{"gene":"TARS2","run_date":"2026-06-10T10:51:54","timeline":{"discoveries":[{"year":2014,"finding":"TARS2 encodes a mitochondrial threonyl-tRNA synthetase; pathogenic mutations reduce TARS2 protein levels and mitochondrial threonyl-tRNA levels, impairing mitochondrial respiration. Expression of wild-type TARS2 transcript in mutant fibroblasts rescued the biochemical impairment of mitochondrial respiration.","method":"Whole-exome sequencing, protein quantification, tRNA level measurement, functional rescue by wild-type transcript expression in immortalized patient fibroblasts","journal":"Human mutation","confidence":"High","confidence_rationale":"Tier 2 / Strong — direct rescue experiment in patient cells with measurement of protein, tRNA, and respiratory chain function; replicated across two affected siblings","pmids":["24827421"],"is_preprint":false},{"year":2020,"finding":"TARS2 interacts with inactive Rag GTPases, particularly GTP-loaded RagC, and this interaction leads to increased GTP loading of RagA, thereby activating mTORC1 in response to threonine availability. Cells lacking TARS2 are resistant to threonine-dependent mTORC1 activation, whereas cytoplasmic threonyl-tRNA synthetase TARS is not required for this effect.","method":"Co-immunoprecipitation of TARS2 with Rag GTPases, GTP-loading assays of RagA, TARS2 knockout cell lines, mTORC1 activity assays under threonine repletion/depletion conditions","journal":"Molecular cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP with Rag GTPases, GTP-loading biochemical assay, genetic KO with defined mTORC1 activity readout, specificity confirmed by TARS negative result","pmids":["33340489"],"is_preprint":false},{"year":2022,"finding":"TARS2 is responsible for generating mitochondrial Thr-tRNAThr and for clearing mischarged Ser-tRNAThr during mitochondrial translation. Pathogenic missense variants in TARS2 reduce TARS2 protein stability and/or aminoacylation function, as demonstrated by homology modeling and functional studies.","method":"Functional studies assessing TARS2 aminoacylation activity, protein stability assays, homology modeling of pathogenic variants","journal":"Human molecular genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional aminoacylation and stability assays in a single lab with homology modeling; editing/deacylation activity inferred from abstract without full reconstitution detail","pmids":["34508595"],"is_preprint":false},{"year":2023,"finding":"Pathogenic TARS2 variants within the TARS2 301-381 region impair binding to Rag GTPases, thereby disrupting mTORC1 activation. A zebrafish tars2 model recapitulated key features of the human phenotype and showed dysregulation of downstream mTORC1 signaling targets.","method":"In vitro binding assays of TARS2 variants to Rag GTPases, zebrafish tars2 loss-of-function model with mTORC1 downstream target analysis","journal":"Genetics in medicine : official journal of the American College of Medical Genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vitro binding assay mapping a functional domain, zebrafish model with pathway readout; single lab, two orthogonal methods","pmids":["37454282"],"is_preprint":false},{"year":2026,"finding":"TARS2 overexpression in cardiomyocytes disrupts mitochondrial homeostasis and triggers excessive mitochondrial reactive oxygen species (ROS) production leading to cardiomyocyte apoptosis, while genetic inhibition of TARS2 restores mitochondrial function, reduces apoptosis, and improves cardiac performance.","method":"TARS2 overexpression and genetic inhibition in cardiomyocytes, mitochondrial ROS measurement, apoptosis assays, cardiac function assessment","journal":"JACC. Basic to translational science","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — gain- and loss-of-function experiments with defined mitochondrial and apoptotic readouts, but single lab and abstract provides limited methodological detail","pmids":["42048853"],"is_preprint":false}],"current_model":"TARS2 is a mitochondrial threonyl-tRNA synthetase that charges tRNAThr and edits mischarged Ser-tRNAThr for mitochondrial translation; beyond its canonical tRNA synthetase role, it acts as a nutrient sensor by interacting with inactive Rag GTPases (particularly GTP-RagC) to promote RagA GTP-loading and thereby activate mTORC1 in response to threonine availability, with pathogenic loss-of-function variants causing combined oxidative phosphorylation deficiency by impairing both mitochondrial translation and mTORC1 signaling."