{"gene":"AGTPBP1","run_date":"2026-06-09T22:02:42","timeline":{"discoveries":[{"year":2002,"finding":"Nna1 (AGTPBP1) was identified as the gene mutated in the Purkinje cell degeneration (pcd) mouse, encoding a putative nuclear protein with a zinc carboxypeptidase domain; loss-of-function of Nna1 causes degeneration of cerebellar Purkinje neurons, retinal photoreceptors, olfactory bulb mitral neurons, selected thalamic neurons, and defective spermatogenesis.","method":"Genetic mapping and sequencing of pcd alleles; identification of mutations in Nna1 in original pcd, pcd2J, and pcd3J alleles","journal":"Science","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic identification of causal mutations in multiple independent alleles, replicated across alleles","pmids":["11884758"],"is_preprint":false},{"year":2000,"finding":"Nna1 encodes a zinc carboxypeptidase with nuclear localization signals and an ATP/GTP binding motif; GFP-Nna1 fusion protein localizes to both cytoplasmic and nuclear compartments in cultured neurons.","method":"GFP-fusion protein transfection and live-cell imaging in cultured neurons; bioinformatic domain analysis","journal":"Molecular and cellular neurosciences","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — direct localization experiment with GFP fusion, single lab, consistent with subsequent studies","pmids":["11083920"],"is_preprint":false},{"year":2006,"finding":"The carboxypeptidase substrate-binding site of Nna1 is functionally essential for Purkinje cell survival; a substrate-binding site mutant of Nna1 failed to rescue ataxic behavior and Purkinje cell loss in pcd(3J) mice, whereas wild-type Nna1 did rescue.","method":"Transgenic rescue in pcd mice using L7/pcp2 promoter-driven wild-type vs. substrate-binding site mutant Nna1; behavioral and histological analysis","journal":"Molecular and cellular neurosciences","confidence":"High","confidence_rationale":"Tier 2 / Strong — transgenic rescue with mutagenesis, in vivo functional validation, clear positive vs. negative control","pmids":["16952463"],"is_preprint":false},{"year":2006,"finding":"The pcd5J allele results from a single aspartic acid insertion at position 775 of Nna1, which does not affect mRNA expression but dramatically destabilizes the Nna1 protein, as shown by pulse-chase experiments.","method":"Sequencing of Nna1 in pcd5J mice; pulse-chase protein stability assay","journal":"Mammalian genome","confidence":"High","confidence_rationale":"Tier 1 / Moderate — pulse-chase biochemical assay directly measuring protein stability, single lab with orthogonal sequencing","pmids":["16465590"],"is_preprint":false},{"year":2007,"finding":"Nna1-like proteins constitute a new M14 subfamily (M14D) of metallocarboxypeptidases with an unusually open active site; a C. elegans ortholog was shown to be a fully functional metallocarboxypeptidase cleaving C-terminal amino acids from synthetic peptides, with activity activated by ATP/ADP and preferentially inhibited by Z-Glu-Tyr, resembling tubulin carboxypeptidase activity.","method":"Recombinant protein expression and in vitro enzymatic assay with synthetic peptide substrates; phylogenetic and conformational modeling","journal":"FASEB journal","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution of enzymatic activity with substrate specificity profiling, functional inhibitor characterization","pmids":["17244817"],"is_preprint":false},{"year":2008,"finding":"The zinc-binding domain of Nna1 is required to prevent retinal photoreceptor loss and Purkinje cell degeneration; a BAC transgene containing wild-type Nna1 rescues these phenotypes in pcd(5J) mice, but mutation of the zinc-binding domain abolishes rescue.","method":"BAC transgenic rescue in pcd(5J) mice with wild-type vs. zinc-binding domain mutant Nna1; histological analysis of retina and cerebellum","journal":"Vision research","confidence":"High","confidence_rationale":"Tier 2 / Strong — in vivo transgenic rescue with domain-inactivating mutagenesis, clear functional validation","pmids":["18602413"],"is_preprint":false},{"year":2010,"finding":"CCP1/Nna1 (AGTPBP1) functions in protein turnover by degrading proteasome-generated peptides into amino acids; pcd mice lacking functional CCP1/Nna1 accumulate hundreds of intracellular peptides from cytosolic and mitochondrial proteins, while proteasome activity is normal, indicating a specific downstream peptide-degradation deficit.","method":"Quantitative proteomics and peptidomics comparing pcd mutant vs. wild-type mouse brain regions; 2D gel electrophoresis; proteasome activity assay; autophagy markers","journal":"FASEB journal","confidence":"High","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal biochemical methods (peptidomics, proteomics, enzyme activity assay), single lab","pmids":["20061535"],"is_preprint":false},{"year":2010,"finding":"Loss of CCP1/Nna1 causes elevated autophagy in both degenerating and non-degenerating brain regions of pcd mice, proposed to result from decreased cellular amino acid levels due to failure to degrade proteasome-generated peptides.","method":"Autophagy marker analysis in pcd mouse brain regions","journal":"Autophagy","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — loss-of-function cellular phenotype with defined marker readout, supported by parallel peptidomics study from same lab","pmids":["20484972"],"is_preprint":false},{"year":2010,"finding":"Mutant Nna1 leads to abnormal Purkinje cell dendrite development through increased intranuclear localization of lysyl oxidase propeptide, which interferes with NF-κB RelA signaling and microtubule-associated protein regulation of microtubule stability.","method":"Single-cell gene profiling of pcd(Sid) mouse Purkinje cells; virus-based gene transfer rescue; pathway analysis of NF-κB RelA signaling and MAP-microtubule stability","journal":"Neuron","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — viral rescue experiment with pathway analysis, single lab, multiple downstream readouts","pmids":["20920790"],"is_preprint":false},{"year":2010,"finding":"AGTPBP1 is expressed in spermatogenic cells between late-stage primary spermatocytes and round spermatids; loss of Agtpbp1 in pcd(3J) mice causes apoptosis of differentiating germ cells beginning at the pachytene spermatocyte stage, with altered expression of cyclin B3 and deubiquitinating enzymes USP2 and USP9y.","method":"Immunohistochemistry with anti-AGTPBP1 antibody in testes; global gene expression analysis of pcd(3J) testes; histological and apoptosis analysis","journal":"Molecules and cells","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct localization by IHC tied to functional loss-of-function phenotype and gene expression changes, single lab","pmids":["21110128"],"is_preprint":false},{"year":2012,"finding":"Recombinant Nna1 is a monomeric metallocarboxypeptidase that removes glutamate from tubulin and preferentially cleaves substrates with 2 or more C-terminal glutamate residues (Vmax for 3 glutamates ~7-fold higher than 2 glutamates); catalytic mutants D1007E, R1078E, and E1094A are inactive; ATP/GTP binding is not required for catalysis or neuronal survival in vivo.","method":"Purified recombinant Nna1 enzymatic assay with synthetic substrates and tubulin; active-site mutagenesis; transgenic rescue in pcd mice","journal":"FASEB journal","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro reconstitution with defined substrates, mutagenesis of catalytic residues, orthogonal in vivo transgenic validation","pmids":["22835831"],"is_preprint":false},{"year":2012,"finding":"A missense mutation c.2909G>C (p.Arg970Pro) in the AGTPBP1 gene, affecting a conserved residue for catalytic activity, causes autosomal recessive lower motor neuron disease in Romney sheep, establishing that AGTPBP1 loss-of-function causes motor neuron disease in a large mammal.","method":"Genome-wide homozygosity mapping; sequencing of candidate gene AGTPBP1; genotyping in affected, carrier, and normal sheep","journal":"Heredity","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic mapping and variant identification with 100% phenotype concordance, no in vitro functional assay","pmids":["22588130"],"is_preprint":false},{"year":2018,"finding":"Conditional knockout of the carboxypeptidase domain of Nna1 in mice produces Purkinje cell degeneration with cerebellar ataxia and results in increased polyglutamylated tubulin in the cerebellum, confirming that Nna1 acts as a de-glutamatase on the C-terminus of α- and β-tubulin; ER stress marker CHOP is upregulated in mutant Purkinje