{"gene":"COX14","run_date":"2026-04-28T17:28:53","timeline":{"discoveries":[{"year":1995,"finding":"COX14 encodes a low molecular mass protein (~8 kDa) that localizes to the mitochondrial membrane and is associated with a high molecular weight complex; loss of COX14 results in a cytochrome oxidase assembly-arrested phenotype despite normal synthesis of mitochondrially encoded COX subunits, establishing COX14 as a COX assembly factor acting at a late stage of the pathway.","method":"Complementation cloning, Western analysis, biotinylated gene fusion localization, cytochrome oxidase activity assay","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 — original cloning paper with multiple orthogonal methods and functional validation via complementation","pmids":["7797555"],"is_preprint":false},{"year":2004,"finding":"Cox14p and Mss51p (a COX1 mRNA translational activator) interact with each other and with newly synthesized Cox1p to form a transient Cox14p–Cox1p–Mss51p assembly intermediate complex; this complex functions to downregulate Cox1p synthesis (sequestering Mss51p), and deletion of COX14 alone does not reduce Cox1p synthesis because the sequestration complex fails to form.","method":"Co-immunoprecipitation, pulse-labeling of mitochondrial translation products, genetic epistasis (cox14 null combined with other COX mutants and mss51 suppressor mutations)","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 2 — reciprocal Co-IP plus genetic epistasis, replicated by multiple subsequent labs","pmids":["15306853"],"is_preprint":false},{"year":2007,"finding":"Shy1 (yeast SURF1 ortholog) interacts with Mss51 and Cox14 in translational regulatory complexes and also associates with later COX assembly subcomplexes; Cox14-containing partially assembled COX complexes can associate with the bc1 complex to form transitional supercomplexes, linking Cox1 translational regulation to supercomplex formation.","method":"Co-immunoprecipitation, native gel electrophoresis (BN-PAGE), affinity purification, mass spectrometry","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods (Co-IP, BN-PAGE, MS) in a single study with strong mechanistic follow-up","pmids":["17882259"],"is_preprint":false},{"year":2009,"finding":"Mss51 does not stably interact with newly synthesized Cox1 in a cox14 null mutant, demonstrating that Cox14 is required for sequestration of Mss51 in early COX assembly intermediates; the Mss51–Cox14 physical interaction depends on the presence of newly synthesized Cox1, indicating dynamic assembly of Cox1-nucleated early intermediates.","method":"Co-immunoprecipitation of newly synthesized Cox1, pulse-labeling, ARG8m reporter assay for translational output","journal":"Molecular biology of the cell","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods, mechanistically rigorous, consistent with prior and subsequent work","pmids":["19710419"],"is_preprint":false},{"year":2010,"finding":"Coa3 and Cox14 together form early COX assembly intermediates with newly synthesized Cox1 and are both required for Mss51 association with these complexes; Mss51 exists in equilibrium between a latent (translational resting) state and a committed (translation-effective) state represented as distinct complexes, and Coa3/Cox14 promote formation of the latent state to downregulate COX1 expression; Coa1 binding to Mss51 in complex with Cox14, Coa3, and Cox1 is essential for full Mss51 inactivation.","method":"Co-immunoprecipitation, pulse-labeling, BN-PAGE, identification of novel assembly factor Coa3 (Yjl062w-A) by mass spectrometry","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal biochemical methods, novel factor identification, consistent with prior epistasis data","pmids":["20876281"],"is_preprint":false},{"year":2010,"finding":"Deletion of the C-terminal 11 or 15 residues of Cox1 eliminates assembly-feedback control of Cox1 synthesis and reduces the strength of the Mss51–Cox14 interaction, establishing that the Cox1 C-terminal domain is required for Mss51 sequestration via Cox14 in early assembly intermediates.","method":"Site-directed mutagenesis of mtDNA, co-immunoprecipitation, pulse-labeling, ARG8m reporter assay","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1/2 — mutagenesis combined with Co-IP and translational reporter, mechanistically informative","pmids":["20807763"],"is_preprint":false},{"year":2010,"finding":"Cox25 is an inner mitochondrial membrane protein that is an essential component of the Cox1–Ssc1–Mss51–Cox14 early assembly complex; after Ssc1–Mss51 release, Cox25 continues to interact with Cox14 and Cox1 to facilitate formation of multisubunit COX assembly intermediates and also interacts with Shy1 and Cox5 in a separate Mss51-free complex.","method":"Co-immunoprecipitation, BN-PAGE, pulse-labeling, genetic epistasis (cox25 null phenotype)","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods, novel interactor identified, mechanistic follow-up provided","pmids":["21068384"],"is_preprint":false},{"year":2012,"finding":"C12orf62 (human ortholog of yeast COX14, also called COX14 in humans) is a small (~6 kDa) single-transmembrane protein that localizes to mitochondria, co-immunoprecipitates with COX I, COX II, and COX IV, and is required for coupling early COX assembly steps with COX I synthesis; loss-of-function mutations cause COX-assembly defects with specific decrease in COX I synthesis and fatal neonatal lactic acidosis.","method":"Microcell-mediated chromosome transfer, homozygosity mapping, siRNA knockdown, retroviral rescue, co-immunoprecipitation with epitope-tagged C12orf62, 2D BN-PAGE of newly synthesized subunits, immunoblot","journal":"American journal of human genetics","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods including patient mutations, rescue, Co-IP, and metabolic labeling","pmids":["22243966"],"is_preprint":false},{"year":2012,"finding":"Iterative orthology prediction (Ortho-Profile) confirmed that human C12orf62 is the functional ortholog of yeast COX14; experimental validation of subcellular localization to mitochondria and co-purification with human COX-associated proteins confirmed its role in negative regulation of COX I translation.","method":"Bioinformatic orthology prediction validated by experimental co-purification and localization studies","journal":"Genome biology","confidence":"Medium","confidence_rationale":"Tier 3 — orthology confirmed by co-purification and localization, functional validation derived from companion paper","pmids":["22356826"],"is_preprint":false},{"year":2015,"finding":"COX14 (C12orf62) and COA3 are mutually interdependent for their stability: COX14 protein is undetectable in COA3-deficient patient fibroblasts and COA3 