{"gene":"GDAP1","run_date":"2026-04-28T18:06:52","timeline":{"discoveries":[{"year":2005,"finding":"GDAP1 localizes to the mitochondrial outer membrane, with C-terminal transmembrane domains necessary for correct mitochondrial targeting. Overexpression of GDAP1 induces mitochondrial fragmentation, suggesting a role in the fission pathway of mitochondrial network dynamics.","method":"Transient overexpression, co-localization with organelle markers in COS-7 cells, western blot of subcellular fractions, C-terminal domain deletion analysis","journal":"Human molecular genetics","confidence":"High","confidence_rationale":"Tier 2 — direct localization experiment with functional consequence, replicated across multiple methods and cell lines","pmids":["15772096"],"is_preprint":false},{"year":2009,"finding":"GDAP1 is a mitochondrial fission factor whose activity is dependent on the fission factors Drp1 and Fis1. Recessively inherited CMT mutations reduce fission activity, while dominantly inherited mutations interfere with mitochondrial fusion and increase ROS production and apoptosis susceptibility.","method":"GDAP1 overexpression and knockdown in cells, mitochondrial morphology assays, ROS measurement, apoptosis assays, epistasis with Drp1 and Fis1","journal":"Neurobiology of disease","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods including KD/OE with defined phenotypic readouts and genetic epistasis","pmids":["19782751"],"is_preprint":false},{"year":2009,"finding":"GDAP1 is a tail-anchored mitochondrial outer membrane protein. A single transmembrane domain (TMD) together with adjacent basic amino acids is critical for MOM targeting. Basic amino acids bordering the TMD in the cytoplasm are required for both targeting and GDAP1-mediated fission function.","method":"Domain mutagenesis, subcellular fractionation, mitochondrial morphology assays, deletion and chimeric constructs","journal":"PloS one","confidence":"High","confidence_rationale":"Tier 1-2 — systematic mutagenesis with functional validation of targeting and fission activity","pmids":["19340293"],"is_preprint":false},{"year":2003,"finding":"GDAP1 protein shows sequence similarity to glutathione S-transferases (GSTs) and contains an extended region in GST domain II absent in most GSTs, plus C-terminal transmembrane domains. GDAP1 and its paralogue GDAP1L1 define a novel class of GST-related genes.","method":"Comparative genomics, sequence analysis, structural domain prediction","journal":"Molecular biology and evolution","confidence":"Medium","confidence_rationale":"Tier 4 — computational/comparative genomics analysis, but foundational for understanding domain architecture","pmids":["14595091"],"is_preprint":false},{"year":2013,"finding":"GDAP1 silencing causes abnormal mitochondrial distribution, reduces mitochondrial-ER contacts, and decreases store-operated Ca2+ entry (SOCE) following ER-Ca2+ mobilization. GDAP1 interacts with vesicle-organelle trafficking proteins RAB6B and caytaxin, suggesting a role in mitochondrial movement.","method":"siRNA knockdown in SH-SY5Y cells, co-immunoprecipitation, Ca2+ imaging, mitochondrial distribution analysis, ER-mitochondria contact site quantification","journal":"Neurobiology of disease","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods including Co-IP for interaction partners and functional Ca2+ measurements with defined cellular phenotype","pmids":["23542510"],"is_preprint":false},{"year":2013,"finding":"GDAP1 localizes to peroxisomes in addition to mitochondria, mediated by the import receptor Pex19. GDAP1 knockdown causes peroxisomal elongation rescued by re-expression. GDAP1-induced peroxisomal fission depends on integrity of hydrophobic domain 1 (HD1) and on Drp1 and Mff, similar to mitochondrial fission.","method":"Immunofluorescence co-localization, siRNA knockdown, rescue experiments with wild-type and CMT mutant GDAP1, epistasis with Drp1 and Mff","journal":"EMBO reports","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods with functional rescue experiments and genetic epistasis","pmids":["23628762"],"is_preprint":false},{"year":2011,"finding":"GDAP1 overexpression increases total cellular glutathione (GSH) content and mitochondrial membrane potential. GDAP1 knockdown increases susceptibility to GSH depletion. CMT-causing recessive mutations with reduced fission activity fail to increase GSH, linking GDAP1's potential GST activity to oxidative stress protection.","method":"Overexpression and siRNA knockdown in neuronal cell lines (HT22, NSC34), glutathione measurement, mitochondrial membrane potential assay, analysis of CMT patient fibroblasts","journal":"Human molecular genetics","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods in multiple cell types including patient-derived cells","pmids":["21965300"],"is_preprint":false},{"year":2014,"finding":"GDAP1L1, the paralogue of GDAP1 expressed in the CNS, responds to elevated oxidized glutathione by translocating from the cytosol to mitochondria and inserting into the mitochondrial outer membrane, compensating for GDAP1 loss in the CNS of Gdap1 knockout mice.","method":"Gdap1 knockout mouse model, subcellular fractionation, western blot, comparison of CNS vs PNS","journal":"Brain : a journal of neurology","confidence":"High","confidence_rationale":"Tier 2 — in vivo knockout model with biochemical validation of GDAP1L1 translocation mechanism","pmids":["24480485"],"is_preprint":false},{"year":2014,"finding":"In Gdap1 knockout mice, intra-axonal mitochondria of peripheral neurons are larger and mitochondrial transport is impaired in cultured sensory neurons. Loss of Gdap1 in Schwann cells recapitulates hypomyelinating peripheral neuropathy, demonstrating cell-autonomous function in Schwann cells.","method":"Gdap1 conditional and constitutive knockout mice, live-cell mitochondrial transport imaging, morphological analysis","journal":"Brain : a journal of neurology","confidence":"High","confidence_rationale":"Tier 2 — in vivo knockout model with direct live-cell imaging and cell-type-specific phenotypic analysis","pmids":["24480485"],"is_preprint":false},{"year":2015,"finding":"Loss of GDAP1 in knockout mice results in large and defective mitochondria in motor neurons, changes in ER cisternae, reduced cytoskeletal α-tubulin acetylation, increased autophagy, reduced cytosolic calcium, and reduced SOCE response, consistent with impaired mitochondria-ER interaction.","method":"Gdap1 knockout mouse, embryonic motor neuron cultures, Ca2+ imaging, electron microscopy, electrophysiology, immunofluorescence","journal":"PLoS genetics","confidence":"High","confidence_rationale":"Tier 2 — in vivo model with multiple orthogonal mechanistic readouts","pmids":["25860513"],"is_preprint":false},{"year":2011,"finding":"GDAP1 complements G2/M cell cycle delay in yeast fis1Δ cells. GDAP1 interacts with β-tubulin (TUBB in human, Tub2p in yeast), and CMT-causing missense mutations rescue fis1Δ mitochondrial phenotypes but not the cell cycle delay, suggesting GDAP1 links mitochondria to the microtubule cytoskeleton.","method":"Yeast complementation assay, cell cycle analysis, co-immunoprecipitation of GDAP1 with β-tubulin in yeast and human cells, CMT mutant analysis","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 — reciprocal co-IP plus genetic epistasis in yeast with CMT mutant dissection","pmids":["21890626"],"is_preprint":false},{"year":2016,"finding":"GDAP1 exhibits theta-class-like glutathione S-transferase (GST) activity in vitro using recombinant protein. This activity is regulated in an autoinhibitory manner by the C-terminal hydrophobic domain 1 (HD1). The amphipathic pattern of HD1 is also required for GDAP1 to induce membrane dynamics/fission, suggesting a molecular switch between pro-fission active and auto-inhibited inactive conformations.","method":"In vitro GST enzymatic assay with recombinant GDAP1, HD1 domain mutagenesis, membrane dynamics assay","journal":"Scientific reports","confidence":"High","confidence_rationale":"Tier 1 — first in vitro demonstration of enzymatic activity with mutagenesis defining autoinhibitory mechanism","pmids":["27841286"],"is_preprint":false},{"year":2017,"finding":"Loss-of-function recessive GDAP1 mutations (in the α-loop) reduce SOCE and blunt Ca2+-dependent upregulation of mitochondrial respiration, while dominant mutations do not. MCU silencing or mitochondrial depolarization mimics the SOCE defect, indicating that mitochondrial Ca2+ uptake is required for normal SOCE-stimulated respiration.","method":"siRNA knockdown, MCU silencing, mitochondrial depolarization, Ca2+ imaging, oxygen consumption rate measurement (Seahorse)","journal":"Scientific reports","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods with mechanistic dissection of recessive