cells.","method":"Conditional Cre-loxP knockout of exons encoding carboxypeptidase domain; western blot for polyglutamylated tubulin; ER stress markers; histology","journal":"Journal of neurochemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean conditional KO with defined molecular readout (tubulin glutamylation), multiple orthogonal analyses","pmids":["30225910"],"is_preprint":false},{"year":2020,"finding":"Loss of Nna1 deglutamylase activity leads to hyperglutamylated microtubules and dimeric tubulins accumulating in Purkinje neurons; treatment with a microtubule depolymerizer corrects the glutamylation/deglutamylation ratio and increases Purkinje neuron survival; pcd Purkinje neurons also display ER stress, unfolded protein response, and protein synthesis inhibition preceding death by apoptosis/necroptosis.","method":"Laser capture microdissection of single Purkinje neurons; mRNA and protein analysis; pharmacological treatment with microtubule depolymerizer; ER stress marker analysis","journal":"JCI insight","confidence":"High","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods (single-cell analysis, pharmacological rescue, ER stress markers) in single study","pmids":["33004692"],"is_preprint":false},{"year":2015,"finding":"agtpbp1 is essential for T lymphocyte development in zebrafish; homozygous agtpbp1 mutants and morpholino knockdown embryos show impaired T cell development at 6 days of age.","method":"Gene-breaking transposon mutagenesis; flow cytometry of immune cells; morpholino knockdown confirmation","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic mutant plus morpholino knockdown confirmation, defined cellular phenotype, single lab","pmids":["26161877"],"is_preprint":false},{"year":2022,"finding":"The N-terminal nuclear localization signal (NLS) of Nna1 is involved in hippocampal function; exon 3 (N-terminal NLS) knockout mice that still express a truncated Nna1 protein do not develop the pcd phenotype but show reduced GluA2 AMPA receptor and kinesin-1 in the hippocampal synaptosomal fraction, along with impaired context- and cue-dependent learning and altered anxiety.","method":"Conditional exon 3 knockout mouse; behavioral tests (elevated plus maze, light/dark box, fear conditioning); synaptosomal fractionation and western blot for GluA2 and kinesin-1","journal":"International journal of molecular sciences","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean KO with defined molecular readout (synaptosomal GluA2, kinesin-1) and behavioral phenotype, single lab","pmids":["36361749"],"is_preprint":false},{"year":2023,"finding":"AGTPBP1 is localized to the manchette structure in murine spermatids, and its loss (null mice) causes sperm head and tail defects associated with abnormal polyglutamylated tubulin accumulation and decreased Δ-2 tubulin; in humans, AGTPBP1 missense mutations produce teratozoospermia with sperm head and flagella defects and fragmented/abnormal AGTPBP1 localization in the neck and annulus regions.","method":"Immunolocalization in mouse testes; analysis of Agtpbp1-null mouse sperm morphology; western blot for polyglutamylated and Δ-2 tubulin; whole-exome sequencing in human patients","journal":"Journal of cellular and molecular medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct localization plus null mouse phenotype with molecular tubulin modification readout, supported by human genetic data","pmids":["37937809"],"is_preprint":false},{"year":2025,"finding":"AGTPBP1 knockout leads to excessive neurite outgrowth, increased CRMP2 expression, mitochondrial dysfunction, and a hyperdopaminergic state in differentiated neurons in vitro; in zebrafish, AGTPBP1 knockdown causes reduced brain volume and impaired motor function; lacosamide (a CRMP2 modulator) rescues these defects.","method":"AGTPBP1 KO cell model; zebrafish knockdown; neurite outgrowth measurement; CRMP2 western blot; mitochondrial function assay; dopamine level measurement; pharmacological rescue with lacosamide","journal":"Molecular neurobiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal in vitro and in vivo methods, single lab, pharmacological rescue","pmids":["40347376"],"is_preprint":false},{"year":2025,"finding":"The R791H knock-in mutation in Agtpbp1 (equivalent to human R811H) causes sperm head and tail defects with abnormal accumulation of polyglutamylated tubulin in the sperm head, confirming that the carboxypeptidase activity of AGTPBP1 is required for proper sperm morphology.","method":"CRISPR knock-in mouse model; sperm morphological analysis; immunofluorescence for polyglutamylated tubulin","journal":"Journal of assisted reproduction and genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — knock-in murine model with defined molecular readout, single lab, orthogonal morphological and molecular analyses","pmids":["41160201"],"is_preprint":false},{"year":2025,"finding":"Nna1 overexpression in Müller cells suppresses microtubule hyper-glutamylation, reducing autophagy and apoptosis in vitro and ameliorating diabetic retinopathy progression in vivo.","method":"In vivo knockdown and overexpression of Nna1 in diabetic mouse retina; in vitro Müller cell experiments; measurement of autophagy and apoptosis markers; polyglutamylation assay","journal":"Advanced science","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo and in vitro gain- and loss-of-function with defined molecular readout (tubulin glutamylation, autophagy), single lab","pmids":["41190783"],"is_preprint":false},{"year":2026,"finding":"AGTPBP1 promotes pancreatic cancer cell proliferation and migration through activation of the MAPK/ERK pathway (increased ERK1/2 phosphorylation) and upregulation of MYLK at the transcriptional level; ERK signaling controls MYLK activity post-translationally without affecting MYLK expression.","method":"Gain-of-function and siRNA knockdown in PANC-1/AsPC-1 cells; ERK inhibitor (PD98059) rescue experiments; western blot; RNA-seq; IHC","journal":"Tissue & cell","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, cell-line based, no in vitro biochemical reconstitution, mechanism inferred from pharmacological inhibition","pmids":["41930881"],"is_preprint":false},{"year":2026,"finding":"AGTPBP1 promotes breast cancer progression by repressing envoplakin (EVPL) expression, leading to ERK1/2 activation; rescue experiments confirmed that EVPL overexpression attenuates AGTPBP1-induced malignant phenotypes and ERK activation.","method":"Stable overexpression and knockdown in T47D and MDA-MB-231 cells; RNA-sequencing; rescue experiments with EVPL overexpression; western blot for ERK phosphorylation","journal":"Experimental cell research","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, cell-line based, no biochemical reconstitution, mechanism inferred from RNA-seq and rescue","pmids":["41905574"],"is_preprint":false}],"current_model":"AGTPBP1/Nna1 is a monomeric M14D-subfamily metallocarboxypeptidase (cytosolic carboxypeptidase 1, CCP1) that removes C-terminal glutamate residues from polyglutamylated substrates—most notably α- and β-tubulin—using a catalytically essential zinc-binding domain; loss of this deglutamylase activity causes hyperglutamylation of microtubules, ER stress, disrupted protein turnover downstream of the proteasome, and consequent degeneration of cerebellar Purkinje cells, retinal photoreceptors, olfactory mitral neurons, and motor neurons, as well as defective spermatogenesis, while its N-terminal nuclear localization domain has additional roles in hippocampal synaptic receptor trafficking."