is undetectable in COX14-deficient fibroblasts, demonstrating that they form a co-dependent early COX assembly complex containing COX1.","method":"Immunoblot analysis of patient fibroblasts with COA3 or COX14 mutations, BN-PAGE, pulse-labeling, retroviral rescue","journal":"Journal of medical genetics","confidence":"High","confidence_rationale":"Tier 2 — reciprocal protein stability analysis in human patient cells with rescue experiments","pmids":["25604084"],"is_preprint":false},{"year":2016,"finding":"Human mitochondrial ribosomes translating COX1 mRNA selectively engage with cytochrome c oxidase assembly factors (including COX14) in the inner membrane; COX assembly defects arrest mitochondrial translation in a ribosome–nascent chain complex with partially membrane-inserted COX1, establishing a translational plasticity pathway in which COX14 participates in coupling synthesis to assembly.","method":"Ribosome nascent chain complex isolation, BN-PAGE, quantitative mass spectrometry (SILAC), siRNA knockdown, pulse-labeling","journal":"Cell","confidence":"High","confidence_rationale":"Tier 2 — rigorous biochemical isolation of ribosome-nascent chain complexes with quantitative MS, multiple orthogonal methods","pmids":["27693358"],"is_preprint":false},{"year":2017,"finding":"CMC1 forms an early COX assembly intermediate with COX1, COA3, and COX14; CMC1 knockout shows normal COX1 synthesis but decreased COX activity due to instability of newly synthesized COX1, and CMC1 stabilizes the COX1–COA3–COX14 complex prior to incorporation of COX4 and COX5a; CMC1 acts independently of COX10, COX11, SURF1 (metallation/late stability factors), indicating a distinct role for the COX14-containing early complex.","method":"TALEN-mediated knockout, BN-PAGE, co-immunoprecipitation, pulse-labeling, immunoblot","journal":"EMBO reports","confidence":"High","confidence_rationale":"Tier 2 — genetic KO with multiple biochemical readouts and epistatic dissection of assembly pathway","pmids":["28082314"],"is_preprint":false},{"year":2017,"finding":"Cox1 C-terminal mutations (P521A/P522A and V524E) disrupt the regulatory role of the Cox1 C-terminus by reducing binding of Mss51 and Cox14 to COA complexes, enriching Mss51 in a translationally active form and maintaining full Cox1 synthesis even when COX assembly is blocked; this confirms that the Cox1 C-terminal domain directly mediates the Mss51–Cox14 interaction within assembly intermediates.","method":"Site-directed mutagenesis of mitochondrial COX1 gene, co-immunoprecipitation, BN-PAGE, pulse-labeling","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1/2 — mutagenesis with Co-IP and translational assays, mechanistically rigorous","pmids":["28490636"],"is_preprint":false},{"year":2017,"finding":"Mitospecific ribosomal protein MrpL35, together with Mrp7, coordinates Cox1 synthesis with COX assembly in a manner requiring Cox14 and Coa3, indicating that the mitoribosome communicates with the Cox14/Coa3 early assembly module.","method":"Genetic analysis of mrpL35 mutants, co-immunoprecipitation, pulse-labeling, epistasis with cox14 deletion","journal":"Molecular biology of the cell","confidence":"Medium","confidence_rationale":"Tier 2 — genetic and biochemical evidence but cox14 involvement is epistatic inference, not direct interaction demonstrated","pmids":["28931599"],"is_preprint":false},{"year":2024,"finding":"A COX14 M19I missense mouse model corresponding to a human complex IV deficiency patient shows that COX14 is required for COX1 translation in vivo; loss of COX14 function triggers release of mitochondrial RNA into the cytosol (sensed by the RIG-1 pathway), driven by increased reactive oxygen species from complex IV deficiency, leading to tissue-specific liver inflammation.","method":"COX14 M19I knock-in mouse model, pulse-labeling of mitochondrial translation, ROS measurements, cytosolic mtRNA detection, RIG-1 pathway activation assays, comparison with COA3 Y72C mouse model","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 — in vivo mouse model with multiple orthogonal functional readouts; companion COA3 model provides epistatic validation","pmids":["39134548"],"is_preprint":false}],"current_model":"COX14 (yeast) / C12orf62 (human COX14) encodes a small (~6–8 kDa) single-pass inner mitochondrial membrane protein that forms an early cytochrome c oxidase (COX/complex IV) assembly intermediate together with newly synthesized COX1, COA3, CMC1, and the translational activator/chaperone Mss51; within this complex, COX14 sequesters Mss51 in a latent, translation-incompetent state (dependent on the Cox1 C-terminal domain), thereby creating a negative feedback loop that couples COX1 mRNA translation to the availability and progress of COX assembly—when assembly is blocked, Mss51 remains trapped in the COX14-containing intermediate and COX1 synthesis is reduced, whereas deletion of COX14 releases Mss51 and de-represses Cox1 synthesis; in humans, loss of COX14 function impairs COX1 translation, destabilizes the COX assembly process, and triggers ROS-driven release of mitochondrial RNA into the cytosol, activating RIG-1–mediated inflammation in a tissue-specific manner."},"narrative":{"teleology":[{"year":1995,"claim":"Identification of COX14 as a mitochondrial membrane-associated COX assembly factor established that a small protein is required for cytochrome oxidase biogenesis despite normal mitochondrial translation of COX subunits.","evidence":"Complementation cloning, Western blot, and cytochrome oxidase activity assays in yeast","pmids":["7797555"],"confidence":"High","gaps":["Mechanism by which COX14 promotes assembly was unknown","Position in the assembly pathway (early vs. late) was not resolved","No interacting partners identified"]},{"year":2004,"claim":"Discovery that Cox14 forms a transient complex with newly synthesized Cox1 and the translational activator Mss51 revealed a feedback mechanism in which Cox14 sequesters Mss51 to downregulate Cox1 synthesis when assembly stalls.","evidence":"Reciprocal co-immunoprecipitation, pulse-labeling, and genetic epistasis in yeast","pmids":["15306853"],"confidence":"High","gaps":["Whether additional factors participate in the early assembly intermediate was unknown","The molecular determinant on Cox1 mediating the interaction was unidentified","Whether this feedback loop is conserved in mammals was untested"]},{"year":2007,"claim":"Demonstration that Shy1 (SURF1 ortholog) associates with Cox14-containing complexes and that these partially assembled intermediates form transitional supercomplexes with complex III linked COX14-mediated early assembly to later stages of respiratory chain organization.","evidence":"Co-immunoprecipitation, BN-PAGE, and