vs. dominant mutations","pmids":["28220846"],"is_preprint":false},{"year":2014,"finding":"Junctophilin-1 (JPH1) can rescue SOCE activity in GDAP1-silenced cells. JPH1 colocalizes with STIM1 (SOCE activator) at ER-plasma membrane puncta in a GDAP1-dependent manner. The combination of GDAP1(p.R120W) and JPH1(p.R213P) dramatically reduces SOCE activity, establishing JPH1 as a genetic modifier of GDAP1-related CMT acting in the same Ca2+ homeostasis pathway.","method":"siRNA rescue experiments, co-localization imaging, Ca2+ imaging, genetic epistasis in patient cohort","journal":"Human molecular genetics","confidence":"High","confidence_rationale":"Tier 2 — functional rescue, co-localization, and Ca2+ measurements with genetic epistasis","pmids":["25168384"],"is_preprint":false},{"year":2021,"finding":"GDAP1 participates in basal autophagy and interacts with PIKfyve kinase (a lysosomal regulator) and with LAMP-1, establishing GDAP1-LAMP-1 as a new tethering pair for mitochondria-lysosome membrane contact sites (MCSs). GDAP1 deficiency causes giant lysosomes, delays autophagic lysosome reformation, and reduces mitochondria-lysosome MCSs.","method":"Co-immunoprecipitation (GDAP1-LAMP-1, GDAP1-PIKfyve), live-cell imaging of MCSs, autophagy flux assays, GSH rescue experiments","journal":"Human molecular genetics","confidence":"High","confidence_rationale":"Tier 2 — reciprocal Co-IP for interaction partners with functional consequence validation and rescue experiments","pmids":["33372681"],"is_preprint":false},{"year":2022,"finding":"GDAP1 interacts with the actin-depolymerizing protein Cofilin-1 and beta-tubulin in a redox-dependent manner. GDAP1 loss reduces F-actin near mitochondria, restricts mitochondrial localization of the fission factor Drp1, causing tubular mitochondria. GDAP1 loss also disrupts mitochondria-ER contact sites and lowers mitochondrial Ca2+ levels, inhibiting the pyruvate dehydrogenase complex (PDC) and causing metabolic shift to glutamine dependence.","method":"Co-immunoprecipitation (GDAP1-Cofilin-1, GDAP1-tubulin), F-actin staining, Drp1 localization, Seahorse metabolic assay, Ca2+ imaging, patient-derived motoneurons and SH-SY5Y knockdown","journal":"Communications biology","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods identifying a mechanistic chain from actin signaling to metabolic dysfunction","pmids":["35662277"],"is_preprint":false},{"year":2020,"finding":"GDAP1 has lost the ability to bind glutathione (G-site critical residues are altered) while retaining substrate-binding activity at the H-site (α-loop is primary determinant). GDAP1 overexpression produces a mitochondrial fragmentation phenotype distinct from oxidative-stress-induced fragmentation, dependent on the transmembrane domain and a unique hydrophobic domain absent in canonical GSTs.","method":"Biochemical binding assays with recombinant GDAP1, structural analysis, mutagenesis of G-site and α-loop, overexpression in HeLa cells with mitochondrial morphology readout","journal":"FASEB journal","confidence":"High","confidence_rationale":"Tier 1-2 — biochemical reconstitution with mutagenesis and structural analysis","pmids":["32274853"],"is_preprint":false},{"year":2021,"finding":"Crystal structure of the complete human GDAP1 core domain reveals a novel dimerization mode within the GST family. The long GDAP1-specific insertion forms an extended helix and flexible loop. GDAP1 is catalytically inactive toward classical GST substrates. A ligand (fatty acid hexadecanedioic acid) was identified binding near CMT-linked residues, increasing protein stability and inducing conformational and oligomerization changes, suggesting allosteric regulation.","method":"X-ray crystallography, metabolite screening, thermal stability assay, oligomerization analysis","journal":"Frontiers in molecular biosciences","confidence":"High","confidence_rationale":"Tier 1 — crystal structure with ligand identification and functional biochemical validation","pmids":["33585569"],"is_preprint":false},{"year":2009,"finding":"YY1 transcription factor directly regulates human GDAP1 gene expression. A consensus YY1 binding site in the GDAP1 core promoter is functional in vitro and in living cells; YY1 overexpression activates the GDAP1 promoter and increases endogenous mRNA, while YY1 knockdown decreases GDAP1 expression.","method":"Promoter-reporter assay, in vitro binding assay, RNAi knockdown of YY1 in HEK293 cells, YY1 overexpression","journal":"Genomics","confidence":"Medium","confidence_rationale":"Tier 2 — multiple methods (reporter, in vitro binding, RNAi) in single study","pmids":["19720140"],"is_preprint":false},{"year":2023,"finding":"Using synchrotron radiation oriented circular dichroism and SAXS, GDAP1 is shown to be anchored in the mitochondrial outer membrane via a single transmembrane helix flanked by two peripheral helices that interact with opposite leaflets of the outer mitochondrial membrane. This provides the first experimental structural model for full-length GDAP1 membrane assembly.","method":"Oriented circular dichroism spectroscopy with synchrotron radiation, small-angle X-ray scattering, peptide studies in lipidic environment","journal":"Biophysical chemistry","confidence":"Medium","confidence_rationale":"Tier 1 — biophysical structural analysis with novel experimental models, single study","pmids":["37778197"],"is_preprint":false},{"year":2021,"finding":"Loss of GDAP1 in Gdap1-/- embryonic motor neurons causes defective mitochondrial axonal transport, reduced ATP production, deteriorated bioenergetic status, and increased axonal calcium levels both basally and after glutamate stimulation. Glutamate-stimulated respiration is blunted, linking GDAP1-dependent mitochondrial function directly to calcium homeostasis in axons.","method":"Gdap1 knockout mouse embryonic motor neuron cultures, live-cell mitochondrial transport imaging, ATP bioluminescence assay, Ca2+ imaging, Seahorse respirometry","journal":"Neurobiology of disease","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal in vitro and ex vivo methods in genetically defined model","pmids":["33582224"],"is_preprint":false},{"year":2014,"finding":"Drosophila Gdap1 ortholog alters mitochondrial size, morphology and distribution when up- or downregulated in a tissue-specific manner, causing neuronal and muscular degeneration. Muscular degeneration is tissue-autonomous and not dependent on innervation. Metabolic analyses indicate alterations in oxidative stress are a long-term consequence, not a primary cause, of the mitochondrial dysfunction.","method":"Tissue-specific Drosophila Gdap1 overexpression and RNAi knockdown, mitochondrial morphology analysis, neuromuscular degeneration scoring, metabolic profiling","journal":"Human molecular genetics","confidence":"Medium","confidence_rationale":"Tier 2 — in vivo Drosophila model with tissue-specific manipulation and multiple readouts; ortholog","pmids":["25122658"],"is_preprint":false},{"year":2022,"finding":"Crystal structures of CMT-linked GDAP1 variants (H123R, R120W, R120Q, A247V, R282H) reveal that disease mutations decrease protein thermal stability without major structural disruption. A side-chain interaction network between helices α3, α6, and α7 and a hinge in helix α6 are identified as structurally critical regions affected by CMT mutations.","method":"X-ray crystallography of disease variants, thermal stability assays, solution behavior analysis","journal":"FEBS open bio","confidence":"High","confidence_rationale":"Tier 1 — crystal structures of multiple disease variants with biochemical characterization","pmids":["35509130"],"is_preprint":false},{"year":2021,"finding":"GDAP1 mutations influence structure and function of the trans-Golgi network (TGN). Some CMT-causing mutations reduce GDAP1 protein expression and cause selective disruption of Golgi apparatus structure and function in yeast and human cell models.","method":"Yeast and human cell expression models, Golgi morphology analysis, functional Golgi assays","journal":"International journal of molecular sciences","confidence":"Medium","confidence_rationale":"Tier 3 — novel finding in two model systems but single study with limited mechanistic depth","pmids":["33477664"],"is_preprint":false},{"year":2023,"finding":"Dominant GDAP1 variant p.Thr157Pro increases mitochondria-lysosome MCSs correlating with hyper-fissioned mitochondrial network, while recessive variant p.Arg161His decreases these contacts and causes elongated mitochondria. These opposite effects on MCSs support GDAP1's role in regulating Ca2+ transfer from lysosomes to mitochondria.","method":"High-resolution live-cell imaging of mitochondria-lysosome contacts, mitochondrial network morphology analysis, comparison of dominant vs. recessive