{"gene":"DHTKD1","run_date":"2026-06-09T23:54:42","timeline":{"discoveries":[{"year":2012,"finding":"DHTKD1 encodes the enzyme mediating the last unresolved step in the L-lysine degradation pathway — oxidative decarboxylation of 2-oxoadipate to glutaryl-CoA. Patient-derived fibroblasts with DHTKD1 loss-of-function mutations accumulated deuterium-labeled 2-oxoadipate, and lentiviral restoration of wild-type DHTKD1 normalized elevated 2-oxoadipate levels.","method":"Lentiviral complementation in patient fibroblasts, stable-isotope (deuterium-labeled) metabolite tracing, exome sequencing","journal":"American journal of human genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — functional complementation with isotope tracing in patient cells; replicated by subsequent independent studies confirming the same enzymatic function","pmids":["23141293"],"is_preprint":false},{"year":2012,"finding":"DHTKD1 is required for mitochondrial energy production; silencing DHTKD1 in cells significantly decreased ATP, total NAD+, NADH, and NADH levels, consistent with impaired mitochondrial respiratory chain activity.","method":"siRNA knockdown of DHTKD1 in transfected cells; biochemical measurement of ATP, NAD+, and NADH","journal":"American journal of human genetics","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — single lab, silencing approach with biochemical readouts but no reconstitution or structural data","pmids":["23141294"],"is_preprint":false},{"year":2013,"finding":"DHTKD1 knockdown impairs mitochondrial biogenesis and increases reactive oxygen species (ROS) production, leading to retarded cell growth and increased apoptosis; DHTKD1 expression level correlates directly with ATP production.","method":"siRNA knockdown; measurement of ATP, ROS, mitochondrial morphology, cell growth, and apoptosis assays","journal":"FEBS letters","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — single lab, multiple biochemical readouts but no reconstitution or structural data","pmids":["24076469"],"is_preprint":false},{"year":2018,"finding":"Loss of DHTKD1 in a mouse knockout model causes CMT2-like peripheral neuropathy phenotypes (progressive distal weakness, motor and sensory dysfunction, decreased nerve conduction velocity). Mechanistically, accumulated substrates 2-ketoadipic acid (2-KAA) and 2-aminoadipic acid (2-AAA) stimulate insulin secretion, and elevated insulin upregulates EGR2 in Schwann cells, which drives transcription of myelin protein zero (Mpz), leading to myelin damage and axonal degeneration. 2-AAA feeding reproduced CMT2Q-like phenotypes.","method":"Dhtkd1 knockout mouse model; electrophysiology; metabolite measurement in urine; insulin secretion assay; Schwann cell culture with Mpz/Egr2 expression analysis; 2-AAA feeding experiment","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — in vivo knockout + rescue by metabolite feeding + defined molecular pathway (2-AAA → insulin → EGR2 → Mpz) with multiple orthogonal methods","pmids":["29661920"],"is_preprint":false},{"year":2018,"finding":"DHTKD1 loss reduces mitochondrial function in esophageal epithelial cells and patient fibroblasts; loss of DHTKD1 increases ROS production and induces viperin expression, a gene involved in Th2 cytokine production.","method":"shRNA knockdown in esophageal epithelial cells; patient fibroblasts; mitochondrial function assays; ROS measurement; viperin expression analysis","journal":"JCI insight","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — single lab, shRNA and patient cells, multiple functional readouts","pmids":["29669943"],"is_preprint":false},{"year":2020,"finding":"DHTKD1 forms a hybrid 2-oxoglutaric and 2-oxoadipic acid dehydrogenase complex with OGDH (oxoglutarate dehydrogenase), DLST (dihydrolipoyl succinyltransferase), and DLD (dihydrolipoamide dehydrogenase). In glutaryl-CoA dehydrogenase-deficient HEK-293 cells, DHTKD1 loss reduces glutarylcarnitine 2-fold, while OGDH accounts for the remaining production, demonstrating substrate overlap between DHTKD1 and OGDH for 2-oxoadipate.","method":"Co-immunoprecipitation in HEK-293 cells; CRISPR KO; glutarylcarnitine measurement; hybrid complex characterization","journal":"Human molecular genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal complex identification with KO cells and quantitative metabolite readout; multiple orthogonal approaches in one study","pmids":["32160276"],"is_preprint":false},{"year":2020,"finding":"Crystal structure of human DHTKD1 solved at 1.9 Å resolution in complex with thiamine diphosphate (ThDP) cofactor. The active site is modeled on 2-oxoglutarate dehydrogenase but specifically engineered to preferentially accommodate the longer substrate 2-oxoadipate over 2-oxoglutarate. Disease-associated missense variants disrupt either DLST interaction or DHTKD1 protein stability.","method":"X-ray crystallography (1.9 Å); single-particle electron microscopy (4.7 Å reconstruction of DLST core); interaction studies with disease variants","journal":"IUCrJ","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure with functional interaction data and disease variant analysis; multiple structural and biochemical methods","pmids":["32695416"],"is_preprint":false},{"year":2020,"finding":"Crystal structure of DHTKD1 with ThDP at 2.25 Å; identification of adipoylphosphonic acid and tenatoprazole as DHTKD1 inhibitors. Most disease-associated missense variants showed impaired folding or reduced thermal stability combined with absent or reduced enzyme activity; three variants showed no biochemical abnormality.","method":"X-ray crystallography (2.25 Å); high-throughput and targeted compound screening; enzyme activity assays; thermal stability assays on 10 disease-associated variants","journal":"ACS chemical