mass spectrometry in yeast","pmids":["17882259"],"confidence":"High","gaps":["Order of factor addition and release from the Cox14-containing intermediate was unclear","Functional significance of transitional supercomplexes was not established"]},{"year":2009,"claim":"Establishing that Cox14 is strictly required for stable Mss51–Cox1 association defined Cox14 as the essential scaffold enabling translational feedback rather than a passive participant.","evidence":"Co-immunoprecipitation of newly synthesized Cox1 and ARG8m reporter assays in cox14Δ yeast","pmids":["19710419"],"confidence":"High","gaps":["Whether Cox14 contacts Mss51 directly or only via Cox1 was not resolved","Structural basis of the interaction was unknown"]},{"year":2010,"claim":"Identification of Coa3 as a co-essential partner of Cox14 in early assembly intermediates, and demonstration that the Cox1 C-terminal domain is required for Mss51 sequestration, refined the feedback model to a multi-component, signal-dependent mechanism.","evidence":"Co-immunoprecipitation, BN-PAGE, mass spectrometry (Coa3 discovery), and Cox1 C-terminal truncation mutagenesis in yeast","pmids":["20876281","20807763","21068384"],"confidence":"High","gaps":["Stoichiometry and architecture of the early assembly complex were unknown","How Mss51 transitions from latent to active state at the molecular level was unresolved"]},{"year":2012,"claim":"Identification of human C12orf62 as the COX14 ortholog, and demonstration that its loss-of-function mutations cause impaired COX1 synthesis and fatal neonatal lactic acidosis, established conservation of the COX14-dependent translational coupling mechanism in mammals.","evidence":"Homozygosity mapping, siRNA knockdown, retroviral rescue, co-immunoprecipitation, 2D BN-PAGE in human fibroblasts and patient cells","pmids":["22243966","22356826"],"confidence":"High","gaps":["Mammalian functional equivalent of Mss51-mediated feedback was not identified","Tissue-specific consequences of COX14 deficiency were unexplored"]},{"year":2015,"claim":"Reciprocal protein stability analysis in patient fibroblasts showed COX14 and COA3 are mutually required for each other's stability, establishing their co-dependent relationship in the human early COX1 assembly complex.","evidence":"Immunoblot and BN-PAGE analysis of COA3- and COX14-deficient patient fibroblasts with retroviral rescue","pmids":["25604084"],"confidence":"High","gaps":["Whether this co-dependence reflects direct physical contact or indirect stabilization was not distinguished","Other stabilizing or chaperoning factors for the human complex were not identified"]},{"year":2016,"claim":"Demonstration that COX14 engages with translating mitoribosomes synthesizing COX1, and that assembly defects stall translation at ribosome–nascent chain complexes, established that COX14 operates co-translationally to couple membrane insertion with assembly.","evidence":"Ribosome nascent chain complex isolation, SILAC-based quantitative mass spectrometry, siRNA knockdown, and pulse-labeling in human cells","pmids":["27693358"],"confidence":"High","gaps":["Mechanism by which COX14 is recruited to the ribosome exit tunnel was unknown","Whether translational arrest is reversible in physiological conditions was not tested"]},{"year":2017,"claim":"Identification of CMC1 as a stabilizer of the COX1–COA3–COX14 complex prior to nuclear-encoded subunit addition, and confirmation that Cox1 C-terminal point mutations disrupt Mss51–Cox14 binding, refined the sequential order and molecular determinants of early assembly.","evidence":"TALEN-mediated CMC1 KO with BN-PAGE and co-IP in human cells; Cox1 C-terminal mutagenesis with co-IP and pulse-labeling in yeast","pmids":["28082314","28490636","28931599"],"confidence":"High","gaps":["Atomic-resolution structure of the early assembly intermediate was still lacking","How nuclear-encoded subunits COX4/COX5a are handed off from the COX14-containing complex was not resolved"]},{"year":2024,"claim":"A COX14 M19I knock-in mouse model revealed that COX14 deficiency triggers mitochondrial ROS-driven release of mtRNA into the cytosol, activating RIG-I–mediated inflammation in a tissue-specific manner, uncovering a previously unknown link between complex IV assembly failure and innate immune activation.","evidence":"COX14 M19I knock-in mouse, mitochondrial pulse-labeling, ROS quantification, cytosolic mtRNA detection, RIG-I pathway assays, comparison with COA3 Y72C model","pmids":["39134548"],"confidence":"High","gaps":["Mechanism of selective mtRNA release from mitochondria is undefined","Whether RIG-I activation contributes to pathology in human patients with COX14 mutations is untested","Basis for tissue-specificity of the inflammatory phenotype is unknown"]},{"year":null,"claim":"No atomic-resolution structure of the COX14-containing early assembly intermediate exists, the mammalian functional equivalent of Mss51-mediated translational feedback has not been molecularly identified, and the mechanism by which COX14 deficiency leads to selective mtRNA release remains unknown.","evidence":"","pmids":[],"confidence":"High","gaps":["Structural basis of COX14 interactions with COX1, COA3, and other partners is unresolved","Identity of the mammalian translational feedback sensor analogous to Mss51 is unknown","Molecular pathway for mtRNA escape from mitochondria upon complex IV deficiency is undefined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[1,3,4,10]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[1,4,5,12]}],"localization":[{"term_id":"GO:0005739","term_label":"mitochondrion","supporting_discovery_ids":[0,7,8]}],"pathway":[{"term_id":"R-HSA-1852241","term_label":"Organelle biogenesis and maintenance","supporting_discovery_ids":[0,7,10,11]},{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[0,7,9]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[14]}],"complexes":["COX1-COX14-COA3-Mss51 early assembly intermediate","COX1-COX14-COA3-CMC1 complex"],"partners":["MT-CO1","COA3","MSS51","CMC1","SURF1","COX25"],"other_free_text":[]},"mechanistic_narrative":"COX14 is a small single-pass inner mitochondrial membrane protein that functions as an essential assembly factor for cytochrome c oxidase (complex IV) by nucleating an early assembly intermediate containing newly synthesized COX1, COA3, and the translational regulator Mss51, thereby coupling COX1 mRNA translation to the progress of COX assembly [PMID:15306853, PMID:20876281, PMID:22243966]. Within this intermediate, COX14 sequesters Mss51 in a translationally inactive state—a process dependent on the COX1 C-terminal domain—creating a negative feedback loop that downregulates COX1 synthesis when assembly is stalled [PMID:19710419, PMID:20807763, PMID:28490636]. COX14 and COA3 are mutually required for protein stability and together scaffold the recruitment of additional factors including CMC1, Shy1/SURF1, and mitoribosomal components to coordinate co-translational membrane insertion with downstream assembly steps [PMID:25604084, PMID:28082314, PMID:27693358]. Loss-of-function mutations in human COX14 (C12orf62) cause fatal neonatal lactic acidosis with complex IV deficiency, and in a mouse model COX14 deficiency triggers ROS-driven release of mitochondrial RNA into the cytosol, activating RIG-I–mediated tissue-specific inflammation [PMID:22243966, PMID:39134548]."