variants","journal":"Biology open","confidence":"Medium","confidence_rationale":"Tier 2 — direct quantitative imaging with mechanistic interpretation, single study","pmids":["36912213"],"is_preprint":false},{"year":2024,"finding":"GDAP1 acts as a tether of mitochondria-peroxisome membrane contact sites (MCSs), maintaining peroxisomal number and integrity. GDAP1 deficiency disrupts these MCSs causing peroxisomal abnormalities reversible by PPARγ activation or glutathione supplementation. GDAP1 also regulates the redox state at mitochondria-lysosome contacts. In Gdap1-/- sciatic nerve, nodes of Ranvier are disrupted with abnormal distribution of mitochondria, lysosomes, and peroxisomes.","method":"High-resolution microscopy, live-cell imaging with pH-sensitive probes, transcriptomics, lipidomics, Gdap1-/- mouse model, patient-derived fibroblasts, pharmacological rescue","journal":"Research square (preprint)","confidence":"Medium","confidence_rationale":"Tier 2 — multiple orthogonal methods in vivo and in vitro, but preprint","pmids":["39801517"],"is_preprint":true}],"current_model":"GDAP1 is a tail-anchored outer mitochondrial membrane protein with GST-like domain architecture that functions as a mitochondrial (and peroxisomal) fission factor dependent on Drp1 and Fis1/Mff; it regulates mitochondrial morphology and axonal transport, maintains mitochondrial membrane contact sites with the ER, lysosomes, and peroxisomes, controls store-operated Ca2+ entry and Ca2+-stimulated respiration, interacts with Cofilin-1 and β-tubulin in a redox-dependent manner to control F-actin near mitochondria, and possesses theta-class-like GST activity regulated autoinhibitorily by its C-terminal hydrophobic domain 1, with CMT-causing mutations disrupting these functions through reduced fission activity (recessive) or impaired fusion/increased ROS (dominant)."},"narrative":{"teleology":[{"year":2003,"claim":"Sequence analysis established that GDAP1 belongs to a novel GST-related protein family, providing the structural framework for understanding its enzymatic and non-enzymatic functions.","evidence":"Comparative genomics and domain prediction identifying GST-like domains and unique C-terminal transmembrane regions","pmids":["14595091"],"confidence":"Medium","gaps":["No experimental verification of enzymatic activity at this stage","3D structure not determined","Functional significance of GST-like domain unknown"]},{"year":2005,"claim":"Direct localization experiments resolved that GDAP1 resides on the mitochondrial outer membrane and that overexpression fragments mitochondria, establishing it as a candidate fission factor.","evidence":"Transient overexpression in COS-7 cells with organelle marker co-localization, subcellular fractionation, and C-terminal deletion analysis","pmids":["15772096"],"confidence":"High","gaps":["Mechanism of fission induction unknown","Dependence on canonical fission machinery not tested","Endogenous protein behavior not characterized"]},{"year":2009,"claim":"Genetic epistasis demonstrated that GDAP1-mediated fission requires Drp1 and Fis1, and revealed a genotype-mechanism correlation where recessive CMT mutations reduce fission while dominant mutations impair fusion and elevate ROS.","evidence":"Overexpression/knockdown with epistasis to Drp1/Fis1, ROS measurement, and apoptosis assays; plus tail-anchor topology mapping by mutagenesis","pmids":["19782751","19340293"],"confidence":"High","gaps":["Direct physical interaction with Drp1/Fis1 not demonstrated","How dominant mutations impair fusion mechanistically unclear","In vivo validation lacking"]},{"year":2011,"claim":"Two parallel advances linked GDAP1 to glutathione metabolism and the cytoskeleton: GDAP1 increases cellular GSH and protects against oxidative stress, while it physically interacts with β-tubulin and complements yeast fis1Δ cell-cycle defects.","evidence":"GSH quantification with overexpression/knockdown in neuronal lines and patient fibroblasts; yeast complementation with co-immunoprecipitation of GDAP1–β-tubulin","pmids":["21965300","21890626"],"confidence":"High","gaps":["Whether GSH increase reflects direct enzymatic activity or indirect effect unknown","Physiological relevance of tubulin interaction in neurons not tested"]},{"year":2013,"claim":"GDAP1 was shown to regulate inter-organelle communication: its loss disrupts mitochondria–ER contacts and store-operated Ca²⁺ entry, and it additionally promotes Drp1/Mff-dependent peroxisomal fission via Pex19-mediated dual targeting.","evidence":"siRNA knockdown with Ca²⁺ imaging and ER–mitochondria contact quantification in SH-SY5Y cells; immunofluorescence co-localization with peroxisomal markers and epistasis with Mff","pmids":["23542510","23628762"],"confidence":"High","gaps":["Molecular mechanism of ER–mitochondria tethering not identified","Whether peroxisomal and mitochondrial fission roles are independent or coordinated unknown"]},{"year":2014,"claim":"In vivo studies in Gdap1 knockout mice and Drosophila confirmed that GDAP1 loss causes enlarged mitochondria, impaired axonal transport, and cell-autonomous Schwann cell pathology, while JPH1 was identified as a genetic modifier acting through SOCE.","evidence":"Gdap1 constitutive and conditional knockout mice with live-cell transport imaging and morphological analysis; Drosophila tissue-specific RNAi; JPH1 rescue of SOCE in GDAP1-silenced cells with patient genetic epistasis","pmids":["24480485","25122658","25168384"],"confidence":"High","gaps":["Molecular basis of GDAP1 role in Schwann cell myelination unclear","Whether JPH1–STIM1 interaction requires direct GDAP1 binding unresolved"]},{"year":2015,"claim":"Gdap1 knockout motor neurons revealed a comprehensive phenotype—reduced SOCE, ER cisternae changes, decreased α-tubulin acetylation, and increased autophagy—establishing GDAP1 as a nexus for mitochondria–ER interaction and cytoskeletal integrity.","evidence":"Gdap1 knockout mouse embryonic motor neuron cultures with Ca²⁺ imaging, electron microscopy, and immunofluorescence","pmids":["25860513"],"confidence":"High","gaps":["Causal hierarchy among cytoskeletal, ER, and mitochondrial phenotypes not resolved","Direct tubulin acetylation mechanism unknown"]},{"year":2016,"claim":"Biochemical reconstitution demonstrated that GDAP1 possesses theta-class-like GST enzymatic activity autoinhibited by HD1, linking HD1 integrity to both enzymatic and fission functions through a conformational switch.","evidence":"In vitro GST assay with recombinant GDAP1 and HD1 domain mutagenesis","pmids":["27841286"],"confidence":"High","gaps":["Physiological substrate of GST activity not identified","Whether enzymatic activity is required for fission in vivo unresolved"]},{"year":2017,"claim":"Mechanistic dissection showed that recessive α-loop mutations specifically impair Ca²⁺-dependent upregulation of mitochondrial respiration through reduced SOCE, linking GDAP1 to mitochondrial Ca²⁺ uptake via MCU.","evidence":"siRNA knockdown, MCU silencing, mitochondrial depolarization, and Seahorse respirometry with recessive vs. dominant mutation comparison","pmids":["28220846"],"confidence":"High","gaps":["Whether GDAP1 directly interacts with MCU pathway components unknown","Neuron-type specificity of this metabolic defect not explored"]},{"year":2020,"claim":"Refined biochemical analysis showed that GDAP1 has lost the canonical glutathione-binding G-site while retaining substrate binding at the H-site (α-loop), and that its fission-promoting activity is mechanistically distinct from oxidative-stress-induced fragmentation.","evidence":"Recombinant GDAP1 binding assays, G-site and α-loop mutagenesis, mitochondrial morphology in HeLa cells","pmids":["32274853"],"confidence":"High","gaps":["Identity of endogenous H-site substrates/ligands in cells unknown","Relationship between H-site occupancy and fission activity not tested in vivo"]},{"year":2021,"claim":"Structural and functional studies converged: the crystal structure revealed a novel GST-family dimer with a long insertion helix and fatty acid ligand binding near CMT residues, while cell biology showed GDAP1 tethers mitochondria to lysosomes via LAMP-1 interaction and regulates autophagy and axonal bioenergetics.","evidence":"X-ray crystallography with metabolite screening; Co-IP of GDAP1–LAMP-1/PIKfyve with autophagy flux assays; Gdap1 KO motor neuron ATP/Ca²⁺/transport measurements","pmids":["33585569","33372681","33582224"],"confidence":"High","gaps":["Physiological relevance of fatty acid ligand binding not confirmed in cells","Whether LAMP-1 tethering is direct or mediated by intermediary proteins in vivo unclear"]},{"year":2022,"claim":"The mechanistic chain from GDAP1 to fission was completed: GDAP1 interacts with Cofilin-1 in a redox-dependent manner to maintain