},"narrative":{"mechanistic_narrative":"TARS2 is a mitochondrial threonyl-tRNA synthetase that supports mitochondrial translation and, separately, acts as a threonine sensor coupling nutrient availability to mTORC1 signaling [PMID:24827421, PMID:33340489]. In its canonical role, TARS2 charges mitochondrial tRNAThr and clears mischarged Ser-tRNAThr, and pathogenic mutations that reduce TARS2 protein levels and aminoacylation function lower mitochondrial threonyl-tRNA and impair mitochondrial respiration, a defect rescued by re-expression of wild-type TARS2 in patient fibroblasts [PMID:24827421, PMID:34508595]. Beyond aminoacylation, TARS2 interacts with inactive Rag GTPases—particularly GTP-loaded RagC—to promote GTP-loading of RagA and thereby activate mTORC1 in response to threonine, an effect specific to TARS2 and not shared by the cytoplasmic enzyme TARS [PMID:33340489]. This signaling function maps to the TARS2 301–381 region, where pathogenic variants disrupt Rag binding and mTORC1 activation, with a zebrafish tars2 model recapitulating the human phenotype and downstream mTORC1 dysregulation [PMID:37454282]. Excess TARS2 in cardiomyocytes perturbs mitochondrial homeostasis and drives ROS-dependent apoptosis, whereas its inhibition restores mitochondrial function and cardiac performance [PMID:42048853].","teleology":[{"year":2014,"claim":"Established that TARS2 is required for mitochondrial respiration via its role in mitochondrial threonyl-tRNA charging, linking loss-of-function variants to a respiratory chain defect.","evidence":"Whole-exome sequencing, protein and tRNA quantification, and rescue by wild-type transcript in patient fibroblasts","pmids":["24827421"],"confidence":"High","gaps":["Did not resolve the editing/deacylation activity of the enzyme","Did not address any extra-translational function"]},{"year":2020,"claim":"Revealed a moonlighting function distinct from aminoacylation: TARS2 senses threonine and activates mTORC1 through Rag GTPase engagement, separating this role from the cytoplasmic synthetase.","evidence":"Reciprocal Co-IP with Rag GTPases, RagA GTP-loading assays, and TARS2 knockout cells with mTORC1 readouts; TARS negative control","pmids":["33340489"],"confidence":"High","gaps":["Structural basis of the TARS2–RagC interaction not defined","Whether aminoacylation and Rag-binding functions are mutually exclusive not resolved"]},{"year":2022,"claim":"Defined the dual catalytic role of TARS2 in generating Thr-tRNAThr and clearing mischarged Ser-tRNAThr, and showed pathogenic variants act by destabilizing the protein or impairing aminoacylation.","evidence":"Aminoacylation and protein stability assays with homology modeling of pathogenic variants","pmids":["34508595"],"confidence":"Medium","gaps":["Editing activity inferred without full reconstitution","Single-lab functional characterization"]},{"year":2023,"claim":"Mapped the Rag-binding determinant to residues 301–381 and demonstrated in vivo that disrupting this interaction dysregulates mTORC1 signaling.","evidence":"In vitro Rag-binding assays of TARS2 variants and a zebrafish tars2 loss-of-function model with mTORC1 target analysis","pmids":["37454282"],"confidence":"Medium","gaps":["Domain mapping from a single lab","Relative contribution of translation vs mTORC1 defects to phenotype not dissected"]},{"year":2026,"claim":"Linked TARS2 dosage to mitochondrial ROS and cardiomyocyte apoptosis, indicating that excess TARS2 is pathogenic in cardiac tissue.","evidence":"Gain- and loss-of-function in cardiomyocytes with mitochondrial ROS, apoptosis, and cardiac function readouts","pmids":["42048853"],"confidence":"Medium","gaps":["Mechanism connecting TARS2 overexpression to ROS not defined","Single-lab study with limited methodological detail"]},{"year":null,"claim":"How the aminoacylation and mTORC1-signaling functions of TARS2 are mechanistically coordinated, and the structural basis