biology","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure + in vitro enzyme activity assays + mutagenesis panel in a single rigorous study","pmids":["32633484"],"is_preprint":false},{"year":2020,"finding":"Two DHTKD1 isoforms (~130 kDa and ~70 kDa) were identified in animal tissues by immunoblotting and mass spectrometry. The 70 kDa isoform is truncated at the N-terminus but retains the active site. These isoforms were not produced upon recombinant expression of human DHTKD1 in bacterial or yeast systems, suggesting animal-specific post-translational regulation. The N-terminal domain (absent in the 70 kDa form) is required for multienzyme complex assembly, implying the 70 kDa form may catalyze non-oxidative decarboxylation independently of the complex.","method":"Partial purification of animal OADH; immunoblotting; mass spectrometry; recombinant expression in bacterial and yeast systems; peptide mapping on protein structure","journal":"Biochemistry. Biokhimiia","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — MS identification and structural mapping in one study, but interpretation of functional significance of truncated isoform is partially speculative","pmids":["33045952"],"is_preprint":false},{"year":2020,"finding":"A knock-in mouse model with the Dhtkd1Y486* mutation shows reduced DHTKD1 expression in sciatic nerve, peripheral neuropathy with reduced large axon diameter, abnormal myelination, sensory defects, mitochondrial accumulation in peripheral nerves, and elevated energy metabolic state.","method":"Knock-in mouse model (Dhtkd1Y486* point mutation); histopathology; nerve conduction studies; sensory/motor behavioral testing; mitochondrial morphology analysis","journal":"Acta neuropathologica communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo knock-in model with multiple phenotypic readouts in single lab","pmids":["32169121"],"is_preprint":false},{"year":2021,"finding":"DHTKD1 knockout in HAP-1 cells impairs mitochondrial structure and function (reduced mitochondrial respiration, less ATP production). Compensatory mechanisms include increased mitochondrial content and activation of Akt, p38, and ERK signaling pathways, allowing maintenance of normal cell proliferation despite metabolic impairment.","method":"CRISPR KO in HAP-1 cells; Seahorse mitochondrial respiration assay; ATP measurement; Western blot for signaling pathways; mitochondrial content quantification","journal":"Frontiers in endocrinology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean KO with defined cellular phenotype and pathway identification, single lab","pmids":["34484123"],"is_preprint":false},{"year":2017,"finding":"In Dhtkd1-/-/Gcdh-/- double knockout mice, DHTKD1 inhibition alone does not rescue the glutaric aciduria type I (GA-I) phenotype; double knockouts show similar glutaric acid accumulation in brain and liver as Gcdh-/- single knockouts, indicating an alternative enzymatic source of glutaryl-CoA independent of DHTKD1.","method":"Double knockout mouse model; metabolite quantification in brain and liver; behavioral phenotyping","journal":"Biochimica et biophysica acta. Molecular basis of disease","confidence":"High","confidence_rationale":"Tier 2 / Strong — in vivo double knockout genetic epistasis experiment with biochemical metabolite quantification; negative result is itself mechanistically informative (alternative pathway to glutaryl-CoA exists)","pmids":["28545977"],"is_preprint":false}],"current_model":"DHTKD1 encodes the E1 component (2-oxoadipate dehydrogenase) of a mitochondrial 2-oxoacid dehydrogenase complex that catalyzes oxidative decarboxylation of 2-oxoadipate to glutaryl-CoA in the lysine/tryptophan catabolism pathway; its crystal structure (solved at 1.9–2.25 Å with ThDP cofactor) reveals an active site specifically engineered to prefer 2-oxoadipate over 2-oxoglutarate, and DHTKD1 physically interacts with OGDH, DLST, and DLD to form a hybrid megacomplex, with OGDH also capable of processing 2-oxoadipate when DHTKD1 is absent; loss of DHTKD1 function causes accumulation of 2-oxoadipate and 2-aminoadipate, impairs mitochondrial biogenesis, ATP production, and respiration, increases ROS, and in peripheral neurons triggers a downstream signaling cascade (elevated substrate → insulin → EGR2 → Mpz dysregulation) that causes demyelination and axonal degeneration underlying CMT2Q."},"narrative":{"mechanistic_narrative":"DHTKD1 encodes the E1 component (2-oxoadipate dehydrogenase) that catalyzes the last unresolved step of L-lysine and tryptophan catabolism — the thiamine diphosphate (ThDP)-dependent oxidative decarboxylation of 2-oxoadipate to glutaryl-CoA — established by functional complementation in patient fibroblasts where loss-of-function mutations cause accumulation of deuterium-labeled 2-oxoadipate that wild-type DHTKD1 restoration normalizes [PMID:23141293]. Crystal structures of human DHTKD1 bound to ThDP define an active site modeled on 2-oxoglutarate dehydrogenase but specifically remodeled to accommodate the longer 2-oxoadipate substrate, and most disease-associated missense variants act by impairing protein folding/thermal stability or by disrupting partner interaction rather than by abolishing catalysis directly [PMID:32695416, PMID:32633484]. Rather than acting alone, DHTKD1 assembles into a hybrid 2-oxoglutarate/2-oxoadipate dehydrogenase megacomplex with OGDH, DLST, and DLD, with OGDH providing a redundant route to glutaryl-CoA from 2-oxoadipate when DHTKD1 is absent [PMID:32160276]; this functional redundancy is reinforced in vivo, where DHTKD1 loss fails to rescue glutaric aciduria type I, indicating an alternative enzymatic source of glutaryl-CoA [PMID:28545977]. Loss of DHTKD1 broadly compromises mitochondrial energetics — reducing ATP and respiration, impairing mitochondrial biogenesis, and