perimiochondrial F-actin required for Drp1 recruitment, and its loss shifts metabolism to glutamine dependence via reduced mitochondrial Ca²⁺ and PDC inhibition. Crystal structures of five CMT variants showed destabilization without gross structural changes.","evidence":"Co-IP of GDAP1–Cofilin-1, F-actin and Drp1 localization imaging, Seahorse metabolomics in patient-derived motoneurons; X-ray crystallography and thermal stability of disease variants","pmids":["35662277","35509130"],"confidence":"High","gaps":["Whether GDAP1 enzymatically modifies Cofilin-1 or acts as a scaffold unknown","How reduced protein stability translates to dominant vs. recessive disease phenotypes not fully explained"]},{"year":2023,"claim":"Biophysical characterization provided the first experimental model of how GDAP1 is anchored in the outer mitochondrial membrane, with peripheral helices interacting with both leaflets flanking a single transmembrane helix, and live-cell imaging showed that dominant and recessive variants have opposite effects on mitochondria–lysosome contacts.","evidence":"Synchrotron radiation circular dichroism and SAXS of membrane-associated GDAP1 peptides; quantitative live-cell imaging of mitochondria–lysosome MCSs with dominant (T157P) vs. recessive (R161H) variants","pmids":["37778197","36912213"],"confidence":"Medium","gaps":["Full-length membrane-embedded structure not yet resolved at atomic level","Direction of Ca²⁺ transfer at mitochondria–lysosome contacts not directly measured"]},{"year":null,"claim":"Key open questions include the identity of endogenous GDAP1 substrates/ligands, how its GST-like enzymatic activity is coupled to fission or tethering functions, the structural basis of full-length membrane-embedded GDAP1 in organelle contact sites, and how dominant versus recessive mutations produce opposite effects on organelle dynamics despite similarly destabilizing the protein.","evidence":"","pmids":[],"confidence":"High","gaps":["Endogenous substrate/ligand of H-site not identified","Full-length cryo-EM or crystal structure in membrane context absent","Mechanism distinguishing dominant from recessive pathogenesis at the molecular level remains incomplete"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016740","term_label":"transferase activity","supporting_discovery_ids":[11,16]},{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[10,15]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[14,15]}],"localization":[{"term_id":"GO:0005739","term_label":"mitochondrion","supporting_discovery_ids":[0,2,8,9,17,19]},{"term_id":"GO:0005777","term_label":"peroxisome","supporting_discovery_ids":[5,25]},{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[13]}],"pathway":[{"term_id":"R-HSA-1852241","term_label":"Organelle biogenesis and maintenance","supporting_discovery_ids":[0,1,5,8,9]},{"term_id":"R-HSA-9612973","term_label":"Autophagy","supporting_discovery_ids":[9,14]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[4,12,13]},{"term_id":"R-HSA-1643685","term_label":"Disease","supporting_discovery_ids":[1,8,22]}],"complexes":[],"partners":["DRP1","FIS1","MFF","LAMP1","CFL1","TUBB","JPH1","PIKFYVE"],"other_free_text":[]},"mechanistic_narrative":"GDAP1 is a tail-anchored outer mitochondrial membrane protein that functions as a fission factor for both mitochondria and peroxisomes, coordinating organelle dynamics with cytoskeletal organization, inter-organelle membrane contact sites, and calcium homeostasis in neurons and Schwann cells. It promotes Drp1/Fis1/Mff-dependent fission and maintains mitochondria–ER, mitochondria–lysosome (via LAMP-1 tethering), and mitochondria–peroxisome contact sites; its loss impairs store-operated Ca²⁺ entry, Ca²⁺-stimulated mitochondrial respiration, axonal mitochondrial transport, and autophagic lysosome reformation [PMID:19782751, PMID:23542510, PMID:33372681, PMID:33582224]. GDAP1 contains a GST-like fold with a novel dimerization mode and possesses theta-class-like GST activity autoinhibited by its C-terminal hydrophobic domain 1 (HD1), though it has lost classical glutathione-binding capacity; it interacts with Cofilin-1 and β-tubulin in a redox-dependent manner to maintain perimiochondrial F-actin required for Drp1 recruitment [PMID:27841286, PMID:33585569, PMID:32274853, PMID:35662277]. Biallelic loss-of-function mutations cause autosomal recessive Charcot–Marie–Tooth disease (CMT4A) through reduced fission and impaired calcium signaling, whereas dominant mutations interfere with fusion and increase ROS, and CMT-linked variants destabilize the protein without major structural disruption [PMID:19782751, PMID:35509130, PMID:25860513]."},"prefetch_data":{"uniprot":{"accession":"Q8TB36","full_name":"Ganglioside-induced differentiation-associated protein 1","aliases":[],"length_aa":358,"mass_kda":41.3,"function":"Regulates the mitochondrial network by promoting mitochondrial fission","subcellular_location":"Mitochondrion outer membrane; Cytoplasm","url":"https://www.uniprot.org/uniprotkb/Q8TB36/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/GDAP1","classification":"Not 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Cells Harboring a Nonsense Mutation in GDAP1 Gene.","date":"2023","source":"Pharmaceuticals (Basel, Switzerland)","url":"https://pubmed.ncbi.nlm.nih.gov/37513945","citation_count":8,"is_preprint":false},{"pmid":"32438208","id":"PMC_32438208","title":"Cigarette smoke exposure has region-specific effects on GDAP1 expression in mouse hippocampus.","date":"2020","source":"Psychiatry research","url":"https://pubmed.ncbi.nlm.nih.gov/32438208","citation_count":7,"is_preprint":false},{"pmid":"18492089","id":"PMC_18492089","title":"A novel mutation in the GDAP1 gene is associated with autosomal recessive Charcot-Marie-Tooth disease in an Amish family.","date":"2008","source":"Clinical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/18492089","citation_count":7,"is_preprint":false},{"pmid":"19381883","id":"PMC_19381883","title":"Novel GDAP1 mutation in a Turkish family with CMT2K (CMT2K with novel GDAP1 mutation).","date":"2009","source":"Neuromolecular medicine","url":"https://pubmed.ncbi.nlm.nih.gov/19381883","citation_count":7,"is_preprint":false},{"pmid":"18991200","id":"PMC_18991200","title":"Clinical, electrophysiological and genetic studies of two families with mutations in the GDAP1 gene.","date":"2008","source":"Neuropediatrics","url":"https://pubmed.ncbi.nlm.nih.gov/18991200","citation_count":7,"is_preprint":false},{"pmid":"32897397","id":"PMC_32897397","title":"Deep geno- and phenotyping in two consanguineous families with CMT2 reveals HADHA as an unusual disease-causing gene and an intronic variant in GDAP1 as an unusual mutation.","date":"2020","source":"Journal of neurology","url":"https://pubmed.ncbi.nlm.nih.gov/32897397","citation_count":7,"is_preprint":false},{"pmid":"28236508","id":"PMC_28236508","title":"Phenotypical features of a new dominant GDAP1 pathogenic variant (p.R226del) in axonal Charcot-Marie-Tooth disease.","date":"2017","source":"Neuromuscular disorders : NMD","url":"https://pubmed.ncbi.nlm.nih.gov/28236508","citation_count":6,"is_preprint":false},{"pmid":"33136338","id":"PMC_33136338","title":"Identification and functional characterization of novel GDAP1 variants in Chinese patients with Charcot-Marie-Tooth disease.","date":"2020","source":"Annals of clinical and translational neurology","url":"https://pubmed.ncbi.nlm.nih.gov/33136338","citation_count":6,"is_preprint":false},{"pmid":"33903021","id":"PMC_33903021","title":"GDAP1 mutations are frequent among Brazilian patients with autosomal recessive axonal Charcot-Marie-Tooth disease.","date":"2021","source":"Neuromuscular disorders : NMD","url":"https://pubmed.ncbi.nlm.nih.gov/33903021","citation_count":6,"is_preprint":false},{"pmid":"29396836","id":"PMC_29396836","title":"WES homozygosity mapping in a recessive form of Charcot-Marie-Tooth neuropathy reveals intronic GDAP1 variant leading to a premature stop codon.","date":"2018","source":"Neurogenetics","url":"https://pubmed.ncbi.nlm.nih.gov/29396836","citation_count":6,"is_preprint":false},{"pmid":"35509130","id":"PMC_35509130","title":"Structural insights into Charcot-Marie-Tooth disease-linked mutations in human GDAP1.","date":"2022","source":"FEBS open bio","url":"https://pubmed.ncbi.nlm.nih.gov/35509130","citation_count":5,"is_preprint":false},{"pmid":"37058526","id":"PMC_37058526","title":"Conserved intramolecular networks in GDAP1 are closely connected to CMT-linked mutations and protein stability.","date":"2023","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/37058526","citation_count":5,"is_preprint":false},{"pmid":"28395795","id":"PMC_28395795","title":"Generation of a disease-specific iPS cell line derived from a patient with Charcot-Marie-Tooth