},"prefetch_data":{"uniprot":{"accession":"Q96I36","full_name":"Cytochrome c oxidase assembly protein COX14","aliases":[],"length_aa":57,"mass_kda":6.6,"function":"Core component of the MITRAC (mitochondrial translation regulation assembly intermediate of cytochrome c oxidase complex) complex, that regulates cytochrome c oxidase assembly. Requires for coordination of the early steps of cytochrome c oxidase assembly with the synthesis of MT-CO1","subcellular_location":"Mitochondrion outer membrane","url":"https://www.uniprot.org/uniprotkb/Q96I36/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/COX14","classification":"Not Classified","n_dependent_lines":104,"n_total_lines":1208,"dependency_fraction":0.08609271523178808},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/COX14","total_profiled":1310},"omim":[{"mim_id":"619059","title":"MITOCHONDRIAL COMPLEX IV DEFICIENCY, NUCLEAR TYPE 15; MC4DN15","url":"https://www.omim.org/entry/619059"},{"mim_id":"619058","title":"MITOCHONDRIAL COMPLEX IV DEFICIENCY, NUCLEAR TYPE 14; MC4DN14","url":"https://www.omim.org/entry/619058"},{"mim_id":"619053","title":"MITOCHONDRIAL COMPLEX IV DEFICIENCY, NUCLEAR TYPE 10; MC4DN10","url":"https://www.omim.org/entry/619053"},{"mim_id":"614775","title":"CYTOCHROME C OXIDASE ASSEMBLY FACTOR 3; COA3","url":"https://www.omim.org/entry/614775"},{"mim_id":"614774","title":"PENTATRICOPEPTIDE REPEAT DOMAIN-CONTAINING PROTEIN 1; PTCD1","url":"https://www.omim.org/entry/614774"}],"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/COX14"},"hgnc":{"alias_symbol":["MGC14288"],"prev_symbol":["C12orf62"]},"alphafold":{"accession":"Q96I36","domains":[{"cath_id":"1.20.5","chopping":"29-57","consensus_level":"medium","plddt":82.2531,"start":29,"end":57}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q96I36","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q96I36-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q96I36-F1-predicted_aligned_error_v6.png","plddt_mean":85.69},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=COX14","jax_strain_url":"https://www.jax.org/strain/search?query=COX14"},"sequence":{"accession":"Q96I36","fasta_url":"https://rest.uniprot.org/uniprotkb/Q96I36.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q96I36/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q96I36"}},"corpus_meta":[{"pmid":"15306853","id":"PMC_15306853","title":"Mss51p and Cox14p jointly regulate mitochondrial Cox1p expression in Saccharomyces cerevisiae.","date":"2004","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/15306853","citation_count":180,"is_preprint":false},{"pmid":"27693358","id":"PMC_27693358","title":"Mitochondrial Protein Synthesis Adapts to Influx of Nuclear-Encoded Protein.","date":"2016","source":"Cell","url":"https://pubmed.ncbi.nlm.nih.gov/27693358","citation_count":173,"is_preprint":false},{"pmid":"17882259","id":"PMC_17882259","title":"Shy1 couples Cox1 translational regulation to cytochrome c oxidase assembly.","date":"2007","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/17882259","citation_count":113,"is_preprint":false},{"pmid":"20876281","id":"PMC_20876281","title":"Coa3 and Cox14 are essential for negative feedback regulation of COX1 translation in mitochondria.","date":"2010","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/20876281","citation_count":102,"is_preprint":false},{"pmid":"22243966","id":"PMC_22243966","title":"Mutations in C12orf62, a factor that couples COX I synthesis with cytochrome c oxidase assembly, cause fatal neonatal lactic acidosis.","date":"2012","source":"American journal of human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/22243966","citation_count":82,"is_preprint":false},{"pmid":"22356826","id":"PMC_22356826","title":"Iterative orthology prediction uncovers new mitochondrial proteins and identifies C12orf62 as the human ortholog of COX14, a protein involved in the assembly of cytochrome c oxidase.","date":"2012","source":"Genome biology","url":"https://pubmed.ncbi.nlm.nih.gov/22356826","citation_count":80,"is_preprint":false},{"pmid":"19710419","id":"PMC_19710419","title":"Dual functions of Mss51 couple synthesis of Cox1 to assembly of cytochrome c oxidase in Saccharomyces cerevisiae mitochondria.","date":"2009","source":"Molecular biology of the cell","url":"https://pubmed.ncbi.nlm.nih.gov/19710419","citation_count":79,"is_preprint":false},{"pmid":"7797555","id":"PMC_7797555","title":"Cloning and characterization of COX14, whose product is required for assembly of yeast cytochrome oxidase.","date":"1995","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/7797555","citation_count":68,"is_preprint":false},{"pmid":"21068384","id":"PMC_21068384","title":"Cox25 teams up with Mss51, Ssc1, and Cox14 to regulate mitochondrial cytochrome c oxidase subunit 1 expression and assembly in Saccharomyces cerevisiae.","date":"2010","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/21068384","citation_count":68,"is_preprint":false},{"pmid":"28082314","id":"PMC_28082314","title":"A CMC1-knockout reveals translation-independent control of human mitochondrial complex IV biogenesis.","date":"2017","source":"EMBO reports","url":"https://pubmed.ncbi.nlm.nih.gov/28082314","citation_count":64,"is_preprint":false},{"pmid":"25604084","id":"PMC_25604084","title":"Mutations in COA3 cause isolated complex IV deficiency associated with neuropathy, exercise intolerance, obesity, and short stature.","date":"2015","source":"Journal of medical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/25604084","citation_count":51,"is_preprint":false},{"pmid":"17135289","id":"PMC_17135289","title":"Aberrant translation of cytochrome c oxidase subunit 1 mRNA species in the absence of Mss51p in the yeast Saccharomyces cerevisiae.","date":"2006","source":"Molecular biology of the cell","url":"https://pubmed.ncbi.nlm.nih.gov/17135289","citation_count":49,"is_preprint":false},{"pmid":"20807763","id":"PMC_20807763","title":"The carboxyl-terminal end of Cox1 is required for feedback assembly regulation of Cox1 synthesis in