elevating ROS [PMID:23141294, PMID:24076469, PMID:34484123]. In peripheral nerve, DHTKD1 deficiency causes a CMT2Q-like neuropathy through a defined cascade in which accumulated 2-aminoadipate and 2-oxoadipate stimulate insulin secretion, elevating EGR2 in Schwann cells and dysregulating myelin protein zero (Mpz) to drive demyelination and axonal degeneration [PMID:29661920, PMID:32169121].","teleology":[{"year":2012,"claim":"Identified the enzyme responsible for the previously unresolved oxidative decarboxylation of 2-oxoadipate, completing the L-lysine degradation pathway and assigning DHTKD1 a defined metabolic function.","evidence":"Lentiviral complementation in patient fibroblasts with deuterium-labeled metabolite tracing and exome sequencing","pmids":["23141293"],"confidence":"High","gaps":["Did not resolve enzymatic mechanism or cofactor requirement directly","Did not establish complex membership or partner enzymes"]},{"year":2012,"claim":"Linked the catabolic defect to a bioenergetic consequence, showing DHTKD1 is required for mitochondrial energy production.","evidence":"siRNA knockdown in cells with biochemical measurement of ATP, NAD+, and NADH","pmids":["23141294"],"confidence":"Medium","gaps":["Knockdown rather than clean genetic null","Mechanistic link between metabolite block and respiratory chain impairment not defined"]},{"year":2013,"claim":"Extended the bioenergetic phenotype to mitochondrial biogenesis and oxidative stress, connecting DHTKD1 loss to ROS, impaired growth, and apoptosis.","evidence":"siRNA knockdown with ATP, ROS, mitochondrial morphology, growth, and apoptosis assays","pmids":["24076469"],"confidence":"Medium","gaps":["Single-lab knockdown without rescue","Causal ordering of ROS versus mitochondrial dysfunction unresolved"]},{"year":2017,"claim":"Tested whether blocking glutaryl-CoA production via DHTKD1 could rescue glutaric aciduria type I, revealing an alternative, DHTKD1-independent source of glutaryl-CoA.","evidence":"Dhtkd1-/-/Gcdh-/- double knockout mice with metabolite quantification in brain and liver","pmids":["28545977"],"confidence":"High","gaps":["Did not identify the alternative enzyme producing glutaryl-CoA","Tissue-specific contribution of the redundant route not quantified"]},{"year":2018,"claim":"Defined the molecular cascade by which DHTKD1 loss causes CMT2Q peripheral neuropathy, linking substrate accumulation to a signaling axis controlling myelination.","evidence":"Dhtkd1 knockout mouse with electrophysiology, metabolite/insulin assays, Schwann cell Mpz/Egr2 analysis, and 2-AAA feeding rescue","pmids":["29661920"],"confidence":"High","gaps":["Mechanism by which 2-AAA/2-KAA stimulate insulin secretion not defined","Relative contribution of metabolic versus signaling damage to axonal degeneration unclear"]},{"year":2018,"claim":"Showed DHTKD1 loss compromises mitochondrial function in additional epithelial cell contexts and links to viperin/Th2 cytokine biology.","evidence":"shRNA knockdown in esophageal epithelial cells and patient fibroblasts with mitochondrial function, ROS, and viperin readouts","pmids":["29669943"],"confidence":"Medium","gaps":["Mechanism connecting DHTKD1 to viperin induction not established","Knockdown approach without genetic rescue"]},{"year":2020,"claim":"Established that DHTKD1 functions within a hybrid 2-oxoglutarate/2-oxoadipate dehydrogenase megacomplex and that OGDH provides redundant 2-oxoadipate processing.","evidence":"Co-immunoprecipitation and CRISPR KO in HEK-293 cells with glutarylcarnitine quantification","pmids":["32160276"],"confidence":"High","gaps":["Stoichiometry and architecture of the hybrid complex not fully resolved by this study","Conditions favoring DHTKD1 versus OGDH usage in vivo unknown"]},{"year":2020,"claim":"Provided atomic-resolution structural basis for DHTKD1 substrate preference and explained how disease variants act.","evidence":"X-ray crystallography of DHTKD1-ThDP (1.9 Å) plus EM of DLST core and disease-variant interaction studies","pmids":["32695416"],"confidence":"High","gaps":["Full assembled megacomplex structure not solved at high resolution","Catalytic cycle intermediates not visualized"]},{"year":2020,"claim":"Confirmed substrate preference structurally, dissected the variant-folding/activity relationship, and identified the first DHTKD1 inhibitors.","evidence":"X-ray crystallography (2.25 Å), compound screening, enzyme activity, and thermal stability assays on a 10-variant panel","pmids":["32633484"],"confidence":"High","gaps":["Three variants with no biochemical abnormality remain mechanistically unexplained","In vivo efficacy/selectivity of identified inhibitors not established"]},{"year":2020,"claim":"Identified animal-specific DHTKD1 isoforms and proposed a complex-independent role for an N-terminally truncated form.","evidence":"Partial purification, immunoblotting, mass spectrometry, recombinant expression, and structural peptide mapping","pmids":["33045952"],"confidence":"Medium","gaps":["Functional role of the 70 kDa isoform inferred, not directly demonstrated","Post-translational mechanism generating the truncated form unknown"]},{"year":2020,"claim":"Validated a patient-relevant point mutation in vivo, recapitulating peripheral neuropathy with abnormal myelination and altered nerve mitochondria.","evidence":"Dhtkd1Y486* knock-in mouse with histopathology, nerve conduction, behavior, and mitochondrial morphology","pmids":["32169121"],"confidence":"Medium","gaps":["Did not independently confirm the insulin/EGR2/Mpz cascade","Mitochondrial accumulation versus dysfunction relationship in nerve unresolved"]},{"year":2021,"claim":"Characterized cellular compensation to DHTKD1 loss, showing mitochondrial dysfunction is buffered by increased mitochondrial content and