type 2K lacking functional GDAP1 gene.","date":"2016","source":"Stem cell 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Colombia)","url":"https://pubmed.ncbi.nlm.nih.gov/26848201","citation_count":3,"is_preprint":false},{"pmid":"34632054","id":"PMC_34632054","title":"Phenotype of Patients With Charcot-Marie-Tooth With the p.His123Arg Mutation in GDAP1 in Northern Finland.","date":"2021","source":"Neurology. Genetics","url":"https://pubmed.ncbi.nlm.nih.gov/34632054","citation_count":3,"is_preprint":false},{"pmid":"39801517","id":"PMC_39801517","title":"Abnormal redox balance at membrane contact sites causes axonopathy in GDAP1-related Charcot-Marie-Tooth disease.","date":"2024","source":"Research square","url":"https://pubmed.ncbi.nlm.nih.gov/39801517","citation_count":2,"is_preprint":false},{"pmid":"36353131","id":"PMC_36353131","title":"Autosomal dominant GDAP1 mutation with severe phenotype and respiratory involvement: A case report.","date":"2022","source":"Frontiers in neurology","url":"https://pubmed.ncbi.nlm.nih.gov/36353131","citation_count":2,"is_preprint":false},{"pmid":"40004086","id":"PMC_40004086","title":"GDAP1 Is Dysregulated at DNA Methylation and H3K4me3 Levels in Alcohol Use Disorder.","date":"2025","source":"International journal of molecular sciences","url":"https://pubmed.ncbi.nlm.nih.gov/40004086","citation_count":2,"is_preprint":false},{"pmid":"37778197","id":"PMC_37778197","title":"Conformational analysis of membrane-proximal segments of GDAP1 in a lipidic environment using synchrotron radiation suggests a mode of assembly at the mitochondrial outer membrane.","date":"2023","source":"Biophysical chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/37778197","citation_count":2,"is_preprint":false},{"pmid":"40588830","id":"PMC_40588830","title":"Digenesis in Charcot-Marie-Tooth Disease: Impact of Combined Mutations in the MFN2 and GDAP1 Genes.","date":"2025","source":"Journal of the peripheral nervous system : JPNS","url":"https://pubmed.ncbi.nlm.nih.gov/40588830","citation_count":2,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":46593,"output_tokens":6135,"usd":0.115902},"stage2":{"model":"claude-opus-4-6","input_tokens":9779,"output_tokens":3660,"usd":0.210592},"total_usd":0.326494,"stage1_batch_id":"msgbatch_01DzrsgVgYngY1hvM3DU1yF2","stage2_batch_id":"msgbatch_01KA9b7iRzKFdhoBUT7vCvSe","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2005,\n      \"finding\": \"GDAP1 localizes to the mitochondrial outer membrane, with C-terminal transmembrane domains necessary for correct mitochondrial targeting. Overexpression of GDAP1 induces mitochondrial fragmentation, suggesting a role in the fission pathway of mitochondrial network dynamics.\",\n      \"method\": \"Transient overexpression, co-localization with organelle markers in COS-7 cells, western blot of subcellular fractions, C-terminal domain deletion analysis\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — direct localization experiment with functional consequence, replicated across multiple methods and cell lines\",\n      \"pmids\": [\"15772096\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"GDAP1 is a mitochondrial fission factor whose activity is dependent on the fission factors Drp1 and Fis1. Recessively inherited CMT mutations reduce fission activity, while dominantly inherited mutations interfere with mitochondrial fusion and increase ROS production and apoptosis susceptibility.\",\n      \"method\": \"GDAP1 overexpression and knockdown in cells, mitochondrial morphology assays, ROS measurement, apoptosis assays, epistasis with Drp1 and Fis1\",\n      \"journal\": \"Neurobiology of disease\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods including KD/OE with defined phenotypic readouts and genetic epistasis\",\n      \"pmids\": [\"19782751\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"GDAP1 is a tail-anchored mitochondrial outer membrane protein. A single transmembrane domain (TMD) together with adjacent basic amino acids is critical for MOM targeting. Basic amino acids bordering the TMD in the cytoplasm are required for both targeting and GDAP1-mediated fission function.\",\n      \"method\": \"Domain mutagenesis, subcellular fractionation, mitochondrial morphology assays, deletion and chimeric constructs\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — systematic mutagenesis with functional validation of targeting and fission activity\",\n      \"pmids\": [\"19340293\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"GDAP1 protein shows sequence similarity to glutathione S-transferases (GSTs) and contains an extended region in GST domain II absent in most GSTs, plus C-terminal transmembrane domains. GDAP1 and its paralogue GDAP1L1 define a novel class of GST-related genes.\",\n      \"method\": \"Comparative genomics, sequence analysis, structural domain prediction\",\n      \"journal\": \"Molecular biology and evolution\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 4 — computational/comparative genomics analysis, but foundational for understanding domain architecture\",\n      \"pmids\": [\"14595091\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"GDAP1 silencing causes abnormal mitochondrial distribution, reduces mitochondrial-ER contacts, and decreases store-operated Ca2+ entry (SOCE) following ER-Ca2+ mobilization. GDAP1 interacts with vesicle-organelle trafficking proteins RAB6B and caytaxin, suggesting a role in mitochondrial movement.\",\n      \"method\": \"siRNA knockdown in SH-SY5Y cells, co-immunoprecipitation, Ca2+ imaging, mitochondrial distribution analysis, ER-mitochondria contact site quantification\",\n      \"journal\": \"Neurobiology of disease\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods including Co-IP for interaction partners and functional Ca2+ measurements with defined cellular phenotype\",\n      \"pmids\": [\"23542510\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"GDAP1 localizes to peroxisomes in addition to mitochondria, mediated by the import receptor Pex19. GDAP1 knockdown causes peroxisomal elongation rescued by re-expression. GDAP1-induced peroxisomal fission depends on integrity of hydrophobic domain 1 (HD1) and on Drp1 and Mff, similar to mitochondrial fission.\",\n      \"method\": \"Immunofluorescence co-localization, siRNA knockdown, rescue experiments with wild-type and CMT mutant GDAP1, epistasis with Drp1 and Mff\",\n      \"journal\": \"EMBO reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods with functional rescue experiments and genetic epistasis\",\n      \"pmids\": [\"23628762\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"GDAP1 overexpression increases total cellular glutathione (GSH) content and mitochondrial membrane potential. GDAP1 knockdown increases susceptibility to GSH depletion. CMT-causing recessive mutations with reduced fission activity fail to increase GSH, linking GDAP1's potential GST activity to oxidative stress protection.\",\n      \"method\": \"Overexpression and siRNA knockdown in neuronal cell lines (HT22, NSC34), glutathione measurement, mitochondrial membrane potential assay, analysis of CMT patient fibroblasts\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods in multiple cell types including patient-derived cells\",\n      \"pmids\": [\"21965300\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"GDAP1L1, the paralogue of GDAP1 expressed in the CNS, responds to elevated oxidized glutathione by translocating from the cytosol to mitochondria and inserting into the mitochondrial outer membrane, compensating for GDAP1 loss in the CNS of Gdap1 knockout mice.\",\n      \"method\": \"Gdap1 knockout mouse model, subcellular fractionation, western blot, comparison of CNS vs PNS\",\n      \"journal\": \"Brain : a journal of neurology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — in vivo knockout model with biochemical validation of GDAP1L1 translocation mechanism\",\n      \"pmids\": [\"24480485\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"In Gdap1 knockout mice, intra-axonal mitochondria of peripheral neurons are larger and mitochondrial transport is impaired in cultured sensory neurons. Loss of Gdap1 in Schwann cells recapitulates hypomyelinating peripheral neuropathy, demonstrating cell-autonomous function in Schwann cells.\",\n      \"method\": \"Gdap1 conditional and constitutive knockout mice, live-cell mitochondrial transport imaging, morphological analysis\",\n      \"journal\": \"Brain : a journal of neurology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — in vivo knockout model with direct live-cell imaging and cell-type-specific phenotypic analysis\",\n      \"pmids\": [\"24480485\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"Loss of GDAP1 in knockout mice results in large and defective mitochondria in motor neurons, changes in ER cisternae, reduced cytoskeletal α-tubulin acetylation, increased autophagy, reduced cytosolic calcium, and reduced SOCE response, consistent with impaired mitochondria-ER interaction.