of Rag GTPase engagement, remain unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model of the TARS2–Rag complex","Whether threonine binding to the catalytic site gates Rag interaction unknown"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140098","term_label":"catalytic activity, acting on RNA","supporting_discovery_ids":[0,2]},{"term_id":"GO:0016740","term_label":"transferase activity","supporting_discovery_ids":[0,2]},{"term_id":"GO:0003723","term_label":"RNA binding","supporting_discovery_ids":[0,2]},{"term_id":"GO:0140299","term_label":"molecular sensor activity","supporting_discovery_ids":[1,3]}],"localization":[{"term_id":"GO:0005739","term_label":"mitochondrion","supporting_discovery_ids":[0,4]}],"pathway":[{"term_id":"R-HSA-392499","term_label":"Metabolism of proteins","supporting_discovery_ids":[0,2]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[1,3]}],"complexes":[],"partners":["RAGC","RAGA"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9BW92","full_name":"Threonine--tRNA ligase, mitochondrial","aliases":["Threonyl-tRNA synthetase","ThrRS","Threonyl-tRNA synthetase-like 1"],"length_aa":718,"mass_kda":81.0,"function":"Catalyzes the attachment of threonine to tRNA(Thr) in a two-step reaction: threonine is first activated by ATP to form Thr-AMP and then transferred to the acceptor end of tRNA(Thr). Also edits incorrectly charged tRNA(Thr) via its editing domain","subcellular_location":"Mitochondrion matrix","url":"https://www.uniprot.org/uniprotkb/Q9BW92/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":true,"resolved_as":"","url":"https://depmap.org/portal/gene/TARS2","classification":"Common Essential","n_dependent_lines":911,"n_total_lines":1208,"dependency_fraction":0.7541390728476821},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/TARS2","total_profiled":1310},"omim":[{"mim_id":"615918","title":"COMBINED OXIDATIVE PHOSPHORYLATION DEFICIENCY 21; COXPD21","url":"https://www.omim.org/entry/615918"},{"mim_id":"615917","title":"COMBINED OXIDATIVE PHOSPHORYLATION DEFICIENCY 20; COXPD20","url":"https://www.omim.org/entry/615917"},{"mim_id":"612805","title":"THREONYL-tRNA SYNTHETASE 2; TARS2","url":"https://www.omim.org/entry/612805"},{"mim_id":"612802","title":"VALYL-tRNA SYNTHETASE 2; VARS2","url":"https://www.omim.org/entry/612802"},{"mim_id":"609060","title":"COMBINED OXIDATIVE PHOSPHORYLATION DEFICIENCY 1; COXPD1","url":"https://www.omim.org/entry/609060"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Uncertain","locations":[{"location":"Nucleoplasm","reliability":"Uncertain"},{"location":"Cytosol","reliability":"Uncertain"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/TARS2"},"hgnc":{"alias_symbol":["FLJ12528"],"prev_symbol":["TARSL1"]},"alphafold":{"accession":"Q9BW92","domains":[{"cath_id":"3.30.980.10","chopping":"128-292","consensus_level":"medium","plddt":93.5915,"start":128,"end":292},{"cath_id":"3.30.930.10","chopping":"323-379_400-604","consensus_level":"medium","plddt":94.0561,"start":323,"end":604},{"cath_id":"3.40.50.800","chopping":"610-717","consensus_level":"high","plddt":96.6682,"start":610,"end":717}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9BW92","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9BW92-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9BW92-F1-predicted_aligned_error_v6.png","plddt_mean":91.06},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=TARS2","jax_strain_url":"https://www.jax.org/strain/search?query=TARS2"},"sequence":{"accession":"Q9BW92","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9BW92.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9BW92/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9BW92"}},"corpus_meta":[{"pmid":"24827421","id":"PMC_24827421","title":"VARS2 and TARS2 mutations in patients with mitochondrial encephalomyopathies.","date":"2014","source":"Human mutation","url":"https://pubmed.ncbi.nlm.nih.gov/24827421","citation_count":90,"is_preprint":false},{"pmid":"33340489","id":"PMC_33340489","title":"Mitochondrial Threonyl-tRNA Synthetase TARS2 Is Required for Threonine-Sensitive mTORC1 Activation.","date":"2020","source":"Molecular