survival signaling.","evidence":"CRISPR KO in HAP-1 cells with Seahorse respiration, ATP, mitochondrial content, and Akt/p38/ERK signaling analysis","pmids":["34484123"],"confidence":"Medium","gaps":["Trigger linking metabolic defect to Akt/p38/ERK activation not defined","Relevance of compensation to neuronal cell types not tested"]},{"year":null,"claim":"The identity of the DHTKD1-independent enzyme producing glutaryl-CoA, the signal coupling 2-oxoadipate accumulation to insulin secretion and survival kinase activation, and the in vivo function of the truncated isoform remain unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["Alternative glutaryl-CoA source unidentified","Sensor coupling substrate accumulation to insulin/EGR2 signaling unknown","Physiological role of 70 kDa isoform untested"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016829","term_label":"lyase activity","supporting_discovery_ids":[0,6,7]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[5]}],"localization":[{"term_id":"GO:0005739","term_label":"mitochondrion","supporting_discovery_ids":[1,2,10]}],"pathway":[{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[0,5]}],"complexes":["2-oxoglutarate/2-oxoadipate dehydrogenase hybrid complex"],"partners":["OGDH","DLST","DLD"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q96HY7","full_name":"2-oxoadipate dehydrogenase complex component E1","aliases":["2-oxoadipate dehydrogenase, mitochondrial","Alpha-ketoadipate dehydrogenase","Alpha-KADH-E1","Dehydrogenase E1 and transketolase domain-containing protein 1","Probable 2-oxoglutarate dehydrogenase E1 component DHKTD1, mitochondrial"],"length_aa":919,"mass_kda":103.1,"function":"2-oxoadipate dehydrogenase (E1a) component of the 2-oxoadipate dehydrogenase complex (OADHC) (PubMed:29191460, PubMed:29752936, PubMed:32303640, PubMed:32633484, PubMed:32695416). Participates in the first step, rate limiting for the overall conversion of 2-oxoadipate (alpha-ketoadipate) to glutaryl-CoA and CO(2) catalyzed by the whole OADHC (PubMed:29191460, PubMed:32695416). Catalyzes the irreversible decarboxylation of 2-oxoadipate via the thiamine diphosphate (ThDP) cofactor and subsequent transfer of the decarboxylated acyl intermediate on an oxidized dihydrolipoyl group that is covalently amidated to the E2 enzyme (dihydrolipoyllysine-residue succinyltransferase or DLST) (Probable) (PubMed:29752936, PubMed:32303640, PubMed:32633484). Can catalyze the decarboxylation of 2-oxoglutarate in vitro, but at a much lower rate than 2-oxoadipate (PubMed:29191460, PubMed:29752936, PubMed:32633484, PubMed:32695416). Responsible for the last step of L-lysine, L-hydroxylysine and L-tryptophan catabolism with the common product being 2-oxoadipate (Probable)","subcellular_location":"Mitochondrion","url":"https://www.uniprot.org/uniprotkb/Q96HY7/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/DHTKD1","classification":"Not Classified","n_dependent_lines":0,"n_total_lines":1208,"dependency_fraction":0.0},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/DHTKD1","total_profiled":1310},"omim":[{"mim_id":"618811","title":"MITOCHONDRIAL DNA DEPLETION SYNDROME 18; MTDPS18","url":"https://www.omim.org/entry/618811"},{"mim_id":"617513","title":"OXOGLUTARATE DEHYDROGENASE-LIKE PROTEIN; OGDHL","url":"https://www.omim.org/entry/617513"},{"mim_id":"615025","title":"CHARCOT-MARIE-TOOTH DISEASE, AXONAL, TYPE 2Q; CMT2Q","url":"https://www.omim.org/entry/615025"},{"mim_id":"614984","title":"DEHYDROGENASE E1 AND TRANSKETOLASE DOMAINS-CONTAINING PROTEIN 1; DHTKD1","url":"https://www.omim.org/entry/614984"},{"mim_id":"608801","title":"GLUTARYL-CoA DEHYDROGENASE; GCDH","url":"https://www.omim.org/entry/608801"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Mitochondria","reliability":"Supported"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in all","driving_tissues":[{"tissue":"liver","ntpm":121.0}],"url":"https://www.proteinatlas.org/search/DHTKD1"},"hgnc":{"alias_symbol":["KIAA1630","MGC3090","DKFZP762M115","CMT2Q","OADC-E1","OADH-E1","E1a"],"prev_symbol":[]},"alphafold":{"accession":"Q96HY7","domains":[{"cath_id":"-","chopping":"55-140","consensus_level":"high","plddt":94.1351,"start":55,"end":140},{"cath_id":"3.40.50.970","chopping":"160-499","consensus_level":"high","plddt":97.9413,"start":160,"end":499},{"cath_id":"3.40.50.12470","chopping":"529-783","consensus_level":"high","plddt":98.2747,"start":529,"end":783},{"cath_id":"3.40.50.11610","chopping":"794-919","consensus_level":"high","plddt":98.3237,"start":794,"end":919}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q96HY7","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q96HY7-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q96HY7-F1-predicted_aligned_error_v6.png","plddt_mean":95.06},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=DHTKD1","jax_strain_url":"https://www.jax.org/strain/search?query=DHTKD1"},"sequence":{"accession":"Q96HY7","fasta_url":"https://rest.uniprot.org/uniprotkb/Q96HY7.