Saccharomyces cerevisiae mitochondria.","date":"2010","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/20807763","citation_count":34,"is_preprint":false},{"pmid":"28931599","id":"PMC_28931599","title":"MrpL35, a mitospecific component of mitoribosomes, plays a key role in cytochrome c oxidase assembly.","date":"2017","source":"Molecular biology of the cell","url":"https://pubmed.ncbi.nlm.nih.gov/28931599","citation_count":30,"is_preprint":false},{"pmid":"28490636","id":"PMC_28490636","title":"The Cox1 C-terminal domain is a central regulator of cytochrome c oxidase biogenesis in yeast mitochondria.","date":"2017","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/28490636","citation_count":28,"is_preprint":false},{"pmid":"16339141","id":"PMC_16339141","title":"COX24 codes for a mitochondrial protein required for processing of the COX1 transcript.","date":"2005","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/16339141","citation_count":22,"is_preprint":false},{"pmid":"26929411","id":"PMC_26929411","title":"A Novel Function of Pet54 in Regulation of Cox1 Synthesis in Saccharomyces cerevisiae Mitochondria.","date":"2016","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/26929411","citation_count":17,"is_preprint":false},{"pmid":"39134548","id":"PMC_39134548","title":"Defective mitochondrial COX1 translation due to loss of COX14 function triggers ROS-induced inflammation in mouse liver.","date":"2024","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/39134548","citation_count":15,"is_preprint":false},{"pmid":"19348890","id":"PMC_19348890","title":"Chapter 11 Supercomplex organization of the yeast respiratory chain complexes and the ADP/ATP carrier proteins.","date":"2009","source":"Methods in enzymology","url":"https://pubmed.ncbi.nlm.nih.gov/19348890","citation_count":11,"is_preprint":false},{"pmid":"28357365","id":"PMC_28357365","title":"Cox1 mutation abrogates need for Cox23 in cytochrome c oxidase biogenesis.","date":"2016","source":"Microbial cell (Graz, Austria)","url":"https://pubmed.ncbi.nlm.nih.gov/28357365","citation_count":8,"is_preprint":false},{"pmid":"35779633","id":"PMC_35779633","title":"Overexpression of MRX9 impairs processing of RNAs encoding mitochondrial oxidative phosphorylation factors COB and COX1 in yeast.","date":"2022","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/35779633","citation_count":5,"is_preprint":false},{"pmid":"38928699","id":"PMC_38928699","title":"A Machine Learning Model for the Prediction of COVID-19 Severity Using RNA-Seq, Clinical, and Co-Morbidity Data.","date":"2024","source":"Diagnostics (Basel, Switzerland)","url":"https://pubmed.ncbi.nlm.nih.gov/38928699","citation_count":4,"is_preprint":false},{"pmid":"12366840","id":"PMC_12366840","title":"Suppression of a nuclear frameshift mutation by a mitochondrial tRNA in the yeast Kluyveromyces lactis.","date":"2002","source":"Molecular microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/12366840","citation_count":3,"is_preprint":false},{"pmid":"34515013","id":"PMC_34515013","title":"Inactivation of PDH can Reduce Anaplastic Thyroid Cancer Cells' Sensitivity to Artemisinin.","date":"2022","source":"Anti-cancer agents in medicinal chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/34515013","citation_count":2,"is_preprint":false},{"pmid":"42038475","id":"PMC_42038475","title":"Multi-omics analysis reveals key genes associated with clear cell renal cell carcinoma.","date":"2026","source":"PeerJ","url":"https://pubmed.ncbi.nlm.nih.gov/42038475","citation_count":0,"is_preprint":false},{"pmid":"41683958","id":"PMC_41683958","title":"Multi-Omics Analysis of a Spontaneous Type 2 Diabetes Model in Myodes rufocanus and Its Underlying Mechanisms.","date":"2026","source":"International journal of molecular sciences","url":"https://pubmed.ncbi.nlm.nih.gov/41683958","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":13311,"output_tokens":3821,"usd":0.048624},"stage2":{"model":"claude-opus-4-6","input_tokens":7261,"output_tokens":2927,"usd":0.16422},"total_usd":0.212844,"stage1_batch_id":"msgbatch_011kfMfE81o6CTcyhVUqumuW","stage2_batch_id":"msgbatch_01DTputS6WNkH745x1nVSoBo","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1995,\n      \"finding\": \"COX14 encodes a low molecular mass protein (~8 kDa) that localizes to the mitochondrial membrane and is associated with a high molecular weight complex; loss of COX14 results in a cytochrome oxidase assembly-arrested phenotype despite normal synthesis of mitochondrially encoded COX subunits, establishing COX14 as a COX assembly factor acting at a late stage of the pathway.\",\n      \"method\": \"Complementation cloning, Western analysis, biotinylated gene fusion localization, cytochrome oxidase activity assay\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — original cloning paper with multiple orthogonal methods and functional validation via complementation\",\n      \"pmids\": [\"7797555\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"Cox14p and Mss51p (a COX1 mRNA translational activator) interact with each other and with newly synthesized Cox1p to form a transient Cox14p–Cox1p–Mss51p assembly intermediate complex; this complex functions to downregulate Cox1p synthesis (sequestering Mss51p), and deletion of COX14 alone does not reduce Cox1p synthesis because the sequestration complex fails to form.\",\n      \"method\": \"Co-immunoprecipitation, pulse-labeling of mitochondrial translation products, genetic epistasis (cox14 null combined with other COX mutants and mss51 suppressor mutations)\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal Co-IP plus genetic epistasis, replicated by multiple subsequent labs\",\n      \"pmids\": [\"15306853\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Shy1 (yeast SURF1 ortholog) interacts with Mss51 and Cox14 in translational regulatory complexes and also associates with later COX assembly subcomplexes; Cox14-containing partially assembled COX complexes can associate with the bc1 complex to form transitional supercomplexes, linking Cox1 translational regulation to supercomplex formation.\",\n      \"method\": \"Co-immunoprecipitation, native gel electrophoresis (BN-PAGE), affinity purification, mass spectrometry\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods (Co-IP, BN-PAGE, MS) in a single study with strong mechanistic follow-up\",\n      \"pmids\": [\"17882259\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"Mss51 does not stably interact with newly synthesized Cox1 in a cox14 null mutant, demonstrating that Cox14 is required for sequestration of Mss51 in early COX assembly intermediates; the Mss51–Cox14 physical interaction depends on the presence of newly synthesized Cox1, indicating dynamic assembly of Cox1-nucleated early intermediates.