cell","url":"https://pubmed.ncbi.nlm.nih.gov/33340489","citation_count":46,"is_preprint":false},{"pmid":"34508595","id":"PMC_34508595","title":"Elucidating the molecular mechanisms associated with TARS2-related mitochondrial disease.","date":"2022","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/34508595","citation_count":19,"is_preprint":false},{"pmid":"37454282","id":"PMC_37454282","title":"Clinical, neuroradiological, and molecular characterization of mitochondrial threonyl-tRNA-synthetase (TARS2)-related disorder.","date":"2023","source":"Genetics in medicine : official journal of the American College of Medical Genetics","url":"https://pubmed.ncbi.nlm.nih.gov/37454282","citation_count":11,"is_preprint":false},{"pmid":"33153448","id":"PMC_33153448","title":"Novel compound heterozygous TARS2 variants in a Chinese family with mitochondrial encephalomyopathy: a case report.","date":"2020","source":"BMC medical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/33153448","citation_count":9,"is_preprint":false},{"pmid":"39509107","id":"PMC_39509107","title":"A homozygous TARS2 variant is a novel cause of syndromic neonatal diabetes.","date":"2024","source":"Diabetic medicine : a journal of the British Diabetic Association","url":"https://pubmed.ncbi.nlm.nih.gov/39509107","citation_count":6,"is_preprint":false},{"pmid":"36218002","id":"PMC_36218002","title":"Novel TARS2 variant identified in a Chinese patient with mitochondrial encephalomyopathy and a systematic review.","date":"2022","source":"American journal of medical genetics. Part A","url":"https://pubmed.ncbi.nlm.nih.gov/36218002","citation_count":5,"is_preprint":false},{"pmid":"36150709","id":"PMC_36150709","title":"TARS2 Variants Cause Combination Oxidative Phosphorylation Deficiency-21: A Case Report and Literature Review.","date":"2022","source":"Neuropediatrics","url":"https://pubmed.ncbi.nlm.nih.gov/36150709","citation_count":4,"is_preprint":false},{"pmid":"39394138","id":"PMC_39394138","title":"TARS2 c.470 C > G is a chinese-specific founder mutation in three unrelated families with mitochondrial encephalomyopathy.","date":"2024","source":"Orphanet journal of rare diseases","url":"https://pubmed.ncbi.nlm.nih.gov/39394138","citation_count":0,"is_preprint":false},{"pmid":"42048853","id":"PMC_42048853","title":"Systems Biology Identifies TARS2 as a Cardiomyocyte Regulator of Mitochondrial Oxidative Stress in Dilated Cardiomyopathy.","date":"2026","source":"JACC. Basic to translational science","url":"https://pubmed.ncbi.nlm.nih.gov/42048853","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":6727,"output_tokens":1410,"usd":0.020665,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":8098,"output_tokens":2134,"usd":0.04692,"stage2_stop_reason":"end_turn"},"total_usd":0.067585,"stage1_batch_id":"msgbatch_017qqVz33Ga63SCDwzb35XPb","stage2_batch_id":"msgbatch_01Scr2Ei9x4HJMiRGxwrmvLK","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2014,\n      \"finding\": \"TARS2 encodes a mitochondrial threonyl-tRNA synthetase; pathogenic mutations reduce TARS2 protein levels and mitochondrial threonyl-tRNA levels, impairing mitochondrial respiration. Expression of wild-type TARS2 transcript in mutant fibroblasts rescued the biochemical impairment of mitochondrial respiration.\",\n      \"method\": \"Whole-exome sequencing, protein quantification, tRNA level measurement, functional rescue by wild-type transcript expression in immortalized patient fibroblasts\",\n      \"journal\": \"Human mutation\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — direct rescue experiment in patient cells with measurement of protein, tRNA, and respiratory chain function; replicated across two affected siblings\",\n      \"pmids\": [\"24827421\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"TARS2 interacts with inactive Rag GTPases, particularly GTP-loaded RagC, and this interaction leads to increased GTP loading of RagA, thereby activating mTORC1 in response to threonine availability. Cells lacking TARS2 are resistant to threonine-dependent mTORC1 activation, whereas cytoplasmic threonyl-tRNA synthetase TARS is not required for this effect.