},"narrative":{"mechanistic_narrative":"AGTPBP1/Nna1 (cytosolic carboxypeptidase 1, CCP1) is a monomeric zinc metallocarboxypeptidase of the M14D subfamily that removes C-terminal glutamate residues from polyglutamylated substrates, most notably α- and β-tubulin, with a preference for substrates carrying two or more terminal glutamates [PMID:17244817, PMID:22835831, PMID:30225910]. Its catalytic activity depends on an intact zinc-binding and substrate-binding active site, and active-site or zinc-domain mutations abolish both enzymatic function and the ability to rescue neurodegeneration in vivo [PMID:16952463, PMID:18602413, PMID:22835831]. Loss of this deglutamylase activity produces hyperglutamylated, destabilized microtubules and triggers ER stress, the unfolded protein response, and protein-synthesis inhibition that precede neuronal death, a degenerative cascade pharmacologically reversible by microtubule depolymerization [PMID:30225910, PMID:33004692]. AGTPBP1 was originally identified as the gene mutated in the Purkinje cell degeneration (pcd) mouse, where loss of function causes degeneration of cerebellar Purkinje neurons, retinal photoreceptors, olfactory mitral neurons, and selected thalamic neurons, together with defective spermatogenesis [PMID:11884758]; recessive loss-of-function variants further cause motor neuron disease in sheep and teratozoospermia in humans, where AGTPBP1 localizes to the spermatid manchette and its catalytic activity is required for normal sperm head and tail morphology [PMID:22588130, PMID:37937809, PMID:41160201]. Beyond tubulin deglutamylation, AGTPBP1 contributes to downstream protein turnover by degrading proteasome-generated peptides into amino acids, and its loss elevates autophagy [PMID:20061535, PMID:20484972]. A distinct N-terminal nuclear-localization domain, separable from catalytic function, supports hippocampal synaptic trafficking of the GluA2 AMPA receptor and kinesin-1 [PMID:36361749].","teleology":[{"year":2000,"claim":"Established the domain architecture and dual nuclear/cytoplasmic localization of Nna1, framing it as a carboxypeptidase with regulatory nucleotide-binding and nuclear-targeting features.","evidence":"GFP-fusion live imaging in cultured neurons plus bioinformatic domain analysis","pmids":["11083920"],"confidence":"Medium","gaps":["Localization from overexpressed GFP fusion only","Did not test enzymatic activity or substrate"]},{"year":2002,"claim":"Identified Nna1 as the gene causally mutated in the pcd mouse, linking its loss to a defined multi-tissue degenerative phenotype before any biochemical function was known.","evidence":"Genetic mapping and sequencing of multiple independent pcd alleles","pmids":["11884758"],"confidence":"High","gaps":["Did not define molecular substrate or catalytic mechanism","Causal cell-biological lesion unknown"]},{"year":2006,"claim":"Demonstrated that the carboxypeptidase substrate-binding site is functionally required in vivo, showing the degenerative phenotype reflects loss of enzymatic activity rather than a structural role.","evidence":"Transgenic rescue of pcd mice with wild-type vs. substrate-binding-site mutant Nna1","pmids":["16952463"],"confidence":"High","gaps":["Endogenous substrate not yet identified","Did not localize where catalysis acts"]},{"year":2006,"claim":"Showed a single-residue insertion (pcd5J) destabilizes the protein without affecting mRNA, establishing protein stability as a route to functional loss.","evidence":"Sequencing plus pulse-chase protein stability assay","pmids":["16465590"],"confidence":"High","gaps":["Mechanism of destabilization not defined","Did not test residual activity of mutant"]},{"year":2007,"claim":"Provided the first direct enzymatic evidence by reconstituting metallocarboxypeptidase activity from a Nna1 ortholog, defining the M14D subfamily and a tubulin-carboxypeptidase-like specificity.","evidence":"Recombinant C. elegans ortholog in vitro assay with synthetic peptides and inhibitor profiling","pmids":["17244817"],"confidence":"High","gaps":["Used ortholog rather than mammalian protein","Tubulin substrate not directly demonstrated here"]},{"year":2008,"claim":"Confirmed the zinc-binding domain is essential in vivo, tying the catalytic metal center to prevention of photoreceptor and Purkinje cell loss.","evidence":"BAC transgenic rescue of pcd5J with wild-type vs. zinc-domain mutant Nna1","pmids":["18602413"],"confidence":"High","gaps":["Did not measure substrate modification in rescued tissue"]},{"year":2010,"claim":"Linked AGTPBP1 to bulk protein turnover by showing pcd mice accumulate proteasome-generated peptides with normal proteasome activity, and that resulting amino acid scarcity elevates autophagy.","evidence":"Peptidomics/proteomics, proteasome activity assays, and autophagy markers in pcd mouse brain","pmids":["20061535","20484972"],"confidence":"High","gaps":["Did not establish whether peptide accumulation is a direct catalytic deficit or secondary","Relationship to tubulin deglutamylation unresolved at this stage"]},{"year":2010,"claim":"Identified downstream signaling consequences of Nna1 loss in Purkinje dendrite development through intranuclear lysyl oxidase propeptide affecting NF-κB RelA and MAP-microtubule stability.","evidence":"Single-cell profiling and viral rescue in pcd Purkinje cells with pathway analysis","pmids":["20920790"],"confidence":"Medium","gaps":["Causal chain from carboxypeptidase loss to lysyl oxidase indirect","Single lab pathway inference"]},{"year":2010,"claim":"Connected AGTPBP1 to spermatogenesis, defining its germ-cell expression window and the apoptotic stage of germ-cell loss upon its mutation.","evidence":"IHC and gene-expression analysis in pcd3J testes","pmids":["21110128"],"confidence":"Medium","gaps":["Did not link to tubulin modification mechanism","Gene-expression changes correlative"]},{"year":2012,"claim":"Definitively reconstituted mammalian Nna1 as a monomeric deglutamylase removing glutamate from tubulin with chain-length preference, identified catalytic residues, and showed ATP/GTP binding is dispensable for catalysis and neuronal survival.","evidence":"Purified recombinant Nna1 assays with tubulin/synthetic substrates, active-site mutagenesis, transgenic rescue","pmids":["22835831"],"confidence":"High","gaps":["Did not address in vivo glutamylation balance directly","Function of the nucleotide-binding motif left open"]},{"year":2012,"claim":"Extended the loss-of-function disease spectrum to a large mammal, showing a catalytic-residue missense mutation causes recessive motor neuron disease in sheep.","evidence":"Homozygosity mapping and candidate-gene sequencing in affected sheep","pmids":["22588130"],"confidence":"Medium","gaps":["No in vitro functional confirmation of the variant","Mechanism in motor neurons not dissected"]},{"year":2018,"claim":"Confirmed in vivo that the carboxypeptidase domain deglutamylates α/β-tubulin and that its loss elevates polyglutamylated tubulin and induces ER stress in Purkinje cells.","evidence":"Conditional Cre-loxP knockout of catalytic-domain exons with tubulin and ER-stress readouts","pmids":["30225910"],"confidence":"High","gaps":["Did not establish how hyperglutamylation triggers ER stress"]},{"year":2020,"claim":"Linked the molecular lesion to the death pathway by showing hyperglutamylated/dimeric tubulin accumulation drives ER stress, UPR, and translation inhibition preceding cell death, reversible by microtubule depolymerization.","evidence":"Single-neuron laser-capture analysis with pharmacological microtubule depolymerizer rescue and ER-stress markers","pmids":["33004692"],"confidence":"High","gaps":["Pharmacological rescue not a genetic proof of pathway","Apoptosis vs necroptosis contribution not resolved"]},{"year":2015,"claim":"Revealed a developmental role outside the nervous system, showing agtpbp1 is required for T lymphocyte development in zebrafish.","evidence":"Transposon mutagenesis plus morpholino knockdown with flow cytometry","pmids":["26161877"],"confidence":"Medium","gaps":["Molecular mechanism in T cells undefined","Not connected to tubulin deglutamylation"]},{"year":2022,"claim":"Separated catalytic from non-catalytic function by showing the N-terminal NLS domain supports hippocampal synaptic GluA2/kinesin-1 trafficking and learning without causing the pcd degenerative phenotype.","evidence":"Exon 3 (NLS) conditional knockout mice with synaptosomal western blots and behavioral testing","pmids":["36361749"],"confidence":"Medium","gaps":["Direct molecular role of NLS domain in trafficking unclear","Residual truncated protein complicates interpretation"]},{"year":2023,"claim":"Established the cell-biological basis of the spermatogenic defect, localizing AGTPBP1 to the manchette and linking its loss to abnormal tubulin glutamylation and human teratozoospermia.","evidence":"Immunolocalization, Agtpbp1-null sperm morphology, tubulin western blots, and human exome sequencing","pmids":["37937809"],"confidence":"Medium","gaps":["Human variants lacked in vitro functional assay","How manchette localization is achieved unknown"]},{"year":2025,"claim":"Confirmed by a catalytic knock-in that deglutamylase activity per se is required for normal sperm morphology, controlling tubulin glutamylation in the sperm head.","evidence":"CRISPR R791H knock-in mouse with sperm morphology and polyglutamylated-tubulin immunofluorescence","pmids":["41160201"],"confidence":"Medium","gaps":["Single residue/model","Did not measure downstream motility mechanisms"]},{"year":2025,"claim":"Implicated