\",\n      \"method\": \"Co-immunoprecipitation of newly synthesized Cox1, pulse-labeling, ARG8m reporter assay for translational output\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods, mechanistically rigorous, consistent with prior and subsequent work\",\n      \"pmids\": [\"19710419\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Coa3 and Cox14 together form early COX assembly intermediates with newly synthesized Cox1 and are both required for Mss51 association with these complexes; Mss51 exists in equilibrium between a latent (translational resting) state and a committed (translation-effective) state represented as distinct complexes, and Coa3/Cox14 promote formation of the latent state to downregulate COX1 expression; Coa1 binding to Mss51 in complex with Cox14, Coa3, and Cox1 is essential for full Mss51 inactivation.\",\n      \"method\": \"Co-immunoprecipitation, pulse-labeling, BN-PAGE, identification of novel assembly factor Coa3 (Yjl062w-A) by mass spectrometry\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal biochemical methods, novel factor identification, consistent with prior epistasis data\",\n      \"pmids\": [\"20876281\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Deletion of the C-terminal 11 or 15 residues of Cox1 eliminates assembly-feedback control of Cox1 synthesis and reduces the strength of the Mss51–Cox14 interaction, establishing that the Cox1 C-terminal domain is required for Mss51 sequestration via Cox14 in early assembly intermediates.\",\n      \"method\": \"Site-directed mutagenesis of mtDNA, co-immunoprecipitation, pulse-labeling, ARG8m reporter assay\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1/2 — mutagenesis combined with Co-IP and translational reporter, mechanistically informative\",\n      \"pmids\": [\"20807763\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Cox25 is an inner mitochondrial membrane protein that is an essential component of the Cox1–Ssc1–Mss51–Cox14 early assembly complex; after Ssc1–Mss51 release, Cox25 continues to interact with Cox14 and Cox1 to facilitate formation of multisubunit COX assembly intermediates and also interacts with Shy1 and Cox5 in a separate Mss51-free complex.\",\n      \"method\": \"Co-immunoprecipitation, BN-PAGE, pulse-labeling, genetic epistasis (cox25 null phenotype)\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods, novel interactor identified, mechanistic follow-up provided\",\n      \"pmids\": [\"21068384\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"C12orf62 (human ortholog of yeast COX14, also called COX14 in humans) is a small (~6 kDa) single-transmembrane protein that localizes to mitochondria, co-immunoprecipitates with COX I, COX II, and COX IV, and is required for coupling early COX assembly steps with COX I synthesis; loss-of-function mutations cause COX-assembly defects with specific decrease in COX I synthesis and fatal neonatal lactic acidosis.\",\n      \"method\": \"Microcell-mediated chromosome transfer, homozygosity mapping, siRNA knockdown, retroviral rescue, co-immunoprecipitation with epitope-tagged C12orf62, 2D BN-PAGE of newly synthesized subunits, immunoblot\",\n      \"journal\": \"American journal of human genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods including patient mutations, rescue, Co-IP, and metabolic labeling\",\n      \"pmids\": [\"22243966\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Iterative orthology prediction (Ortho-Profile) confirmed that human C12orf62 is the functional ortholog of yeast COX14; experimental validation of subcellular localization to mitochondria and co-purification with human COX-associated proteins confirmed its role in negative regulation of COX I translation.\",\n      \"method\": \"Bioinformatic orthology prediction validated by experimental co-purification and localization studies\",\n      \"journal\": \"Genome biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 — orthology confirmed by co-purification and localization, functional validation derived from companion paper\",\n      \"pmids\": [\"22356826\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"COX14 (C12orf62) and COA3 are mutually interdependent for their stability: COX14 protein is undetectable in COA3-deficient patient fibroblasts and COA3 is undetectable in COX14-deficient fibroblasts, demonstrating that they form a co-dependent early COX assembly complex containing COX1.\",\n      \"method\": \"Immunoblot analysis of patient fibroblasts with COA3 or COX14 mutations, BN-PAGE, pulse-labeling, retroviral rescue\",\n      \"journal\": \"Journal of medical genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal protein stability analysis in human patient cells with rescue experiments\",\n      \"pmids\": [\"25604084\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"Human mitochondrial ribosomes translating COX1 mRNA selectively engage with cytochrome c oxidase assembly factors (including COX14) in the inner membrane; COX assembly defects arrest mitochondrial translation in a ribosome–nascent chain complex with partially membrane-inserted COX1, establishing a translational plasticity pathway in which COX14 participates in coupling synthesis to assembly.\",\n      \"method\": \"Ribosome nascent chain complex isolation, BN-PAGE, quantitative mass spectrometry (SILAC), siRNA knockdown, pulse-labeling\",\n      \"journal\": \"Cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — rigorous biochemical isolation of ribosome-nascent chain complexes with quantitative MS, multiple orthogonal methods\",\n      \"pmids\": [\"27693358\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"CMC1 forms an early COX assembly intermediate with COX1, COA3, and COX14; CMC1 knockout shows normal COX1 synthesis but decreased COX activity due to instability of newly synthesized COX1, and CMC1 stabilizes the COX1–COA3–COX14 complex prior to incorporation of COX4 and COX5a; CMC1 acts independently of COX10, COX11, SURF1 (metallation/late stability factors), indicating a distinct role for the COX14-containing early complex.\",\n      \"method\": \"TALEN-mediated knockout, BN-PAGE, co-immunoprecipitation, pulse-labeling, immunoblot\",\n      \"journal\": \"EMBO reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — genetic KO with multiple biochemical readouts and epistatic dissection of assembly pathway\",\n      \"pmids\": [\"28082314\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Cox1 C-terminal mutations (P521A/P522A and V524E) disrupt the regulatory role of the Cox1 C-terminus by reducing binding of Mss51 and Cox14 to COA complexes, enriching Mss51 in a translationally active form and maintaining full Cox1 synthesis even when COX assembly is blocked; this confirms that the Cox1 C-terminal domain directly mediates the Mss51–Cox14 interaction within assembly intermediates.