\",\n      \"method\": \"Gdap1 knockout mouse, embryonic motor neuron cultures, Ca2+ imaging, electron microscopy, electrophysiology, immunofluorescence\",\n      \"journal\": \"PLoS genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — in vivo model with multiple orthogonal mechanistic readouts\",\n      \"pmids\": [\"25860513\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"GDAP1 complements G2/M cell cycle delay in yeast fis1Δ cells. GDAP1 interacts with β-tubulin (TUBB in human, Tub2p in yeast), and CMT-causing missense mutations rescue fis1Δ mitochondrial phenotypes but not the cell cycle delay, suggesting GDAP1 links mitochondria to the microtubule cytoskeleton.\",\n      \"method\": \"Yeast complementation assay, cell cycle analysis, co-immunoprecipitation of GDAP1 with β-tubulin in yeast and human cells, CMT mutant analysis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal co-IP plus genetic epistasis in yeast with CMT mutant dissection\",\n      \"pmids\": [\"21890626\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"GDAP1 exhibits theta-class-like glutathione S-transferase (GST) activity in vitro using recombinant protein. This activity is regulated in an autoinhibitory manner by the C-terminal hydrophobic domain 1 (HD1). The amphipathic pattern of HD1 is also required for GDAP1 to induce membrane dynamics/fission, suggesting a molecular switch between pro-fission active and auto-inhibited inactive conformations.\",\n      \"method\": \"In vitro GST enzymatic assay with recombinant GDAP1, HD1 domain mutagenesis, membrane dynamics assay\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — first in vitro demonstration of enzymatic activity with mutagenesis defining autoinhibitory mechanism\",\n      \"pmids\": [\"27841286\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Loss-of-function recessive GDAP1 mutations (in the α-loop) reduce SOCE and blunt Ca2+-dependent upregulation of mitochondrial respiration, while dominant mutations do not. MCU silencing or mitochondrial depolarization mimics the SOCE defect, indicating that mitochondrial Ca2+ uptake is required for normal SOCE-stimulated respiration.\",\n      \"method\": \"siRNA knockdown, MCU silencing, mitochondrial depolarization, Ca2+ imaging, oxygen consumption rate measurement (Seahorse)\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods with mechanistic dissection of recessive vs. dominant mutations\",\n      \"pmids\": [\"28220846\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Junctophilin-1 (JPH1) can rescue SOCE activity in GDAP1-silenced cells. JPH1 colocalizes with STIM1 (SOCE activator) at ER-plasma membrane puncta in a GDAP1-dependent manner. The combination of GDAP1(p.R120W) and JPH1(p.R213P) dramatically reduces SOCE activity, establishing JPH1 as a genetic modifier of GDAP1-related CMT acting in the same Ca2+ homeostasis pathway.\",\n      \"method\": \"siRNA rescue experiments, co-localization imaging, Ca2+ imaging, genetic epistasis in patient cohort\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — functional rescue, co-localization, and Ca2+ measurements with genetic epistasis\",\n      \"pmids\": [\"25168384\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"GDAP1 participates in basal autophagy and interacts with PIKfyve kinase (a lysosomal regulator) and with LAMP-1, establishing GDAP1-LAMP-1 as a new tethering pair for mitochondria-lysosome membrane contact sites (MCSs). GDAP1 deficiency causes giant lysosomes, delays autophagic lysosome reformation, and reduces mitochondria-lysosome MCSs.\",\n      \"method\": \"Co-immunoprecipitation (GDAP1-LAMP-1, GDAP1-PIKfyve), live-cell imaging of MCSs, autophagy flux assays, GSH rescue experiments\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal Co-IP for interaction partners with functional consequence validation and rescue experiments\",\n      \"pmids\": [\"33372681\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"GDAP1 interacts with the actin-depolymerizing protein Cofilin-1 and beta-tubulin in a redox-dependent manner. GDAP1 loss reduces F-actin near mitochondria, restricts mitochondrial localization of the fission factor Drp1, causing tubular mitochondria. GDAP1 loss also disrupts mitochondria-ER contact sites and lowers mitochondrial Ca2+ levels, inhibiting the pyruvate dehydrogenase complex (PDC) and causing metabolic shift to glutamine dependence.\",\n      \"method\": \"Co-immunoprecipitation (GDAP1-Cofilin-1, GDAP1-tubulin), F-actin staining, Drp1 localization, Seahorse metabolic assay, Ca2+ imaging, patient-derived motoneurons and SH-SY5Y knockdown\",\n      \"journal\": \"Communications biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods identifying a mechanistic chain from actin signaling to metabolic dysfunction\",\n      \"pmids\": [\"35662277\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"GDAP1 has lost the ability to bind glutathione (G-site critical residues are altered) while retaining substrate-binding activity at the H-site (α-loop is primary determinant). GDAP1 overexpression produces a mitochondrial fragmentation phenotype distinct from oxidative-stress-induced fragmentation, dependent on the transmembrane domain and a unique hydrophobic domain absent in canonical GSTs.\",\n      \"method\": \"Biochemical binding assays with recombinant GDAP1, structural analysis, mutagenesis of G-site and α-loop, overexpression in HeLa cells with mitochondrial morphology readout\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — biochemical reconstitution with mutagenesis and structural analysis\",\n      \"pmids\": [\"32274853\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"Crystal structure of the complete human GDAP1 core domain reveals a novel dimerization mode within the GST family. The long GDAP1-specific insertion forms an extended helix and flexible loop. GDAP1 is catalytically inactive toward classical GST substrates. A ligand (fatty acid hexadecanedioic acid) was identified binding near CMT-linked residues, increasing protein stability and inducing conformational and oligomerization changes, suggesting allosteric regulation.\",\n      \"method\": \"X-ray crystallography, metabolite screening, thermal stability assay, oligomerization analysis\",\n      \"journal\": \"Frontiers in molecular biosciences\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — crystal structure with ligand identification and functional biochemical validation\",\n      \"pmids\": [\"33585569\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"YY1 transcription factor directly regulates human GDAP1 gene expression. A consensus YY1 binding site in the GDAP1 core promoter is functional in vitro and in living cells; YY1 overexpression activates the GDAP1 promoter and increases endogenous mRNA, while YY1 knockdown decreases GDAP1 expression.\",\n      \"method\": \"Promoter-reporter assay, in vitro binding assay, RNAi knockdown of YY1 in HEK293 cells, YY1 overexpression\",\n      \"journal\": \"Genomics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — multiple methods (reporter, in vitro binding, RNAi) in single study\",\n      \"pmids\": [\"19720140\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Using synchrotron radiation oriented circular dichroism and SAXS, GDAP1 is shown to be anchored in the mitochondrial outer membrane via a single transmembrane helix flanked by two peripheral helices that interact with opposite leaflets of the outer mitochondrial membrane. This provides the first experimental structural model for full-length GDAP1 membrane assembly.\",\n      \"method\": \"Oriented circular dichroism spectroscopy with synchrotron radiation, small-angle X-ray scattering, peptide studies in lipidic environment\",\n      \"journal\": \"Biophysical chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 — biophysical structural analysis with novel experimental models, single study\",\n      \"pmids\": [\"37778197\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"Loss of GDAP1 in Gdap1-/- embryonic motor neurons causes defective mitochondrial axonal transport, reduced ATP production, deteriorated bioenergetic status, and increased axonal calcium levels both basally and after glutamate stimulation. Glutamate-stimulated respiration is blunted, linking GDAP1-dependent mitochondrial function directly to calcium homeostasis in axons.