AGTPBP1 in neurite outgrowth and dopaminergic/mitochondrial homeostasis via CRMP2, with pharmacological CRMP2 modulation rescuing developmental defects.","evidence":"AGTPBP1 KO cells and zebrafish knockdown with CRMP2 readouts and lacosamide rescue","pmids":["40347376"],"confidence":"Medium","gaps":["Mechanistic link between deglutamylation and CRMP2 unresolved","Single lab"]},{"year":2025,"claim":"Showed therapeutic gain-of-function potential, with Nna1 overexpression suppressing microtubule hyperglutamylation, autophagy, and apoptosis to ameliorate diabetic retinopathy.","evidence":"In vivo and in vitro gain/loss-of-function in Müller cells and diabetic retina with glutamylation and cell-death markers","pmids":["41190783"],"confidence":"Medium","gaps":["Mechanism connecting glutamylation to autophagy in Müller cells not dissected","Single lab"]},{"year":2026,"claim":"Proposed pro-tumorigenic roles for AGTPBP1 through ERK pathway activation in pancreatic and breast cancer cells, via MYLK upregulation and EVPL repression respectively.","evidence":"Gain/loss-of-function in cancer cell lines with RNA-seq, ERK-inhibitor and rescue experiments","pmids":["41930881","41905574"],"confidence":"Low","gaps":["No biochemical reconstitution; mechanism inferred from pharmacology and RNA-seq","Not connected to deglutamylase activity","Cell-line based only, single labs"]},{"year":null,"claim":"How AGTPBP1 is targeted to distinct subcellular sites (manchette, synapse, nucleus) and how tubulin hyperglutamylation is mechanistically transduced into ER stress and translation arrest remain unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model of substrate engagement on the tubulin C-terminal tail","Recruitment mechanism to manchette/synaptosomes unknown","Causal chain from hyperglutamylation to UPR not defined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[4,10,12]},{"term_id":"GO:0016787","term_label":"hydrolase activity","supporting_discovery_ids":[4,10]},{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[10,12,13]}],"localization":[{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[1,6]},{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0,1,15]},{"term_id":"GO:0005856","term_label":"cytoskeleton","supporting_discovery_ids":[12,13,16]}],"pathway":[],"complexes":[],"partners":[],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9UPW5","full_name":"Cytosolic carboxypeptidase 1","aliases":["ATP/GTP-binding protein 1","Nervous system nuclear protein induced by axotomy protein 1 homolog","Protein deglutamylase CCP1"],"length_aa":1226,"mass_kda":138.4,"function":"Metallocarboxypeptidase that mediates protein deglutamylation of tubulin and non-tubulin target proteins (PubMed:22170066, PubMed:24022482, PubMed:30420557). Catalyzes the removal of polyglutamate side chains present on the gamma-carboxyl group of glutamate residues within the C-terminal tail of alpha- and beta-tubulin (PubMed:22170066, PubMed:24022482, PubMed:30420557). Specifically cleaves tubulin long-side-chains, while it is not able to remove the branching point glutamate (PubMed:24022482). Also catalyzes the removal of polyglutamate residues from the carboxy-terminus of alpha-tubulin as well as non-tubulin proteins such as MYLK (PubMed:22170066). Involved in KLF4 deglutamylation which promotes KLF4 proteasome-mediated degradation, thereby negatively regulating cell pluripotency maintenance and embryogenesis (PubMed:29593216)","subcellular_location":"Cytoplasm; Cytoplasm, cytosol; Nucleus; Mitochondrion","url":"https://www.uniprot.org/uniprotkb/Q9UPW5/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/AGTPBP1","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":[{"gene":"CAPZB","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/AGTPBP1","total_profiled":1310},"omim":[{"mim_id":"620694","title":"TUBULIN TYROSINE LIGASE-LIKE 11; TTLL11","url":"https://www.omim.org/entry/620694"},{"mim_id":"619195","title":"TUBULIN TYROSINE LIGASE-LIKE 3; TTLL3","url":"https://www.omim.org/entry/619195"},{"mim_id":"618276","title":"NEURODEGENERATION, CHILDHOOD-ONSET, WITH CEREBELLAR ATROPHY; CONDCA","url":"https://www.omim.org/entry/618276"},{"mim_id":"617346","title":"ATP/GTP-BINDING PROTEIN-LIKE 3; AGBL3","url":"https://www.omim.org/entry/617346"},{"mim_id":"617345","title":"ATP/GTP-BINDING PROTEIN-LIKE 2; AGBL2","url":"https://www.omim.org/entry/617345"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoplasm","reliability":"Supported"},{"location":"Plasma membrane","reliability":"Additional"},{"location":"Primary cilium","reliability":"Additional"},{"location":"Centriolar satellite","reliability":"Additional"},{"location":"Basal body","reliability":"Additional"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in all","driving_tissues":[{"tissue":"bone marrow","ntpm":56.8},{"tissue":"retina","ntpm":43.1}],"url":"https://www.proteinatlas.org/search/AGTPBP1"},"hgnc":{"alias_symbol":["KIAA1035","Nna1","CCP1"],"prev_symbol":[]},"alphafold":{"accession":"Q9UPW5","domains":[{"cath_id":"2.60.40.3120","chopping":"649-846","consensus_level":"high","plddt":90.4916,"start":649,"end":846},{"cath_id":"3.40.630.10","chopping":"853-1144_1168-1174","consensus_level":"medium","plddt":91.3527,"start":853,"end":1174},{"cath_id":"1.20.1050","chopping":"227-326","consensus_level":"medium","plddt":92.8185,"start":227,"end":326}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9UPW5","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9UPW5-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9UPW5-F1-predicted_aligned_error_v6.png","plddt_mean":75.31},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=AGTPBP1","jax_strain_url":"https://www.jax.org/strain/search?query=AGTPBP1"},"sequence":{"accession":"Q9UPW5","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9UPW5.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9UPW5/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9UPW5"}},"corpus_meta":[{"pmid":"11884758","id":"PMC_11884758","title":"Purkinje 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lysyl oxidase propeptide and NF-κB signaling.","date":"2010","source":"Neuron","url":"https://pubmed.ncbi.nlm.nih.gov/20920790","citation_count":63,"is_preprint":false},{"pmid":"20061535","id":"PMC_20061535","title":"CCP1/Nna1 functions in protein turnover in mouse brain: Implications for cell death in Purkinje cell degeneration mice.","date":"2010","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/20061535","citation_count":48,"is_preprint":false},{"pmid":"16952463","id":"PMC_16952463","title":"The carboxypeptidase-like substrate-binding site in Nna1 is essential for the rescue of the Purkinje cell degeneration (pcd) phenotype.","date":"2006","source":"Molecular and cellular neurosciences","url":"https://pubmed.ncbi.nlm.nih.gov/16952463","citation_count":42,"is_preprint":false},{"pmid":"18602413","id":"PMC_18602413","title":"The zinc-binding domain of Nna1 is required to prevent 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associated with cerebellar degeneration and motor neuropathy.","date":"2019","source":"European journal of human genetics : EJHG","url":"https://pubmed.ncbi.nlm.nih.gov/30976113","citation_count":26,"is_preprint":false},{"pmid":"22835831","id":"PMC_22835831","title":"A structural and functional analysis of Nna1 in Purkinje cell degeneration (pcd) mice.","date":"2012","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/22835831","citation_count":22,"is_preprint":false},{"pmid":"22588130","id":"PMC_22588130","title":"A missense mutation in AGTPBP1 was identified in sheep with a lower motor neuron disease.","date":"2012","source":"Heredity","url":"https://pubmed.ncbi.nlm.nih.gov/22588130","citation_count":22,"is_preprint":false},{"pmid":"34572343","id":"PMC_34572343","title":"The Childhood-Onset Neurodegeneration with Cerebellar Atrophy (CONDCA) Disease Caused by AGTPBP1 Gene Mutations: The Purkinje Cell Degeneration Mouse as an Animal Model for the Study of this Human Disease.","date":"2021","source":"Biomedicines","url":"https://pubmed.ncbi.nlm.nih.gov/34572343","citation_count":20,"is_preprint":false},{"pmid":"21110128","id":"PMC_21110128","title":"Abnormal sperm development in pcd(3J)-/- mice: the importance of Agtpbp1 in spermatogenesis.","date":"2010","source":"Molecules and cells","url":"https://pubmed.ncbi.nlm.nih.gov/21110128","citation_count":20,"is_preprint":false},{"pmid":"33004692","id":"PMC_33004692","title":"Nna1 gene deficiency triggers Purkinje neuron death by tubulin hyperglutamylation and ER dysfunction.","date":"2020","source":"JCI