\",\n      \"method\": \"Site-directed mutagenesis of mitochondrial COX1 gene, co-immunoprecipitation, BN-PAGE, pulse-labeling\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1/2 — mutagenesis with Co-IP and translational assays, mechanistically rigorous\",\n      \"pmids\": [\"28490636\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Mitospecific ribosomal protein MrpL35, together with Mrp7, coordinates Cox1 synthesis with COX assembly in a manner requiring Cox14 and Coa3, indicating that the mitoribosome communicates with the Cox14/Coa3 early assembly module.\",\n      \"method\": \"Genetic analysis of mrpL35 mutants, co-immunoprecipitation, pulse-labeling, epistasis with cox14 deletion\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — genetic and biochemical evidence but cox14 involvement is epistatic inference, not direct interaction demonstrated\",\n      \"pmids\": [\"28931599\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"A COX14 M19I missense mouse model corresponding to a human complex IV deficiency patient shows that COX14 is required for COX1 translation in vivo; loss of COX14 function triggers release of mitochondrial RNA into the cytosol (sensed by the RIG-1 pathway), driven by increased reactive oxygen species from complex IV deficiency, leading to tissue-specific liver inflammation.\",\n      \"method\": \"COX14 M19I knock-in mouse model, pulse-labeling of mitochondrial translation, ROS measurements, cytosolic mtRNA detection, RIG-1 pathway activation assays, comparison with COA3 Y72C mouse model\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — in vivo mouse model with multiple orthogonal functional readouts; companion COA3 model provides epistatic validation\",\n      \"pmids\": [\"39134548\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"COX14 (yeast) / C12orf62 (human COX14) encodes a small (~6–8 kDa) single-pass inner mitochondrial membrane protein that forms an early cytochrome c oxidase (COX/complex IV) assembly intermediate together with newly synthesized COX1, COA3, CMC1, and the translational activator/chaperone Mss51; within this complex, COX14 sequesters Mss51 in a latent, translation-incompetent state (dependent on the Cox1 C-terminal domain), thereby creating a negative feedback loop that couples COX1 mRNA translation to the availability and progress of COX assembly—when assembly is blocked, Mss51 remains trapped in the COX14-containing intermediate and COX1 synthesis is reduced, whereas deletion of COX14 releases Mss51 and de-represses Cox1 synthesis; in humans, loss of COX14 function impairs COX1 translation, destabilizes the COX assembly process, and triggers ROS-driven release of mitochondrial RNA into the cytosol, activating RIG-1–mediated inflammation in a tissue-specific manner.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"COX14 is a small single-pass inner mitochondrial membrane protein that functions as an essential assembly factor for cytochrome c oxidase (complex IV) by nucleating an early assembly intermediate containing newly synthesized COX1, COA3, and the translational regulator Mss51, thereby coupling COX1 mRNA translation to the progress of COX assembly [PMID:15306853, PMID:20876281, PMID:22243966]. Within this intermediate, COX14 sequesters Mss51 in a translationally inactive state—a process dependent on the COX1 C-terminal domain—creating a negative feedback loop that downregulates COX1 synthesis when assembly is stalled [PMID:19710419, PMID:20807763, PMID:28490636]. COX14 and COA3 are mutually required for protein stability and together scaffold the recruitment of additional factors including CMC1, Shy1/SURF1, and mitoribosomal components to coordinate co-translational membrane insertion with downstream assembly steps [PMID:25604084, PMID:28082314, PMID:27693358]. Loss-of-function mutations in human COX14 (C12orf62) cause fatal neonatal lactic acidosis with complex IV deficiency, and in a mouse model COX14 deficiency triggers ROS-driven release of mitochondrial RNA into the cytosol, activating RIG-I–mediated tissue-specific inflammation [PMID:22243966, PMID:39134548].\",\n  \"teleology\": [\n    {\n      \"year\": 1995,\n      \"claim\": \"Identification of COX14 as a mitochondrial membrane-associated COX assembly factor established that a small protein is required for cytochrome oxidase biogenesis despite normal mitochondrial translation of COX subunits.\",\n      \"evidence\": \"Complementation cloning, Western blot, and cytochrome oxidase activity assays in yeast\",\n      \"pmids\": [\"7797555\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Mechanism by which COX14 promotes assembly was unknown\",\n        \"Position in the assembly pathway (early vs. late) was not resolved\",\n        \"No interacting partners identified\"\n      ]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Discovery that Cox14 forms a transient complex with newly synthesized Cox1 and the translational activator Mss51 revealed a feedback mechanism in which Cox14 sequesters Mss51 to downregulate Cox1 synthesis when assembly stalls.\",\n      \"evidence\": \"Reciprocal co-immunoprecipitation, pulse-labeling, and genetic epistasis in yeast\",\n      \"pmids\": [\"15306853\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Whether additional factors participate in the early assembly intermediate was unknown\",\n        \"The molecular determinant on Cox1 mediating the interaction was unidentified\",\n        \"Whether this feedback loop is conserved in mammals was untested\"\n      ]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Demonstration that Shy1 (SURF1 ortholog) associates with Cox14-containing complexes and that these partially assembled intermediates form transitional supercomplexes with complex III linked COX14-mediated early assembly to later stages of respiratory chain organization.\",\n      \"evidence\": \"Co-immunoprecipitation, BN-PAGE, and mass spectrometry in yeast\",\n      \"pmids\": [\"17882259\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Order of factor addition and release from the Cox14-containing intermediate was unclear\",\n        \"Functional significance of transitional supercomplexes was not established\"\n      ]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Establishing that Cox14 is strictly required for stable Mss51–Cox1 association defined Cox14 as the essential scaffold enabling translational feedback rather than a passive participant.