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q96HY7/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q96HY7"}},"corpus_meta":[{"pmid":"23141293","id":"PMC_23141293","title":"DHTKD1 mutations cause 2-aminoadipic and 2-oxoadipic aciduria.","date":"2012","source":"American journal of human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/23141293","citation_count":88,"is_preprint":false},{"pmid":"23141294","id":"PMC_23141294","title":"A nonsense mutation in DHTKD1 causes Charcot-Marie-Tooth disease type 2 in a large Chinese pedigree.","date":"2012","source":"American journal of human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/23141294","citation_count":59,"is_preprint":false},{"pmid":"24076469","id":"PMC_24076469","title":"DHTKD1 is essential for mitochondrial biogenesis and function maintenance.","date":"2013","source":"FEBS letters","url":"https://pubmed.ncbi.nlm.nih.gov/24076469","citation_count":55,"is_preprint":false},{"pmid":"29669943","id":"PMC_29669943","title":"Whole-exome sequencing uncovers oxidoreductases DHTKD1 and OGDHL as linkers between mitochondrial dysfunction and eosinophilic esophagitis.","date":"2018","source":"JCI insight","url":"https://pubmed.ncbi.nlm.nih.gov/29669943","citation_count":46,"is_preprint":false},{"pmid":"28545977","id":"PMC_28545977","title":"Elevated glutaric acid levels in Dhtkd1-/Gcdh- double knockout mice challenge our current understanding of lysine metabolism.","date":"2017","source":"Biochimica et biophysica acta. Molecular basis of disease","url":"https://pubmed.ncbi.nlm.nih.gov/28545977","citation_count":44,"is_preprint":false},{"pmid":"26141459","id":"PMC_26141459","title":"New Cases of DHTKD1 Mutations in Patients with 2-Ketoadipic Aciduria.","date":"2015","source":"JIMD reports","url":"https://pubmed.ncbi.nlm.nih.gov/26141459","citation_count":29,"is_preprint":false},{"pmid":"29661920","id":"PMC_29661920","title":"DHTKD1 Deficiency Causes Charcot-Marie-Tooth Disease in Mice.","date":"2018","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/29661920","citation_count":28,"is_preprint":false},{"pmid":"32160276","id":"PMC_32160276","title":"DHTKD1 and OGDH display substrate overlap in cultured cells and form a hybrid 2-oxo acid dehydrogenase complex in vivo.","date":"2020","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/32160276","citation_count":26,"is_preprint":false},{"pmid":"34484123","id":"PMC_34484123","title":"Knock-Out of DHTKD1 Alters Mitochondrial Respiration and Function, and May Represent a Novel Pathway in Cardiometabolic Disease Risk.","date":"2021","source":"Frontiers in endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/34484123","citation_count":20,"is_preprint":false},{"pmid":"32695416","id":"PMC_32695416","title":"Crystal structure and interaction studies of human DHTKD1 provide insight into a mitochondrial megacomplex in lysine catabolism.","date":"2020","source":"IUCrJ","url":"https://pubmed.ncbi.nlm.nih.gov/32695416","citation_count":20,"is_preprint":false},{"pmid":"32633484","id":"PMC_32633484","title":"Inhibition and Crystal Structure of the Human DHTKD1-Thiamin Diphosphate Complex.","date":"2020","source":"ACS chemical biology","url":"https://pubmed.ncbi.nlm.nih.gov/32633484","citation_count":14,"is_preprint":false},{"pmid":"32169121","id":"PMC_32169121","title":"CMT2Q-causing mutation in the Dhtkd1 gene lead to sensory defects, mitochondrial accumulation and altered metabolism in a knock-in mouse model.","date":"2020","source":"Acta neuropathologica communications","url":"https://pubmed.ncbi.nlm.nih.gov/32169121","citation_count":12,"is_preprint":false},{"pmid":"35052424","id":"PMC_35052424","title":"Heterozygous DHTKD1 Variants in Two European Cohorts of Amyotrophic Lateral Sclerosis Patients.","date":"2021","source":"Genes","url":"https://pubmed.ncbi.nlm.nih.gov/35052424","citation_count":9,"is_preprint":false},{"pmid":"33045952","id":"PMC_33045952","title":"Isoforms of the DHTKD1-Encoded 2-Oxoadipate Dehydrogenase, Identified in Animal Tissues, Are not Observed upon the Human DHTKD1 Expression in Bacterial or Yeast Systems.","date":"2020","source":"Biochemistry. 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Patient-derived fibroblasts with DHTKD1 loss-of-function mutations accumulated deuterium-labeled 2-oxoadipate, and lentiviral restoration of wild-type DHTKD1 normalized elevated 2-oxoadipate levels.\",\n      \"method\": \"Lentiviral complementation in patient fibroblasts, stable-isotope (deuterium-labeled) metabolite tracing, exome sequencing\",\n      \"journal\": \"American journal of human genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — functional complementation with isotope tracing in patient cells; replicated by subsequent independent studies confirming the same enzymatic function\",\n      \"pmids\": [\"23141293\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"DHTKD1 is required for mitochondrial energy production; silencing DHTKD1 in cells significantly decreased ATP, total NAD+, NADH, and NADH levels, consistent with impaired mitochondrial respiratory chain activity.\",\n      \"method\": \"siRNA knockdown of DHTKD1 in transfected cells; biochemical measurement of ATP, NAD+, and NADH\",\n      \"journal\": \"American journal of human genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — single lab, silencing approach with biochemical readouts but no reconstitution or structural data\",\n      \"pmids\": [\"23141294\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"DHTKD1 knockdown impairs mitochondrial biogenesis and increases reactive oxygen species (ROS) production, leading to retarded cell growth and increased apoptosis; DHTKD1 expression level correlates directly with ATP production.\",\n      \"method\": \"siRNA knockdown; measurement of ATP, ROS, mitochondrial morphology, cell growth, and apoptosis assays\",\n      \"journal\": \"FEBS letters\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — single lab, multiple biochemical readouts but no reconstitution or structural data\",\n      \"pmids\": [\"24076469\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Loss of DHTKD1 in a mouse knockout model causes CMT2-like peripheral neuropathy phenotypes (progressive distal weakness, motor and sensory dysfunction, decreased nerve conduction velocity). Mechanistically, accumulated substrates 2-ketoadipic acid (2-KAA) and 2-aminoadipic acid (2-AAA) stimulate insulin secretion, and elevated insulin upregulates EGR2 in Schwann cells, which drives transcription of myelin protein zero (Mpz), leading to myelin damage and axonal degeneration. 