\",\n      \"method\": \"Gdap1 knockout mouse embryonic motor neuron cultures, live-cell mitochondrial transport imaging, ATP bioluminescence assay, Ca2+ imaging, Seahorse respirometry\",\n      \"journal\": \"Neurobiology of disease\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal in vitro and ex vivo methods in genetically defined model\",\n      \"pmids\": [\"33582224\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Drosophila Gdap1 ortholog alters mitochondrial size, morphology and distribution when up- or downregulated in a tissue-specific manner, causing neuronal and muscular degeneration. Muscular degeneration is tissue-autonomous and not dependent on innervation. Metabolic analyses indicate alterations in oxidative stress are a long-term consequence, not a primary cause, of the mitochondrial dysfunction.\",\n      \"method\": \"Tissue-specific Drosophila Gdap1 overexpression and RNAi knockdown, mitochondrial morphology analysis, neuromuscular degeneration scoring, metabolic profiling\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — in vivo Drosophila model with tissue-specific manipulation and multiple readouts; ortholog\",\n      \"pmids\": [\"25122658\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Crystal structures of CMT-linked GDAP1 variants (H123R, R120W, R120Q, A247V, R282H) reveal that disease mutations decrease protein thermal stability without major structural disruption. A side-chain interaction network between helices α3, α6, and α7 and a hinge in helix α6 are identified as structurally critical regions affected by CMT mutations.\",\n      \"method\": \"X-ray crystallography of disease variants, thermal stability assays, solution behavior analysis\",\n      \"journal\": \"FEBS open bio\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — crystal structures of multiple disease variants with biochemical characterization\",\n      \"pmids\": [\"35509130\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"GDAP1 mutations influence structure and function of the trans-Golgi network (TGN). Some CMT-causing mutations reduce GDAP1 protein expression and cause selective disruption of Golgi apparatus structure and function in yeast and human cell models.\",\n      \"method\": \"Yeast and human cell expression models, Golgi morphology analysis, functional Golgi assays\",\n      \"journal\": \"International journal of molecular sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 — novel finding in two model systems but single study with limited mechanistic depth\",\n      \"pmids\": [\"33477664\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Dominant GDAP1 variant p.Thr157Pro increases mitochondria-lysosome MCSs correlating with hyper-fissioned mitochondrial network, while recessive variant p.Arg161His decreases these contacts and causes elongated mitochondria. These opposite effects on MCSs support GDAP1's role in regulating Ca2+ transfer from lysosomes to mitochondria.\",\n      \"method\": \"High-resolution live-cell imaging of mitochondria-lysosome contacts, mitochondrial network morphology analysis, comparison of dominant vs. recessive variants\",\n      \"journal\": \"Biology open\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — direct quantitative imaging with mechanistic interpretation, single study\",\n      \"pmids\": [\"36912213\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"GDAP1 acts as a tether of mitochondria-peroxisome membrane contact sites (MCSs), maintaining peroxisomal number and integrity. GDAP1 deficiency disrupts these MCSs causing peroxisomal abnormalities reversible by PPARγ activation or glutathione supplementation. GDAP1 also regulates the redox state at mitochondria-lysosome contacts. In Gdap1-/- sciatic nerve, nodes of Ranvier are disrupted with abnormal distribution of mitochondria, lysosomes, and peroxisomes.\",\n      \"method\": \"High-resolution microscopy, live-cell imaging with pH-sensitive probes, transcriptomics, lipidomics, Gdap1-/- mouse model, patient-derived fibroblasts, pharmacological rescue\",\n      \"journal\": \"Research square (preprint)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods in vivo and in vitro, but preprint\",\n      \"pmids\": [\"39801517\"],\n      \"is_preprint\": true\n    }\n  ],\n  \"current_model\": \"GDAP1 is a tail-anchored outer mitochondrial membrane protein with GST-like domain architecture that functions as a mitochondrial (and peroxisomal) fission factor dependent on Drp1 and Fis1/Mff; it regulates mitochondrial morphology and axonal transport, maintains mitochondrial membrane contact sites with the ER, lysosomes, and peroxisomes, controls store-operated Ca2+ entry and Ca2+-stimulated respiration, interacts with Cofilin-1 and β-tubulin in a redox-dependent manner to control F-actin near mitochondria, and possesses theta-class-like GST activity regulated autoinhibitorily by its C-terminal hydrophobic domain 1, with CMT-causing mutations disrupting these functions through reduced fission activity (recessive) or impaired fusion/increased ROS (dominant).\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"GDAP1 is a tail-anchored outer mitochondrial membrane protein that functions as a fission factor for both mitochondria and peroxisomes, coordinating organelle dynamics with cytoskeletal organization, inter-organelle membrane contact sites, and calcium homeostasis in neurons and Schwann cells. It promotes Drp1/Fis1/Mff-dependent fission and maintains mitochondria–ER, mitochondria–lysosome (via LAMP-1 tethering), and mitochondria–peroxisome contact sites; its loss impairs store-operated Ca²⁺ entry, Ca²⁺-stimulated mitochondrial respiration, axonal mitochondrial transport, and autophagic lysosome reformation [PMID:19782751, PMID:23542510, PMID:33372681, PMID:33582224]. GDAP1 contains a GST-like fold with a novel dimerization mode and possesses theta-class-like GST activity autoinhibited by its C-terminal hydrophobic domain 1 (HD1), though it has lost classical glutathione-binding capacity; it interacts with Cofilin-1 and β-tubulin in a redox-dependent manner to maintain perimiochondrial F-actin required for Drp1 recruitment [PMID:27841286, PMID:33585569, PMID:32274853, PMID:35662277]. Biallelic loss-of-function mutations cause autosomal recessive Charcot–Marie–Tooth disease (CMT4A) through reduced fission and impaired calcium signaling, whereas dominant mutations interfere with fusion and increase ROS, and CMT-linked variants destabilize the protein without major structural disruption [PMID:19782751, PMID:35509130, PMID:25860513].\",\n  \"teleology\": [\n    {\n      \"year\": 2003,\n      \"claim\": \"Sequence analysis established that GDAP1 belongs to a novel GST-related protein family, providing the structural framework for understanding its enzymatic and non-enzymatic functions.\",\n      \"evidence\": \"Comparative genomics and domain prediction identifying GST-like domains and unique C-terminal transmembrane regions\",\n      \"pmids\": [\"14595091\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No experimental verification of enzymatic activity at this stage\", \"3D structure not determined\", \"Functional significance of GST-like domain unknown\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Direct localization experiments resolved that GDAP1 resides on the mitochondrial outer membrane and that overexpression fragments mitochondria, establishing it as a candidate fission factor.\",\n      \"evidence\": \"Transient overexpression in COS-7 cells with organelle marker co-localization, subcellular fractionation, and C-terminal deletion analysis\",\n      \"pmids\": [\"15772096\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of fission induction unknown\", \"Dependence on canonical fission machinery not tested\", \"Endogenous protein behavior not characterized\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Genetic epistasis demonstrated that GDAP1-mediated fission requires Drp1 and Fis1, and revealed a genotype-mechanism correlation where recessive CMT mutations reduce fission while dominant mutations impair fusion and elevate ROS.\",\n      \"evidence\": \"Overexpression/knockdown with epistasis to Drp1/Fis1, ROS measurement, and apoptosis assays; plus tail-anchor topology mapping by mutagenesis\",\n      \"pmids\": [\"19782751\", \"19340293\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct physical interaction with Drp1/Fis1 not demonstrated\", \"How dominant mutations impair fusion mechanistically unclear\", \"In vivo validation lacking\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Two parallel advances linked GDAP1 to glutathione metabolism and the cytoskeleton: GDAP1 increases cellular GSH and protects against oxidative stress, while it physically interacts with β-tubulin and complements yeast fis1Δ cell-cycle defects.