\",\n      \"method\": \"Co-immunoprecipitation of TARS2 with Rag GTPases, GTP-loading assays of RagA, TARS2 knockout cell lines, mTORC1 activity assays under threonine repletion/depletion conditions\",\n      \"journal\": \"Molecular cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP with Rag GTPases, GTP-loading biochemical assay, genetic KO with defined mTORC1 activity readout, specificity confirmed by TARS negative result\",\n      \"pmids\": [\"33340489\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"TARS2 is responsible for generating mitochondrial Thr-tRNAThr and for clearing mischarged Ser-tRNAThr during mitochondrial translation. Pathogenic missense variants in TARS2 reduce TARS2 protein stability and/or aminoacylation function, as demonstrated by homology modeling and functional studies.\",\n      \"method\": \"Functional studies assessing TARS2 aminoacylation activity, protein stability assays, homology modeling of pathogenic variants\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional aminoacylation and stability assays in a single lab with homology modeling; editing/deacylation activity inferred from abstract without full reconstitution detail\",\n      \"pmids\": [\"34508595\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Pathogenic TARS2 variants within the TARS2 301-381 region impair binding to Rag GTPases, thereby disrupting mTORC1 activation. A zebrafish tars2 model recapitulated key features of the human phenotype and showed dysregulation of downstream mTORC1 signaling targets.\",\n      \"method\": \"In vitro binding assays of TARS2 variants to Rag GTPases, zebrafish tars2 loss-of-function model with mTORC1 downstream target analysis\",\n      \"journal\": \"Genetics in medicine : official journal of the American College of Medical Genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro binding assay mapping a functional domain, zebrafish model with pathway readout; single lab, two orthogonal methods\",\n      \"pmids\": [\"37454282\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"TARS2 overexpression in cardiomyocytes disrupts mitochondrial homeostasis and triggers excessive mitochondrial reactive oxygen species (ROS) production leading to cardiomyocyte apoptosis, while genetic inhibition of TARS2 restores mitochondrial function, reduces apoptosis, and improves cardiac performance.\",\n      \"method\": \"TARS2 overexpression and genetic inhibition in cardiomyocytes, mitochondrial ROS measurement, apoptosis assays, cardiac function assessment\",\n      \"journal\": \"JACC. Basic to translational science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — gain- and loss-of-function experiments with defined mitochondrial and apoptotic readouts, but single lab and abstract provides limited methodological detail\",\n      \"pmids\": [\"42048853\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"TARS2 is a mitochondrial threonyl-tRNA synthetase that charges tRNAThr and edits mischarged Ser-tRNAThr for mitochondrial translation; beyond its canonical tRNA synthetase role, it acts as a nutrient sensor by interacting with inactive Rag GTPases (particularly GTP-RagC) to promote RagA GTP-loading and thereby activate mTORC1 in response to threonine availability, with pathogenic loss-of-function variants causing combined oxidative phosphorylation deficiency by impairing both mitochondrial translation and mTORC1 signaling.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"TARS2 is a mitochondrial threonyl-tRNA synthetase that supports mitochondrial translation and, separately, acts as a threonine sensor coupling nutrient availability to mTORC1 signaling [#0, #1]. In its canonical role, TARS2 charges mitochondrial tRNAThr and clears mischarged Ser-tRNAThr, and pathogenic mutations that reduce TARS2 protein levels and aminoacylation function lower mitochondrial threonyl-tRNA and impair mitochondrial respiration, a defect rescued by re-expression of wild-type TARS2 in patient fibroblasts [#0, #2]. Beyond aminoacylation, TARS2 interacts with inactive Rag GTPases—particularly GTP-loaded RagC—to promote GTP-loading of RagA and thereby activate mTORC1 in response to threonine, an effect specific to TARS2 and not shared by the cytoplasmic enzyme TARS [#1]. This signaling function maps to the TARS2 301–381 region, where pathogenic variants disrupt Rag binding and mTORC1 activation, with a zebrafish tars2 model recapitulating the human phenotype and downstream mTORC1 dysregulation [#3]. Excess TARS2 in cardiomyocytes perturbs mitochondrial homeostasis and drives ROS-dependent apoptosis, whereas its inhibition restores mitochondrial function and cardiac performance [#4].