2-AAA feeding reproduced CMT2Q-like phenotypes.\",\n      \"method\": \"Dhtkd1 knockout mouse model; electrophysiology; metabolite measurement in urine; insulin secretion assay; Schwann cell culture with Mpz/Egr2 expression analysis; 2-AAA feeding experiment\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — in vivo knockout + rescue by metabolite feeding + defined molecular pathway (2-AAA → insulin → EGR2 → Mpz) with multiple orthogonal methods\",\n      \"pmids\": [\"29661920\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"DHTKD1 loss reduces mitochondrial function in esophageal epithelial cells and patient fibroblasts; loss of DHTKD1 increases ROS production and induces viperin expression, a gene involved in Th2 cytokine production.\",\n      \"method\": \"shRNA knockdown in esophageal epithelial cells; patient fibroblasts; mitochondrial function assays; ROS measurement; viperin expression analysis\",\n      \"journal\": \"JCI insight\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — single lab, shRNA and patient cells, multiple functional readouts\",\n      \"pmids\": [\"29669943\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"DHTKD1 forms a hybrid 2-oxoglutaric and 2-oxoadipic acid dehydrogenase complex with OGDH (oxoglutarate dehydrogenase), DLST (dihydrolipoyl succinyltransferase), and DLD (dihydrolipoamide dehydrogenase). In glutaryl-CoA dehydrogenase-deficient HEK-293 cells, DHTKD1 loss reduces glutarylcarnitine 2-fold, while OGDH accounts for the remaining production, demonstrating substrate overlap between DHTKD1 and OGDH for 2-oxoadipate.\",\n      \"method\": \"Co-immunoprecipitation in HEK-293 cells; CRISPR KO; glutarylcarnitine measurement; hybrid complex characterization\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal complex identification with KO cells and quantitative metabolite readout; multiple orthogonal approaches in one study\",\n      \"pmids\": [\"32160276\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Crystal structure of human DHTKD1 solved at 1.9 Å resolution in complex with thiamine diphosphate (ThDP) cofactor. The active site is modeled on 2-oxoglutarate dehydrogenase but specifically engineered to preferentially accommodate the longer substrate 2-oxoadipate over 2-oxoglutarate. Disease-associated missense variants disrupt either DLST interaction or DHTKD1 protein stability.\",\n      \"method\": \"X-ray crystallography (1.9 Å); single-particle electron microscopy (4.7 Å reconstruction of DLST core); interaction studies with disease variants\",\n      \"journal\": \"IUCrJ\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure with functional interaction data and disease variant analysis; multiple structural and biochemical methods\",\n      \"pmids\": [\"32695416\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Crystal structure of DHTKD1 with ThDP at 2.25 Å; identification of adipoylphosphonic acid and tenatoprazole as DHTKD1 inhibitors. Most disease-associated missense variants showed impaired folding or reduced thermal stability combined with absent or reduced enzyme activity; three variants showed no biochemical abnormality.\",\n      \"method\": \"X-ray crystallography (2.25 Å); high-throughput and targeted compound screening; enzyme activity assays; thermal stability assays on 10 disease-associated variants\",\n      \"journal\": \"ACS chemical biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure + in vitro enzyme activity assays + mutagenesis panel in a single rigorous study\",\n      \"pmids\": [\"32633484\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Two DHTKD1 isoforms (~130 kDa and ~70 kDa) were identified in animal tissues by immunoblotting and mass spectrometry. The 70 kDa isoform is truncated at the N-terminus but retains the active site. These isoforms were not produced upon recombinant expression of human DHTKD1 in bacterial or yeast systems, suggesting animal-specific post-translational regulation. The N-terminal domain (absent in the 70 kDa form) is required for multienzyme complex assembly, implying the 70 kDa form may catalyze non-oxidative decarboxylation independently of the complex.\",\n      \"method\": \"Partial purification of animal OADH; immunoblotting; mass spectrometry; recombinant expression in bacterial and yeast systems; peptide mapping on protein structure\",\n      \"journal\": \"Biochemistry. Biokhimiia\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — MS identification and structural mapping in one study, but interpretation of functional significance of truncated isoform is partially speculative\",\n      \"pmids\": [\"33045952\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"A knock-in mouse model with the Dhtkd1Y486* mutation shows reduced DHTKD1 expression in sciatic nerve, peripheral neuropathy with reduced large axon diameter, abnormal myelination, sensory defects, mitochondrial accumulation in peripheral nerves, and elevated energy metabolic state.\",\n      \"method\": \"Knock-in mouse model (Dhtkd1Y486* point mutation); histopathology; nerve conduction studies; sensory/motor behavioral testing; mitochondrial morphology analysis\",\n      \"journal\": \"Acta neuropathologica communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo knock-in model with multiple phenotypic readouts in single lab\",\n      \"pmids\": [\"32169121\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"DHTKD1 knockout in HAP-1 cells impairs mitochondrial structure and function (reduced mitochondrial respiration, less ATP production). Compensatory mechanisms include increased mitochondrial content and activation of Akt, p38, and ERK signaling pathways, allowing maintenance of normal cell proliferation despite metabolic impairment.