\",\n      \"evidence\": \"Co-immunoprecipitation of newly synthesized Cox1 and ARG8m reporter assays in cox14Δ yeast\",\n      \"pmids\": [\"19710419\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Whether Cox14 contacts Mss51 directly or only via Cox1 was not resolved\",\n        \"Structural basis of the interaction was unknown\"\n      ]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Identification of Coa3 as a co-essential partner of Cox14 in early assembly intermediates, and demonstration that the Cox1 C-terminal domain is required for Mss51 sequestration, refined the feedback model to a multi-component, signal-dependent mechanism.\",\n      \"evidence\": \"Co-immunoprecipitation, BN-PAGE, mass spectrometry (Coa3 discovery), and Cox1 C-terminal truncation mutagenesis in yeast\",\n      \"pmids\": [\"20876281\", \"20807763\", \"21068384\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Stoichiometry and architecture of the early assembly complex were unknown\",\n        \"How Mss51 transitions from latent to active state at the molecular level was unresolved\"\n      ]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Identification of human C12orf62 as the COX14 ortholog, and demonstration that its loss-of-function mutations cause impaired COX1 synthesis and fatal neonatal lactic acidosis, established conservation of the COX14-dependent translational coupling mechanism in mammals.\",\n      \"evidence\": \"Homozygosity mapping, siRNA knockdown, retroviral rescue, co-immunoprecipitation, 2D BN-PAGE in human fibroblasts and patient cells\",\n      \"pmids\": [\"22243966\", \"22356826\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Mammalian functional equivalent of Mss51-mediated feedback was not identified\",\n        \"Tissue-specific consequences of COX14 deficiency were unexplored\"\n      ]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Reciprocal protein stability analysis in patient fibroblasts showed COX14 and COA3 are mutually required for each other's stability, establishing their co-dependent relationship in the human early COX1 assembly complex.\",\n      \"evidence\": \"Immunoblot and BN-PAGE analysis of COA3- and COX14-deficient patient fibroblasts with retroviral rescue\",\n      \"pmids\": [\"25604084\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Whether this co-dependence reflects direct physical contact or indirect stabilization was not distinguished\",\n        \"Other stabilizing or chaperoning factors for the human complex were not identified\"\n      ]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Demonstration that COX14 engages with translating mitoribosomes synthesizing COX1, and that assembly defects stall translation at ribosome–nascent chain complexes, established that COX14 operates co-translationally to couple membrane insertion with assembly.\",\n      \"evidence\": \"Ribosome nascent chain complex isolation, SILAC-based quantitative mass spectrometry, siRNA knockdown, and pulse-labeling in human cells\",\n      \"pmids\": [\"27693358\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Mechanism by which COX14 is recruited to the ribosome exit tunnel was unknown\",\n        \"Whether translational arrest is reversible in physiological conditions was not tested\"\n      ]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Identification of CMC1 as a stabilizer of the COX1–COA3–COX14 complex prior to nuclear-encoded subunit addition, and confirmation that Cox1 C-terminal point mutations disrupt Mss51–Cox14 binding, refined the sequential order and molecular determinants of early assembly.\",\n      \"evidence\": \"TALEN-mediated CMC1 KO with BN-PAGE and co-IP in human cells; Cox1 C-terminal mutagenesis with co-IP and pulse-labeling in yeast\",\n      \"pmids\": [\"28082314\", \"28490636\", \"28931599\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Atomic-resolution structure of the early assembly intermediate was still lacking\",\n        \"How nuclear-encoded subunits COX4/COX5a are handed off from the COX14-containing complex was not resolved\"\n      ]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"A COX14 M19I knock-in mouse model revealed that COX14 deficiency triggers mitochondrial ROS-driven release of mtRNA into the cytosol, activating RIG-I–mediated inflammation in a tissue-specific manner, uncovering a previously unknown link between complex IV assembly failure and innate immune activation.\",\n      \"evidence\": \"COX14 M19I knock-in mouse, mitochondrial pulse-labeling, ROS quantification, cytosolic mtRNA detection, RIG-I pathway assays, comparison with COA3 Y72C model\",\n      \"pmids\": [\"39134548\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Mechanism of selective mtRNA release from mitochondria is undefined\",\n        \"Whether RIG-I activation contributes to pathology in human patients with COX14 mutations is untested\",\n        \"Basis for tissue-specificity of the inflammatory phenotype is unknown\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"No atomic-resolution structure of the COX14-containing early assembly intermediate exists, the mammalian functional equivalent of Mss51-mediated translational feedback has not been molecularly identified, and the mechanism by which COX14 deficiency leads to selective mtRNA release remains unknown.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Structural basis of COX14 interactions with COX1, COA3, and other partners is unresolved\",\n        \"Identity of the mammalian translational feedback sensor analogous to Mss51 is unknown\",\n        \"Molecular pathway for mtRNA escape from mitochondria upon complex IV deficiency is undefined\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\n        \"term_id\": \"GO:0060090\",\n        \"supporting_discovery_ids\": [1, 3, 4, 10]\n      },\n      {\n        \"term_id\": \"GO:0098772\",\n        \"supporting_discovery_ids\": [1, 4, 5, 12]\n      }\n    ],\n    \"localization\": [\n      {\n        \"term_id\": \"GO:0005739\",\n        \"supporting_discovery_ids\": [0, 7, 8]\n      }\n    ],\n    \"pathway\": [\n      {\n        \"term_id\": \"R-HSA-1852241\",\n        \"supporting_discovery_ids\": [0, 7, 10, 11]\n      },\n      {\n        \"term_id\": \"R-HSA-1430728\",\n        \"supporting_discovery_ids\": [0, 7, 9]\n      },\n      {\n        \"term_id\": \"R-HSA-168256\",\n        \"supporting_discovery_ids\": [14]\n      }\n    ],\n    \"complexes\": [\n      \"COX1-COX14-COA3-Mss51 early assembly intermediate\",\n      \"COX1-COX14-COA3-CMC1 complex\"\n    ],\n    \"partners\": [\n      \"MT-CO1\",\n      \"COA3\",\n      \"MSS51\",\n      \"CMC1\",\n      \"SURF1\",\n      \"COX25\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}