\",\n      \"evidence\": \"GSH quantification with overexpression/knockdown in neuronal lines and patient fibroblasts; yeast complementation with co-immunoprecipitation of GDAP1–β-tubulin\",\n      \"pmids\": [\"21965300\", \"21890626\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether GSH increase reflects direct enzymatic activity or indirect effect unknown\", \"Physiological relevance of tubulin interaction in neurons not tested\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"GDAP1 was shown to regulate inter-organelle communication: its loss disrupts mitochondria–ER contacts and store-operated Ca²⁺ entry, and it additionally promotes Drp1/Mff-dependent peroxisomal fission via Pex19-mediated dual targeting.\",\n      \"evidence\": \"siRNA knockdown with Ca²⁺ imaging and ER–mitochondria contact quantification in SH-SY5Y cells; immunofluorescence co-localization with peroxisomal markers and epistasis with Mff\",\n      \"pmids\": [\"23542510\", \"23628762\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular mechanism of ER–mitochondria tethering not identified\", \"Whether peroxisomal and mitochondrial fission roles are independent or coordinated unknown\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"In vivo studies in Gdap1 knockout mice and Drosophila confirmed that GDAP1 loss causes enlarged mitochondria, impaired axonal transport, and cell-autonomous Schwann cell pathology, while JPH1 was identified as a genetic modifier acting through SOCE.\",\n      \"evidence\": \"Gdap1 constitutive and conditional knockout mice with live-cell transport imaging and morphological analysis; Drosophila tissue-specific RNAi; JPH1 rescue of SOCE in GDAP1-silenced cells with patient genetic epistasis\",\n      \"pmids\": [\"24480485\", \"25122658\", \"25168384\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular basis of GDAP1 role in Schwann cell myelination unclear\", \"Whether JPH1–STIM1 interaction requires direct GDAP1 binding unresolved\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Gdap1 knockout motor neurons revealed a comprehensive phenotype—reduced SOCE, ER cisternae changes, decreased α-tubulin acetylation, and increased autophagy—establishing GDAP1 as a nexus for mitochondria–ER interaction and cytoskeletal integrity.\",\n      \"evidence\": \"Gdap1 knockout mouse embryonic motor neuron cultures with Ca²⁺ imaging, electron microscopy, and immunofluorescence\",\n      \"pmids\": [\"25860513\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Causal hierarchy among cytoskeletal, ER, and mitochondrial phenotypes not resolved\", \"Direct tubulin acetylation mechanism unknown\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Biochemical reconstitution demonstrated that GDAP1 possesses theta-class-like GST enzymatic activity autoinhibited by HD1, linking HD1 integrity to both enzymatic and fission functions through a conformational switch.\",\n      \"evidence\": \"In vitro GST assay with recombinant GDAP1 and HD1 domain mutagenesis\",\n      \"pmids\": [\"27841286\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological substrate of GST activity not identified\", \"Whether enzymatic activity is required for fission in vivo unresolved\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Mechanistic dissection showed that recessive α-loop mutations specifically impair Ca²⁺-dependent upregulation of mitochondrial respiration through reduced SOCE, linking GDAP1 to mitochondrial Ca²⁺ uptake via MCU.\",\n      \"evidence\": \"siRNA knockdown, MCU silencing, mitochondrial depolarization, and Seahorse respirometry with recessive vs. dominant mutation comparison\",\n      \"pmids\": [\"28220846\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether GDAP1 directly interacts with MCU pathway components unknown\", \"Neuron-type specificity of this metabolic defect not explored\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Refined biochemical analysis showed that GDAP1 has lost the canonical glutathione-binding G-site while retaining substrate binding at the H-site (α-loop), and that its fission-promoting activity is mechanistically distinct from oxidative-stress-induced fragmentation.\",\n      \"evidence\": \"Recombinant GDAP1 binding assays, G-site and α-loop mutagenesis, mitochondrial morphology in HeLa cells\",\n      \"pmids\": [\"32274853\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Identity of endogenous H-site substrates/ligands in cells unknown\", \"Relationship between H-site occupancy and fission activity not tested in vivo\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Structural and functional studies converged: the crystal structure revealed a novel GST-family dimer with a long insertion helix and fatty acid ligand binding near CMT residues, while cell biology showed GDAP1 tethers mitochondria to lysosomes via LAMP-1 interaction and regulates autophagy and axonal bioenergetics.\",\n      \"evidence\": \"X-ray crystallography with metabolite screening; Co-IP of GDAP1–LAMP-1/PIKfyve with autophagy flux assays; Gdap1 KO motor neuron ATP/Ca²⁺/transport measurements\",\n      \"pmids\": [\"33585569\", \"33372681\", \"33582224\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological relevance of fatty acid ligand binding not confirmed in cells\", \"Whether LAMP-1 tethering is direct or mediated by intermediary proteins in vivo unclear\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"The mechanistic chain from GDAP1 to fission was completed: GDAP1 interacts with Cofilin-1 in a redox-dependent manner to maintain perimiochondrial F-actin required for Drp1 recruitment, and its loss shifts metabolism to glutamine dependence via reduced mitochondrial Ca²⁺ and PDC inhibition. Crystal structures of five CMT variants showed destabilization without gross structural changes.\",\n      \"evidence\": \"Co-IP of GDAP1–Cofilin-1, F-actin and Drp1 localization imaging, Seahorse metabolomics in patient-derived motoneurons; X-ray crystallography and thermal stability of disease variants\",\n      \"pmids\": [\"35662277\", \"35509130\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether GDAP1 enzymatically modifies Cofilin-1 or acts as a scaffold unknown\", \"How reduced protein stability translates to dominant vs. recessive disease phenotypes not fully explained\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Biophysical characterization provided the first experimental model of how GDAP1 is anchored in the outer mitochondrial membrane, with peripheral helices interacting with both leaflets flanking a single transmembrane helix, and live-cell imaging showed that dominant and recessive variants have opposite effects on mitochondria–lysosome contacts.\",\n      \"evidence\": \"Synchrotron radiation circular dichroism and SAXS of membrane-associated GDAP1 peptides; quantitative live-cell imaging of mitochondria–lysosome MCSs with dominant (T157P) vs. recessive (R161H) variants\",\n      \"pmids\": [\"37778197\", \"36912213\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Full-length membrane-embedded structure not yet resolved at atomic level\", \"Direction of Ca²⁺ transfer at mitochondria–lysosome contacts not directly measured\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"Key open questions include the identity of endogenous GDAP1 substrates/ligands, how its GST-like enzymatic activity is coupled to fission or tethering functions, the structural basis of full-length membrane-embedded GDAP1 in organelle contact sites, and how dominant versus recessive mutations produce opposite effects on organelle dynamics despite similarly destabilizing the protein.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Endogenous substrate/ligand of H-site not identified\", \"Full-length cryo-EM or crystal structure in membrane context absent\", \"Mechanism distinguishing dominant from recessive pathogenesis at the molecular level remains incomplete\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016740\", \"supporting_discovery_ids\": [11, 16]},\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [10, 15]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [14, 15]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [0, 2, 8, 9, 17, 19]},\n      {\"term_id\": \"GO:0005777\", \"supporting_discovery_ids\": [5, 25]},\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [13]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1852241\", \"supporting_discovery_ids\": [0, 1, 5, 8, 9]},\n      {\"term_id\": \"R-HSA-9612973\", \"supporting_discovery_ids\": [9, 14]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [4, 12, 13]},\n      {\"term_id\": \"R-HSA-1643685\", \"supporting_discovery_ids\": [1, 8, 22]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\n      \"DRP1\",\n      \"FIS1\",\n      \"MFF\",\n      \"LAMP1\",\n      \"CFL1\",\n      \"TUBB\",\n      \"JPH1\",\n      \"PIKFYVE\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}