\",\n      \"method\": \"CRISPR KO in HAP-1 cells; Seahorse mitochondrial respiration assay; ATP measurement; Western blot for signaling pathways; mitochondrial content quantification\",\n      \"journal\": \"Frontiers in endocrinology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean KO with defined cellular phenotype and pathway identification, single lab\",\n      \"pmids\": [\"34484123\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"In Dhtkd1-/-/Gcdh-/- double knockout mice, DHTKD1 inhibition alone does not rescue the glutaric aciduria type I (GA-I) phenotype; double knockouts show similar glutaric acid accumulation in brain and liver as Gcdh-/- single knockouts, indicating an alternative enzymatic source of glutaryl-CoA independent of DHTKD1.\",\n      \"method\": \"Double knockout mouse model; metabolite quantification in brain and liver; behavioral phenotyping\",\n      \"journal\": \"Biochimica et biophysica acta. Molecular basis of disease\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — in vivo double knockout genetic epistasis experiment with biochemical metabolite quantification; negative result is itself mechanistically informative (alternative pathway to glutaryl-CoA exists)\",\n      \"pmids\": [\"28545977\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"DHTKD1 encodes the E1 component (2-oxoadipate dehydrogenase) of a mitochondrial 2-oxoacid dehydrogenase complex that catalyzes oxidative decarboxylation of 2-oxoadipate to glutaryl-CoA in the lysine/tryptophan catabolism pathway; its crystal structure (solved at 1.9–2.25 Å with ThDP cofactor) reveals an active site specifically engineered to prefer 2-oxoadipate over 2-oxoglutarate, and DHTKD1 physically interacts with OGDH, DLST, and DLD to form a hybrid megacomplex, with OGDH also capable of processing 2-oxoadipate when DHTKD1 is absent; loss of DHTKD1 function causes accumulation of 2-oxoadipate and 2-aminoadipate, impairs mitochondrial biogenesis, ATP production, and respiration, increases ROS, and in peripheral neurons triggers a downstream signaling cascade (elevated substrate → insulin → EGR2 → Mpz dysregulation) that causes demyelination and axonal degeneration underlying CMT2Q.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"DHTKD1 encodes the E1 component (2-oxoadipate dehydrogenase) that catalyzes the last unresolved step of L-lysine and tryptophan catabolism — the thiamine diphosphate (ThDP)-dependent oxidative decarboxylation of 2-oxoadipate to glutaryl-CoA — established by functional complementation in patient fibroblasts where loss-of-function mutations cause accumulation of deuterium-labeled 2-oxoadipate that wild-type DHTKD1 restoration normalizes [#0]. Crystal structures of human DHTKD1 bound to ThDP define an active site modeled on 2-oxoglutarate dehydrogenase but specifically remodeled to accommodate the longer 2-oxoadipate substrate, and most disease-associated missense variants act by impairing protein folding/thermal stability or by disrupting partner interaction rather than by abolishing catalysis directly [#6, #7]. Rather than acting alone, DHTKD1 assembles into a hybrid 2-oxoglutarate/2-oxoadipate dehydrogenase megacomplex with OGDH, DLST, and DLD, with OGDH providing a redundant route to glutaryl-CoA from 2-oxoadipate when DHTKD1 is absent [#5]; this functional redundancy is reinforced in vivo, where DHTKD1 loss fails to rescue glutaric aciduria type I, indicating an alternative enzymatic source of glutaryl-CoA [#11]. Loss of DHTKD1 broadly compromises mitochondrial energetics — reducing ATP and respiration, impairing mitochondrial biogenesis, and elevating ROS [#1, #2, #10]. In peripheral nerve, DHTKD1 deficiency causes a CMT2Q-like neuropathy through a defined cascade in which accumulated 2-aminoadipate and 2-oxoadipate stimulate insulin secretion, elevating EGR2 in Schwann cells and dysregulating myelin protein zero (Mpz) to drive demyelination and axonal degeneration [#3, #9].\",\n  \"teleology\": [\n    {\n      \"year\": 2012,\n      \"claim\": \"Identified the enzyme responsible for the previously unresolved oxidative decarboxylation of 2-oxoadipate, completing the L-lysine degradation pathway and assigning DHTKD1 a defined metabolic function.\",\n      \"evidence\": \"Lentiviral complementation in patient fibroblasts with deuterium-labeled metabolite tracing and exome sequencing\",\n      \"pmids\": [\"23141293\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not resolve enzymatic mechanism or cofactor requirement directly\", \"Did not establish complex membership or partner enzymes\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Linked the catabolic defect to a bioenergetic consequence, showing DHTKD1 is required for mitochondrial energy production.\",\n      \"evidence\": \"siRNA knockdown in cells with biochemical measurement of ATP, NAD+, and NADH\",\n      \"pmids\": [\"23141294\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Knockdown rather than clean genetic null\", \"Mechanistic link between metabolite block and respiratory chain impairment not defined\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Extended the bioenergetic phenotype to mitochondrial biogenesis and oxidative stress, connecting DHTKD1 loss to ROS, impaired growth, and apoptosis.\",\n      \"evidence\": \"siRNA knockdown with ATP, ROS, mitochondrial morphology, growth, and apoptosis assays\",\n      \"pmids\": [\"24076469\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab knockdown without rescue\", \"Causal ordering of ROS versus mitochondrial dysfunction unresolved\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Tested whether blocking glutaryl-CoA production via DHTKD1 could rescue glutaric aciduria type I, revealing an alternative, DHTKD1-independent source of glutaryl-CoA.