insight","url":"https://pubmed.ncbi.nlm.nih.gov/33004692","citation_count":16,"is_preprint":false},{"pmid":"20484972","id":"PMC_20484972","title":"A defect in cytosolic carboxypeptidase 1 (Nna1) causes autophagy in Purkinje cell degeneration mouse 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Purkinje Cell Survival, Is also Associated with Emotion and Memory.","date":"2022","source":"International journal of molecular sciences","url":"https://pubmed.ncbi.nlm.nih.gov/36361749","citation_count":8,"is_preprint":false},{"pmid":"26106267","id":"PMC_26106267","title":"Bioinformatics Data Mining Approach Suggests Coexpression of AGTPBP1 with an ALS-linked Gene C9orf72.","date":"2015","source":"Journal of central nervous system disease","url":"https://pubmed.ncbi.nlm.nih.gov/26106267","citation_count":7,"is_preprint":false},{"pmid":"33909173","id":"PMC_33909173","title":"A novel pathogenic variant in the 3' end of the AGTPBP1 gene gives rise to neurodegeneration without cerebellar atrophy: an expansion of the disease phenotype?","date":"2021","source":"Neurogenetics","url":"https://pubmed.ncbi.nlm.nih.gov/33909173","citation_count":6,"is_preprint":false},{"pmid":"37994971","id":"PMC_37994971","title":"Circ-AGTPBP1 promotes white matter injury through miR-140-3p/Pcdh17 axis role of Circ-AGTPBP1 in white matter injury.","date":"2023","source":"Journal of bioenergetics and biomembranes","url":"https://pubmed.ncbi.nlm.nih.gov/37994971","citation_count":6,"is_preprint":false},{"pmid":"39129004","id":"PMC_39129004","title":"Targeting AGTPBP1 inhibits pancreatic cancer progression via regulating microtubules and ERK signaling pathway.","date":"2024","source":"Molecular medicine (Cambridge, Mass.)","url":"https://pubmed.ncbi.nlm.nih.gov/39129004","citation_count":4,"is_preprint":false},{"pmid":"23121602","id":"PMC_23121602","title":"Analysis of the light-sensitivity of the photoreceptor cells of the ataxia and male sterility (AMS) mouse, an Nna1 mutant.","date":"2012","source":"Pathology international","url":"https://pubmed.ncbi.nlm.nih.gov/23121602","citation_count":4,"is_preprint":false},{"pmid":"41190783","id":"PMC_41190783","title":"Single-Cell RNA Sequencing of Retina Reveals Nna1 Upregulation in Myopic Diabetic Retinopathy as a Protective Factor Against Diabetic Damage.","date":"2025","source":"Advanced science (Weinheim, Baden-Wurttemberg, Germany)","url":"https://pubmed.ncbi.nlm.nih.gov/41190783","citation_count":2,"is_preprint":false},{"pmid":"40347376","id":"PMC_40347376","title":"Lacosamide Is a Novel Drug That Improves AGTPBP1 Knockout-Mediated Impairment of Neuronal and Dopaminergic Function.","date":"2025","source":"Molecular neurobiology","url":"https://pubmed.ncbi.nlm.nih.gov/40347376","citation_count":2,"is_preprint":false},{"pmid":"41160201","id":"PMC_41160201","title":"Human teratozoospermia-related AGTPBP1 R791H mutation is associated with sperm head and tail defects in a CRISPR-engineered murine model.","date":"2025","source":"Journal of assisted reproduction and genetics","url":"https://pubmed.ncbi.nlm.nih.gov/41160201","citation_count":1,"is_preprint":false},{"pmid":"41930881","id":"PMC_41930881","title":"A novel AGTPBP1-ERK/MYLK network mediates pancreatic cancer progression.","date":"2026","source":"Tissue & cell","url":"https://pubmed.ncbi.nlm.nih.gov/41930881","citation_count":0,"is_preprint":false},{"pmid":"41905574","id":"PMC_41905574","title":"AGTPBP1 promotes breast cancer progression via the EVPL/ERK signaling axis.","date":"2026","source":"Experimental cell research","url":"https://pubmed.ncbi.nlm.nih.gov/41905574","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":16765,"output_tokens":5356,"usd":0.065318,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":13736,"output_tokens":5286,"usd":0.100415,"stage2_stop_reason":"end_turn"},"total_usd":0.165733,"stage1_batch_id":"msgbatch_0179Z2pxRYBsXi2xADneafRw","stage2_batch_id":"msgbatch_01LaY9ZaVdgjWArcZo9eqQE5","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2002,\n      \"finding\": \"Nna1 (AGTPBP1) was identified as the gene mutated in the Purkinje cell degeneration (pcd) mouse, encoding a putative nuclear protein with a zinc carboxypeptidase domain; loss-of-function of Nna1 causes degeneration of cerebellar Purkinje neurons, retinal photoreceptors, olfactory bulb mitral neurons, selected thalamic neurons, and defective spermatogenesis.\",\n      \"method\": \"Genetic mapping and sequencing of pcd alleles; identification of mutations in Nna1 in original pcd, pcd2J, and pcd3J alleles\",\n      \"journal\": \"Science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic identification of causal mutations in multiple independent alleles, replicated across alleles\",\n      \"pmids\": [\"11884758\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"Nna1 encodes a zinc carboxypeptidase with nuclear localization signals and an ATP/GTP binding motif; GFP-Nna1 fusion protein localizes to both cytoplasmic and nuclear compartments in cultured neurons.\",\n      \"method\": \"GFP-fusion protein transfection and live-cell imaging in cultured neurons; bioinformatic domain analysis\",\n      \"journal\": \"Molecular and cellular neurosciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — direct localization experiment with GFP fusion, single lab, consistent with subsequent studies\",\n      \"pmids\": [\"11083920\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"The carboxypeptidase substrate-binding site of Nna1 is functionally essential for Purkinje cell survival; a substrate-binding site mutant of Nna1 failed to rescue ataxic behavior and Purkinje cell loss in pcd(3J) mice, whereas wild-type Nna1 did rescue.\",\n      \"method\": \"Transgenic rescue in pcd mice using L7/pcp2 promoter-driven wild-type vs. substrate-binding site mutant Nna1; behavioral and histological analysis\",\n      \"journal\": \"Molecular and cellular neurosciences\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — transgenic rescue with mutagenesis, in vivo functional validation, clear positive vs. negative control\",\n      \"pmids\": [\"16952463\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"The pcd5J allele results from a single aspartic acid insertion at position 775 of Nna1, which does not affect mRNA expression but dramatically destabilizes the Nna1 protein, as shown by pulse-chase experiments.\",\n      \"method\": \"Sequencing of Nna1 in pcd5J mice; pulse-chase protein stability assay\",\n      \"journal\": \"Mammalian genome\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — pulse-chase biochemical assay directly measuring protein stability, single lab with orthogonal sequencing\",\n      \"pmids\": [\"16465590\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Nna1-like proteins constitute a new M14 subfamily (M14D) of metallocarboxypeptidases with an unusually open active site; a C. elegans ortholog was shown to be a fully functional metallocarboxypeptidase cleaving C-terminal amino acids from synthetic peptides, with activity activated by ATP/ADP and preferentially inhibited by Z-Glu-Tyr, resembling tubulin carboxypeptidase activity.\",\n      \"method\": \"Recombinant protein expression and in vitro enzymatic assay with synthetic peptide substrates; phylogenetic and conformational modeling\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution of enzymatic activity with substrate specificity profiling, functional inhibitor characterization\",\n      \"pmids\": [\"17244817\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"The zinc-binding domain of Nna1 is required to prevent retinal photoreceptor loss and Purkinje cell degeneration; a BAC transgene containing wild-type Nna1 rescues these phenotypes in pcd(5J) mice, but mutation of the zinc-binding domain abolishes rescue.\",\n      \"method\": \"BAC transgenic rescue in pcd(5J) mice with wild-type vs. zinc-binding domain mutant Nna1; histological analysis of retina and cerebellum\",\n      \"journal\": \"Vision research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — in vivo transgenic rescue with domain-inactivating mutagenesis, clear functional validation\",\n      \"pmids\": [\"18602413\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"CCP1/Nna1 (AGTPBP1) functions in protein turnover by degrading proteasome-generated peptides into amino acids; pcd mice lacking functional CCP1/Nna1 accumulate hundreds of intracellular peptides from cytosolic and mitochondrial proteins, while proteasome activity is normal, indicating a specific downstream peptide-degradation deficit.