\",\n  \"teleology\": [\n    {\n      \"year\": 2014,\n      \"claim\": \"Established that TARS2 is required for mitochondrial respiration via its role in mitochondrial threonyl-tRNA charging, linking loss-of-function variants to a respiratory chain defect.\",\n      \"evidence\": \"Whole-exome sequencing, protein and tRNA quantification, and rescue by wild-type transcript in patient fibroblasts\",\n      \"pmids\": [\"24827421\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not resolve the editing/deacylation activity of the enzyme\", \"Did not address any extra-translational function\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Revealed a moonlighting function distinct from aminoacylation: TARS2 senses threonine and activates mTORC1 through Rag GTPase engagement, separating this role from the cytoplasmic synthetase.\",\n      \"evidence\": \"Reciprocal Co-IP with Rag GTPases, RagA GTP-loading assays, and TARS2 knockout cells with mTORC1 readouts; TARS negative control\",\n      \"pmids\": [\"33340489\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of the TARS2–RagC interaction not defined\", \"Whether aminoacylation and Rag-binding functions are mutually exclusive not resolved\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Defined the dual catalytic role of TARS2 in generating Thr-tRNAThr and clearing mischarged Ser-tRNAThr, and showed pathogenic variants act by destabilizing the protein or impairing aminoacylation.\",\n      \"evidence\": \"Aminoacylation and protein stability assays with homology modeling of pathogenic variants\",\n      \"pmids\": [\"34508595\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Editing activity inferred without full reconstitution\", \"Single-lab functional characterization\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Mapped the Rag-binding determinant to residues 301–381 and demonstrated in vivo that disrupting this interaction dysregulates mTORC1 signaling.\",\n      \"evidence\": \"In vitro Rag-binding assays of TARS2 variants and a zebrafish tars2 loss-of-function model with mTORC1 target analysis\",\n      \"pmids\": [\"37454282\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Domain mapping from a single lab\", \"Relative contribution of translation vs mTORC1 defects to phenotype not dissected\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Linked TARS2 dosage to mitochondrial ROS and cardiomyocyte apoptosis, indicating that excess TARS2 is pathogenic in cardiac tissue.\",\n      \"evidence\": \"Gain- and loss-of-function in cardiomyocytes with mitochondrial ROS, apoptosis, and cardiac function readouts\",\n      \"pmids\": [\"42048853\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism connecting TARS2 overexpression to ROS not defined\", \"Single-lab study with limited methodological detail\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How the aminoacylation and mTORC1-signaling functions of TARS2 are mechanistically coordinated, and the structural basis of Rag GTPase engagement, remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model of the TARS2–Rag complex\", \"Whether threonine binding to the catalytic site gates Rag interaction unknown\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140098\", \"supporting_discovery_ids\": [0, 2]},\n      {\"term_id\": \"GO:0016740\", \"supporting_discovery_ids\": [0, 2]},\n      {\"term_id\": \"GO:0003723\", \"supporting_discovery_ids\": [0, 2]},\n      {\"term_id\": \"GO:0140299\", \"supporting_discovery_ids\": [1, 3]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [0, 4]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-392499\", \"supporting_discovery_ids\": [0, 2]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [1, 3]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"RagC\", \"RagA\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":5,"faith_total":5,"faith_pct":100.0}}