\",\n      \"evidence\": \"Dhtkd1-/-/Gcdh-/- double knockout mice with metabolite quantification in brain and liver\",\n      \"pmids\": [\"28545977\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not identify the alternative enzyme producing glutaryl-CoA\", \"Tissue-specific contribution of the redundant route not quantified\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Defined the molecular cascade by which DHTKD1 loss causes CMT2Q peripheral neuropathy, linking substrate accumulation to a signaling axis controlling myelination.\",\n      \"evidence\": \"Dhtkd1 knockout mouse with electrophysiology, metabolite/insulin assays, Schwann cell Mpz/Egr2 analysis, and 2-AAA feeding rescue\",\n      \"pmids\": [\"29661920\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism by which 2-AAA/2-KAA stimulate insulin secretion not defined\", \"Relative contribution of metabolic versus signaling damage to axonal degeneration unclear\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Showed DHTKD1 loss compromises mitochondrial function in additional epithelial cell contexts and links to viperin/Th2 cytokine biology.\",\n      \"evidence\": \"shRNA knockdown in esophageal epithelial cells and patient fibroblasts with mitochondrial function, ROS, and viperin readouts\",\n      \"pmids\": [\"29669943\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism connecting DHTKD1 to viperin induction not established\", \"Knockdown approach without genetic rescue\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Established that DHTKD1 functions within a hybrid 2-oxoglutarate/2-oxoadipate dehydrogenase megacomplex and that OGDH provides redundant 2-oxoadipate processing.\",\n      \"evidence\": \"Co-immunoprecipitation and CRISPR KO in HEK-293 cells with glutarylcarnitine quantification\",\n      \"pmids\": [\"32160276\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Stoichiometry and architecture of the hybrid complex not fully resolved by this study\", \"Conditions favoring DHTKD1 versus OGDH usage in vivo unknown\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Provided atomic-resolution structural basis for DHTKD1 substrate preference and explained how disease variants act.\",\n      \"evidence\": \"X-ray crystallography of DHTKD1-ThDP (1.9 Å) plus EM of DLST core and disease-variant interaction studies\",\n      \"pmids\": [\"32695416\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Full assembled megacomplex structure not solved at high resolution\", \"Catalytic cycle intermediates not visualized\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Confirmed substrate preference structurally, dissected the variant-folding/activity relationship, and identified the first DHTKD1 inhibitors.\",\n      \"evidence\": \"X-ray crystallography (2.25 Å), compound screening, enzyme activity, and thermal stability assays on a 10-variant panel\",\n      \"pmids\": [\"32633484\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Three variants with no biochemical abnormality remain mechanistically unexplained\", \"In vivo efficacy/selectivity of identified inhibitors not established\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Identified animal-specific DHTKD1 isoforms and proposed a complex-independent role for an N-terminally truncated form.\",\n      \"evidence\": \"Partial purification, immunoblotting, mass spectrometry, recombinant expression, and structural peptide mapping\",\n      \"pmids\": [\"33045952\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional role of the 70 kDa isoform inferred, not directly demonstrated\", \"Post-translational mechanism generating the truncated form unknown\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Validated a patient-relevant point mutation in vivo, recapitulating peripheral neuropathy with abnormal myelination and altered nerve mitochondria.\",\n      \"evidence\": \"Dhtkd1Y486* knock-in mouse with histopathology, nerve conduction, behavior, and mitochondrial morphology\",\n      \"pmids\": [\"32169121\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Did not independently confirm the insulin/EGR2/Mpz cascade\", \"Mitochondrial accumulation versus dysfunction relationship in nerve unresolved\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Characterized cellular compensation to DHTKD1 loss, showing mitochondrial dysfunction is buffered by increased mitochondrial content and survival signaling.\",\n      \"evidence\": \"CRISPR KO in HAP-1 cells with Seahorse respiration, ATP, mitochondrial content, and Akt/p38/ERK signaling analysis\",\n      \"pmids\": [\"34484123\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Trigger linking metabolic defect to Akt/p38/ERK activation not defined\", \"Relevance of compensation to neuronal cell types not tested\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The identity of the DHTKD1-independent enzyme producing glutaryl-CoA, the signal coupling 2-oxoadipate accumulation to insulin secretion and survival kinase activation, and the in vivo function of the truncated isoform remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Alternative glutaryl-CoA source unidentified\", \"Sensor coupling substrate accumulation to insulin/EGR2 signaling unknown\", \"Physiological role of 70 kDa isoform untested\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016829\", \"supporting_discovery_ids\": [0, 6, 7]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [5]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [1, 2, 10]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [0, 5]}\n    ],\n    \"complexes\": [\"2-oxoglutarate/2-oxoadipate dehydrogenase hybrid complex\"],\n    \"partners\": [\"OGDH\", \"DLST\", \"DLD\"],\n    \"other_free_text\": []\n  }\n}\n```","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":4,"faith_total":5,"faith_pct":80.0}}