\",\n      \"method\": \"Quantitative proteomics and peptidomics comparing pcd mutant vs. wild-type mouse brain regions; 2D gel electrophoresis; proteasome activity assay; autophagy markers\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal biochemical methods (peptidomics, proteomics, enzyme activity assay), single lab\",\n      \"pmids\": [\"20061535\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Loss of CCP1/Nna1 causes elevated autophagy in both degenerating and non-degenerating brain regions of pcd mice, proposed to result from decreased cellular amino acid levels due to failure to degrade proteasome-generated peptides.\",\n      \"method\": \"Autophagy marker analysis in pcd mouse brain regions\",\n      \"journal\": \"Autophagy\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — loss-of-function cellular phenotype with defined marker readout, supported by parallel peptidomics study from same lab\",\n      \"pmids\": [\"20484972\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Mutant Nna1 leads to abnormal Purkinje cell dendrite development through increased intranuclear localization of lysyl oxidase propeptide, which interferes with NF-κB RelA signaling and microtubule-associated protein regulation of microtubule stability.\",\n      \"method\": \"Single-cell gene profiling of pcd(Sid) mouse Purkinje cells; virus-based gene transfer rescue; pathway analysis of NF-κB RelA signaling and MAP-microtubule stability\",\n      \"journal\": \"Neuron\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — viral rescue experiment with pathway analysis, single lab, multiple downstream readouts\",\n      \"pmids\": [\"20920790\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"AGTPBP1 is expressed in spermatogenic cells between late-stage primary spermatocytes and round spermatids; loss of Agtpbp1 in pcd(3J) mice causes apoptosis of differentiating germ cells beginning at the pachytene spermatocyte stage, with altered expression of cyclin B3 and deubiquitinating enzymes USP2 and USP9y.\",\n      \"method\": \"Immunohistochemistry with anti-AGTPBP1 antibody in testes; global gene expression analysis of pcd(3J) testes; histological and apoptosis analysis\",\n      \"journal\": \"Molecules and cells\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct localization by IHC tied to functional loss-of-function phenotype and gene expression changes, single lab\",\n      \"pmids\": [\"21110128\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Recombinant Nna1 is a monomeric metallocarboxypeptidase that removes glutamate from tubulin and preferentially cleaves substrates with 2 or more C-terminal glutamate residues (Vmax for 3 glutamates ~7-fold higher than 2 glutamates); catalytic mutants D1007E, R1078E, and E1094A are inactive; ATP/GTP binding is not required for catalysis or neuronal survival in vivo.\",\n      \"method\": \"Purified recombinant Nna1 enzymatic assay with synthetic substrates and tubulin; active-site mutagenesis; transgenic rescue in pcd mice\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro reconstitution with defined substrates, mutagenesis of catalytic residues, orthogonal in vivo transgenic validation\",\n      \"pmids\": [\"22835831\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"A missense mutation c.2909G>C (p.Arg970Pro) in the AGTPBP1 gene, affecting a conserved residue for catalytic activity, causes autosomal recessive lower motor neuron disease in Romney sheep, establishing that AGTPBP1 loss-of-function causes motor neuron disease in a large mammal.\",\n      \"method\": \"Genome-wide homozygosity mapping; sequencing of candidate gene AGTPBP1; genotyping in affected, carrier, and normal sheep\",\n      \"journal\": \"Heredity\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic mapping and variant identification with 100% phenotype concordance, no in vitro functional assay\",\n      \"pmids\": [\"22588130\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Conditional knockout of the carboxypeptidase domain of Nna1 in mice produces Purkinje cell degeneration with cerebellar ataxia and results in increased polyglutamylated tubulin in the cerebellum, confirming that Nna1 acts as a de-glutamatase on the C-terminus of α- and β-tubulin; ER stress marker CHOP is upregulated in mutant Purkinje cells.\",\n      \"method\": \"Conditional Cre-loxP knockout of exons encoding carboxypeptidase domain; western blot for polyglutamylated tubulin; ER stress markers; histology\",\n      \"journal\": \"Journal of neurochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean conditional KO with defined molecular readout (tubulin glutamylation), multiple orthogonal analyses\",\n      \"pmids\": [\"30225910\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Loss of Nna1 deglutamylase activity leads to hyperglutamylated microtubules and dimeric tubulins accumulating in Purkinje neurons; treatment with a microtubule depolymerizer corrects the glutamylation/deglutamylation ratio and increases Purkinje neuron survival; pcd Purkinje neurons also display ER stress, unfolded protein response, and protein synthesis inhibition preceding death by apoptosis/necroptosis.\",\n      \"method\": \"Laser capture microdissection of single Purkinje neurons; mRNA and protein analysis; pharmacological treatment with microtubule depolymerizer; ER stress marker analysis\",\n      \"journal\": \"JCI insight\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods (single-cell analysis, pharmacological rescue, ER stress markers) in single study\",\n      \"pmids\": [\"33004692\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"agtpbp1 is essential for T lymphocyte development in zebrafish; homozygous agtpbp1 mutants and morpholino knockdown embryos show impaired T cell development at 6 days of age.\",\n      \"method\": \"Gene-breaking transposon mutagenesis; flow cytometry of immune cells; morpholino knockdown confirmation\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic mutant plus morpholino knockdown confirmation, defined cellular phenotype, single lab\",\n      \"pmids\": [\"26161877\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"The N-terminal nuclear localization signal (NLS) of Nna1 is involved in hippocampal function; exon 3 (N-terminal NLS) knockout mice that still express a truncated Nna1 protein do not develop the pcd phenotype but show reduced GluA2 AMPA receptor and kinesin-1 in the hippocampal synaptosomal fraction, along with impaired context- and cue-dependent learning and altered anxiety.\",\n      \"method\": \"Conditional exon 3 knockout mouse; behavioral tests (elevated plus maze, light/dark box, fear conditioning); synaptosomal fractionation and western blot for GluA2 and kinesin-1\",\n      \"journal\": \"International journal of molecular sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean KO with defined molecular readout (synaptosomal GluA2, kinesin-1) and behavioral phenotype, single lab\",\n      \"pmids\": [\"36361749\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"AGTPBP1 is localized to the manchette structure in murine spermatids, and its loss (null mice) causes sperm head and tail defects associated with abnormal polyglutamylated tubulin accumulation and decreased Δ-2 tubulin; in humans, AGTPBP1 missense mutations produce teratozoospermia with sperm head and flagella defects and fragmented/abnormal AGTPBP1 localization in the neck and annulus regions.\",\n      \"method\": \"Immunolocalization in mouse testes; analysis of Agtpbp1-null mouse sperm morphology; western blot for polyglutamylated and Δ-2 tubulin; whole-exome sequencing in human patients\",\n      \"journal\": \"Journal of cellular and molecular medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct localization plus null mouse phenotype with molecular tubulin modification readout, supported by human genetic data\",\n      \"pmids\": [\"37937809\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"AGTPBP1 knockout leads to excessive neurite outgrowth, increased CRMP2 expression, mitochondrial dysfunction, and a hyperdopaminergic state in differentiated neurons in vitro; in zebrafish, AGTPBP1 knockdown causes reduced brain volume and impaired motor function; lacosamide (a CRMP2 modulator) rescues these defects.