subunit 8 synthesis.\",\n      \"evidence\": \"[35S]methionine pulse labeling in temperature-sensitive aep3 yeast mutants with Northern blotting and allotopic rescue\",\n      \"pmids\": [\"28404747\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct mRNA binding by Aep3p not shown\", \"Human equivalent unknown\", \"Yeast model\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Used yeast modeling and structural analysis to discriminate benign from consequential MT-ATP8 variants, refining understanding of which residues matter for the membrane domain contribution.\",\n      \"evidence\": \"Yeast mutagenesis of conserved subunit 8 positions with ATP synthase activity assays and structural/in silico modeling\",\n      \"pmids\": [\"37340059\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"In silico structural component not experimentally validated\", \"Variant effects in human cells not tested for all positions\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Demonstrated stable in vivo allotopic delivery of ATP8 in transgenic mice with successful import and complex incorporation, advancing a gene-therapy strategy without overt toxicity.\",\n      \"evidence\": \"Transgenic C57BL/6J-mtFVB mice expressing MTS-tagged ATP8 from ROSA26; Western blotting, mitochondrial fractionation, activity assays, metabolic/behavioral testing\",\n      \"pmids\": [\"39659757\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Rescue of an ATP8-null disease phenotype not tested in this model\", \"Long-term and disease-context efficacy undetermined\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How ATP8 nucleates or stabilizes Complex V assembly at atomic resolution, and whether the yeast Smt1p/Aep3p translational control circuit has functional human counterparts, remain open.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No human structural model of ATP8 within assembled Fo from the corpus\", \"No human translational regulators identified\", \"Assembly intermediate requiring ATP8 not defined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005198\", \"supporting_discovery_ids\": [3, 4, 6]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [0, 1, 3]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [1, 6, 8]}\n    ],\n    \"complexes\": [\n      \"mitochondrial ATP synthase (Complex V) Fo domain\"\n    ],\n    \"partners\": [\n      \"MT-ATP6\",\n      \"Smt1p\",\n      \"Aep3p\",\n      \"Atp22p\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}