\",\n      \"method\": \"AGTPBP1 KO cell model; zebrafish knockdown; neurite outgrowth measurement; CRMP2 western blot; mitochondrial function assay; dopamine level measurement; pharmacological rescue with lacosamide\",\n      \"journal\": \"Molecular neurobiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal in vitro and in vivo methods, single lab, pharmacological rescue\",\n      \"pmids\": [\"40347376\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"The R791H knock-in mutation in Agtpbp1 (equivalent to human R811H) causes sperm head and tail defects with abnormal accumulation of polyglutamylated tubulin in the sperm head, confirming that the carboxypeptidase activity of AGTPBP1 is required for proper sperm morphology.\",\n      \"method\": \"CRISPR knock-in mouse model; sperm morphological analysis; immunofluorescence for polyglutamylated tubulin\",\n      \"journal\": \"Journal of assisted reproduction and genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — knock-in murine model with defined molecular readout, single lab, orthogonal morphological and molecular analyses\",\n      \"pmids\": [\"41160201\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Nna1 overexpression in Müller cells suppresses microtubule hyper-glutamylation, reducing autophagy and apoptosis in vitro and ameliorating diabetic retinopathy progression in vivo.\",\n      \"method\": \"In vivo knockdown and overexpression of Nna1 in diabetic mouse retina; in vitro Müller cell experiments; measurement of autophagy and apoptosis markers; polyglutamylation assay\",\n      \"journal\": \"Advanced science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo and in vitro gain- and loss-of-function with defined molecular readout (tubulin glutamylation, autophagy), single lab\",\n      \"pmids\": [\"41190783\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"AGTPBP1 promotes pancreatic cancer cell proliferation and migration through activation of the MAPK/ERK pathway (increased ERK1/2 phosphorylation) and upregulation of MYLK at the transcriptional level; ERK signaling controls MYLK activity post-translationally without affecting MYLK expression.\",\n      \"method\": \"Gain-of-function and siRNA knockdown in PANC-1/AsPC-1 cells; ERK inhibitor (PD98059) rescue experiments; western blot; RNA-seq; IHC\",\n      \"journal\": \"Tissue & cell\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, cell-line based, no in vitro biochemical reconstitution, mechanism inferred from pharmacological inhibition\",\n      \"pmids\": [\"41930881\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"AGTPBP1 promotes breast cancer progression by repressing envoplakin (EVPL) expression, leading to ERK1/2 activation; rescue experiments confirmed that EVPL overexpression attenuates AGTPBP1-induced malignant phenotypes and ERK activation.\",\n      \"method\": \"Stable overexpression and knockdown in T47D and MDA-MB-231 cells; RNA-sequencing; rescue experiments with EVPL overexpression; western blot for ERK phosphorylation\",\n      \"journal\": \"Experimental cell research\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, cell-line based, no biochemical reconstitution, mechanism inferred from RNA-seq and rescue\",\n      \"pmids\": [\"41905574\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"AGTPBP1/Nna1 is a monomeric M14D-subfamily metallocarboxypeptidase (cytosolic carboxypeptidase 1, CCP1) that removes C-terminal glutamate residues from polyglutamylated substrates—most notably α- and β-tubulin—using a catalytically essential zinc-binding domain; loss of this deglutamylase activity causes hyperglutamylation of microtubules, ER stress, disrupted protein turnover downstream of the proteasome, and consequent degeneration of cerebellar Purkinje cells, retinal photoreceptors, olfactory mitral neurons, and motor neurons, as well as defective spermatogenesis, while its N-terminal nuclear localization domain has additional roles in hippocampal synaptic receptor trafficking.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"AGTPBP1/Nna1 (cytosolic carboxypeptidase 1, CCP1) is a monomeric zinc metallocarboxypeptidase of the M14D subfamily that removes C-terminal glutamate residues from polyglutamylated substrates, most notably α- and β-tubulin, with a preference for substrates carrying two or more terminal glutamates [#4, #10, #12]. Its catalytic activity depends on an intact zinc-binding and substrate-binding active site, and active-site or zinc-domain mutations abolish both enzymatic function and the ability to rescue neurodegeneration in vivo [#2, #5, #10]. Loss of this deglutamylase activity produces hyperglutamylated, destabilized microtubules and triggers ER stress, the unfolded protein response, and protein-synthesis inhibition that precede neuronal death, a degenerative cascade pharmacologically reversible by microtubule depolymerization [#12, #13]. AGTPBP1 was originally identified as the gene mutated in the Purkinje cell degeneration (pcd) mouse, where loss of function causes degeneration of cerebellar Purkinje neurons, retinal photoreceptors, olfactory mitral neurons, and selected thalamic neurons, together with defective spermatogenesis [#0]; recessive loss-of-function variants further cause motor neuron disease in sheep and teratozoospermia in humans, where AGTPBP1 localizes to the spermatid manchette and its catalytic activity is required for normal sperm head and tail morphology [#11, #16, #18]. Beyond tubulin deglutamylation, AGTPBP1 contributes to downstream protein turnover by degrading proteasome-generated peptides into amino acids, and its loss elevates autophagy [#6, #7]. A distinct N-terminal nuclear-localization domain, separable from catalytic function, supports hippocampal synaptic trafficking of the GluA2 AMPA receptor and kinesin-1 [#15].\"\n  ,\n  \"teleology\": [\n    {\n      \"year\": 2000,\n      \"claim\": \"Established the domain architecture and dual nuclear/cytoplasmic localization of Nna1, framing it as a carboxypeptidase with regulatory nucleotide-binding and nuclear-targeting features.\",\n      \"evidence\": \"GFP-fusion live imaging in cultured neurons plus bioinformatic domain analysis\",\n      \"pmids\": [\"11083920\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Localization from overexpressed GFP fusion only\", \"Did not test enzymatic activity or substrate\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Identified Nna1 as the gene causally mutated in the pcd mouse, linking its loss to a defined multi-tissue degenerative phenotype before any biochemical function was known.\",\n      \"evidence\": \"Genetic mapping and sequencing of multiple independent pcd alleles\",\n      \"pmids\": [\"11884758\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not define molecular substrate or catalytic mechanism\", \"Causal cell-biological lesion unknown\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Demonstrated that the carboxypeptidase substrate-binding site is functionally required in vivo, showing the degenerative phenotype reflects loss of enzymatic activity rather than a structural role.\",\n      \"evidence\": \"Transgenic rescue of pcd mice with wild-type vs. substrate-binding-site mutant Nna1\",\n      \"pmids\": [\"16952463\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Endogenous substrate not yet identified\", \"Did not localize where catalysis acts\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Showed a single-residue insertion (pcd5J) destabilizes the protein without affecting mRNA, establishing protein stability as a route to functional loss.\",\n      \"evidence\": \"Sequencing plus pulse-chase protein stability assay\",\n      \"pmids\": [\"16465590\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of destabilization not defined\", \"Did not test residual activity of mutant\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Provided the first direct enzymatic evidence by reconstituting metallocarboxypeptidase activity from a Nna1 ortholog, defining the M14D subfamily and a tubulin-carboxypeptidase-like specificity.\",\n      \"evidence\": \"Recombinant C. elegans ortholog in vitro assay with synthetic peptides and inhibitor profiling\",\n      \"pmids\": [\"17244817\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Used ortholog rather than mammalian protein\", \"Tubulin substrate not directly demonstrated here\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Confirmed the zinc-binding domain is essential in vivo, tying the catalytic metal center to prevention of photoreceptor and Purkinje cell loss.\",\n      \"evidence\": \"BAC transgenic rescue of pcd5J with wild-type vs. zinc-domain mutant Nna1\",\n      \"pmids\": [\"18602413\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not measure substrate modification in rescued tissue\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Linked AGTPBP1 to bulk protein turnover by showing pcd mice accumulate proteasome-generated peptides with normal proteasome activity, and that resulting amino acid scarcity elevates autophagy.\",\n      \"evidence\": \"Peptidomics/proteomics, proteasome activity assays, and autophagy markers in pcd mouse brain\",\n      \"pmids\": [\"20061535\", \"20484972\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not establish whether peptide accumulation is a direct catalytic deficit or secondary\", \"Relationship to tubulin deglutamylation unresolved at this stage\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Identified downstream signaling consequences of Nna1 loss in Purkinje dendrite development through intranuclear lysyl oxidase propeptide affecting NF-κB RelA and MAP-microtubule stability.\",\n      \"evidence\": \"Single-cell profiling and viral rescue in pcd Purkinje cells with pathway analysis\",\n      \"pmids\": [\"20920790\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Causal chain from carboxypeptidase loss to lysyl oxidase indirect\", \"Single lab pathway inference\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Connected AGTPBP1 to spermatogenesis, defining its germ-cell expression window and the apoptotic stage of germ-cell loss upon its mutation.\",\n      \"evidence\": \"IHC and gene-expression analysis in pcd3J testes\",\n      \"pmids\": [\"21110128\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Did not link to tubulin modification mechanism\", \"Gene-expression changes correlative\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Definitively reconstituted mammalian Nna1 as a monomeric deglutamylase removing glutamate from tubulin with chain-length preference, identified catalytic residues, and showed ATP/GTP binding is dispensable for catalysis and neuronal survival.\",\n      \"evidence\": \"Purified recombinant Nna1 assays with tubulin/synthetic substrates, active-site mutagenesis, transgenic rescue\",\n      \"pmids\": [\"22835831\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not address in vivo glutamylation balance directly\", \"Function of the nucleotide-binding motif left open\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Extended the loss-of-function disease spectrum to a large mammal, showing a catalytic-residue missense mutation causes recessive motor neuron disease in sheep.\",\n      \"evidence\": \"Homozygosity mapping and candidate-gene sequencing in affected sheep\",\n      \"pmids\": [\"22588130\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No in vitro functional confirmation of the variant\", \"Mechanism in motor neurons not dissected\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Confirmed in vivo that the carboxypeptidase domain deglutamylates α/β-tubulin and that its loss elevates polyglutamylated tubulin and induces ER stress in Purkinje cells.\",\n      \"evidence\": \"Conditional Cre-loxP knockout of catalytic-domain exons with tubulin and ER-stress readouts\",\n      \"pmids\": [\"30225910\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not establish how hyperglutamylation triggers ER stress\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Linked the molecular lesion to the death pathway by showing hyperglutamylated/dimeric tubulin accumulation drives ER stress, UPR, and translation inhibition preceding cell death, reversible by microtubule depolymerization.\",\n      \"evidence\": \"Single-neuron laser-capture analysis with pharmacological microtubule depolymerizer rescue and ER-stress markers\",\n      \"pmids\": [\"33004692\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Pharmacological rescue not a genetic proof of pathway\", \"Apoptosis vs necroptosis contribution not resolved\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Revealed a developmental role outside the nervous system, showing agtpbp1 is required for T lymphocyte development in zebrafish.\",\n      \"evidence\": \"Transposon mutagenesis plus morpholino knockdown with flow cytometry\",\n      \"pmids\": [\"26161877\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular mechanism in T cells undefined\", \"Not connected to tubulin deglutamylation\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Separated catalytic from non-catalytic function by showing the N-terminal NLS domain supports hippocampal synaptic GluA2/kinesin-1 trafficking and learning without causing the pcd degenerative phenotype.\",\n      \"evidence\": \"Exon 3 (NLS) conditional knockout mice with synaptosomal western blots and behavioral testing\",\n      \"pmids\": [\"36361749\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct molecular role of NLS domain in trafficking unclear\", \"Residual truncated protein complicates interpretation\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Established the cell-biological basis of the spermatogenic defect, localizing AGTPBP1 to the manchette and linking its loss to abnormal tubulin glutamylation and human teratozoospermia.\",\n      \"evidence\": \"Immunolocalization, Agtpbp1-null sperm morphology, tubulin western blots, and human exome sequencing\",\n      \"pmids\": [\"37937809\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Human variants lacked in vitro functional assay\", \"How manchette localization is achieved unknown\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Confirmed by a catalytic knock-in that deglutamylase activity per se is required for normal sperm morphology, controlling tubulin glutamylation in the sperm head.\",\n      \"evidence\": \"CRISPR R791H knock-in mouse with sperm morphology and polyglutamylated-tubulin immunofluorescence\",\n      \"pmids\": [\"41160201\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single residue/model\", \"Did not measure downstream motility mechanisms\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Implicated AGTPBP1 in neurite outgrowth and dopaminergic/mitochondrial homeostasis via CRMP2, with pharmacological CRMP2 modulation rescuing developmental defects.\",\n      \"evidence\": \"AGTPBP1 KO cells and zebrafish knockdown with CRMP2 readouts and lacosamide rescue\",\n      \"pmids\": [\"40347376\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanistic link between deglutamylation and CRMP2 unresolved\", \"Single lab\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Showed therapeutic gain-of-function potential, with Nna1 overexpression suppressing microtubule hyperglutamylation, autophagy, and apoptosis to ameliorate diabetic retinopathy.\",\n      \"evidence\": \"In vivo and in vitro gain/loss-of-function in Müller cells and diabetic retina with glutamylation and cell-death markers\",\n      \"pmids\": [\"41190783\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism connecting glutamylation to autophagy in Müller cells not dissected\", \"Single lab\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Proposed pro-tumorigenic roles for AGTPBP1 through ERK pathway activation in pancreatic and breast cancer cells, via MYLK upregulation and EVPL repression respectively.\",\n      \"evidence\": \"Gain/loss-of-function in cancer cell lines with RNA-seq, ERK-inhibitor and rescue experiments\",\n      \"pmids\": [\"41930881\", \"41905574\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No biochemical reconstitution; mechanism inferred from pharmacology and RNA-seq\", \"Not connected to deglutamylase activity\", \"Cell-line based only, single labs\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How AGTPBP1 is targeted to distinct subcellular sites (manchette, synapse, nucleus) and how tubulin hyperglutamylation is mechanistically transduced into ER stress and translation arrest remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model of substrate engagement on the tubulin C-terminal tail\", \"Recruitment mechanism to manchette/synaptosomes unknown\", \"Causal chain from hyperglutamylation to UPR not defined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [4, 10, 12]},\n      {\"term_id\": \"GO:0016787\", \"supporting_discovery_ids\": [4, 10]},\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [10, 12, 13]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [1, 6]},\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0, 1, 15]},\n      {\"term_id\": \"GO:0005856\", \"supporting_discovery_ids\": [12, 13, 16]}\n    ],\n    \"pathway\": [],\n    \"complexes\": [],\n    \"partners\": [],\n    \"other_free_text\": []\n  }\n}\n```","audit_flag":null,"evaluation":{"pairwise":"tie","faith_supported":6,"faith_total":6,"faith_pct":100.0}}