{"gene":"CACNG8","run_date":"2026-04-28T17:28:52","timeline":{"discoveries":[{"year":2016,"finding":"CACNG8 (TARP-γ8) functions as an accessory protein required for the activity of novel AMPA receptor modulators; using calcium flux, radioligand binding, and electrophysiology with wild-type and mutant forms of TARP-γ8, the mechanism was defined as partial disruption of the interaction between TARP-γ8 and the pore-forming AMPA receptor subunit.","method":"Calcium flux assay, radioligand binding, electrophysiology with wild-type and mutant TARP-γ8","journal":"The Journal of pharmacology and experimental therapeutics","confidence":"High","confidence_rationale":"Tier 1 — multiple orthogonal in vitro assays plus mutagenesis in a single study","pmids":["26989142"],"is_preprint":false},{"year":2022,"finding":"Knockout of TARP γ-8 (CACNG8) in mice causes ADHD-like behaviors (hyperactivity, impulsivity, impaired cognition); synaptosomal proteomics showed dysfunction of the AMPA glutamate receptor complex in hippocampus and dysregulation of dopaminergic and glutamatergic transmission in prefrontal cortex; methylphenidate rescued behavioral deficits and abnormal synaptosomal proteins.","method":"TARP γ-8 knockout mouse model, behavioral assays, synaptosomal proteomics, pharmacological rescue with methylphenidate","journal":"Zoological research","confidence":"High","confidence_rationale":"Tier 2 — clean KO with defined behavioral phenotype plus proteomic pathway placement and pharmacological rescue","pmids":["36031768"],"is_preprint":false},{"year":2021,"finding":"Decreased TARP γ-8 (CACNG8) expression impairs synaptic AMPA receptor function specifically in layer 2–3 pyramidal neurons of the prefrontal cortex; a G-quadruplex-forming SNP (rs10420324G) in the CACNG8 gene suppresses its transcription, reducing AMPAR-mediated excitatory transmission in prefrontal cortex.","method":"Knockout/heterozygous mouse behavioral analysis, electrophysiology of prefrontal cortex pyramidal neurons, reporter gene assay for G-quadruplex transcriptional regulation","journal":"Scientific reports","confidence":"High","confidence_rationale":"Tier 2 — electrophysiology of defined neuron type plus reporter assay for SNP mechanism, multiple orthogonal methods","pmids":["34099816"],"is_preprint":false},{"year":2025,"finding":"CACNG8 encodes TARP γ-8, which regulates AMPA receptor (AMPAR) trafficking, gating, and synaptic localization; rare variants including stop-gain (p.Arg123Ter) and missense variants (p.Leu96Val, p.Val102Met) severely reduce stability of postsynaptic AMPAR complexes (ΔΔG >20 kcal/mol), disrupt binding geometry with auxiliary subunits and scaffolding proteins (PSD93, PSD95, CNIH2/3), reduce hydrogen bonding, and increase conformational disorder as shown by molecular dynamics simulations and MM-PBSA/MM-GBSA analyses.","method":"Whole exome sequencing, molecular docking, MM-PBSA/MM-GBSA free energy calculation, molecular dynamics simulation, GIST and PCA/TICA analyses","journal":"Computational and structural biotechnology journal","confidence":"Medium","confidence_rationale":"Tier 1 method (structural/computational) but single lab, no experimental validation of simulations","pmids":["41127817"],"is_preprint":false}],"current_model":"CACNG8 encodes TARP γ-8, an AMPA receptor auxiliary subunit that physically interacts with the pore-forming AMPAR subunit to regulate receptor trafficking, gating, and synaptic localization; disruption of this interaction (by small molecules, loss-of-function mutations, or gene knockout) impairs AMPAR-mediated excitatory synaptic transmission particularly in hippocampus and prefrontal cortex, leading to behavioral deficits including ADHD-like phenotypes and impaired impulse control."},"narrative":{"teleology":[{"year":2016,"claim":"Establishing that TARP γ-8 is not merely an AMPAR-associated protein but is mechanistically required for receptor modulation resolved how auxiliary subunits control AMPAR pharmacology.","evidence":"Calcium flux, radioligand binding, and electrophysiology with wild-type and mutant TARP γ-8 showing that novel AMPAR modulators act by partially disrupting the TARP γ-8–AMPAR pore subunit interaction","pmids":["26989142"],"confidence":"High","gaps":["Exact binding interface between TARP γ-8 and AMPAR subunit not structurally resolved","Whether other TARPs can substitute for γ-8 in this pharmacological mechanism not tested"]},{"year":2021,"claim":"Demonstrating that reduced CACNG8 expression selectively impairs AMPAR-mediated transmission in prefrontal cortex layer 2–3 pyramidal neurons linked a transcription-level regulatory variant to a defined synaptic deficit.","evidence":"Electrophysiology in heterozygous/KO mouse prefrontal cortex slices combined with reporter gene assay showing a G-quadruplex-forming SNP (rs10420324G) suppresses CACNG8 transcription","pmids":["34099816"],"confidence":"High","gaps":["Whether the G-quadruplex SNP affects CACNG8 expression in human neurons not shown","Cell-type specificity of TARP γ-8 dependency beyond layer 2–3 pyramidal neurons unclear"]},{"year":2022,"claim":"Full knockout revealed that TARP γ-8 loss produces a composite behavioral phenotype (ADHD-like hyperactivity, impulsivity, cognitive impairment) driven by AMPAR complex dysfunction and dopaminergic/glutamatergic pathway dysregulation, establishing an in vivo systems-level role.","evidence":"TARP γ-8 knockout mouse behavioral battery, synaptosomal proteomics in hippocampus and prefrontal cortex, pharmacological rescue with methylphenidate","pmids":["36031768"],"confidence":"High","gaps":["Whether conditional or region-specific knockout recapitulates the full behavioral syndrome not tested","Direct causality between proteomic changes and specific behavioral outputs not established"]},{"year":2025,"claim":"Computational analysis of rare human CACNG8 variants predicted severe destabilization of postsynaptic AMPAR complexes and disrupted interactions with scaffolding partners, extending the loss-of-function mechanism to specific human mutations.","evidence":"Whole exome sequencing identifying stop-gain (p.Arg123Ter) and missense variants, followed by molecular docking, MM-PBSA/MM-GBSA, and molecular dynamics simulations of AMPAR–TARP γ-8–scaffold complexes","pmids":["41127817"],"confidence":"Medium","gaps":["Computational predictions of destabilization have not been experimentally validated by binding assays or electrophysiology","Clinical phenotypes of individuals carrying these rare variants not fully characterized","Whether these variants act through haploinsufficiency or dominant-negative mechanisms is unknown"]},{"year":null,"claim":"A high-resolution experimental structure of the full TARP γ-8–AMPAR–scaffold ternary complex is needed to validate computational models and define the precise molecular interfaces disrupted by disease-associated mutations.","evidence":"","pmids":[],"confidence":"High","gaps":["No experimental atomic structure of the full TARP γ-8–AMPAR–PSD-95/CNIH ternary complex","Mechanism by which TARP γ-8 loss differentially affects glutamatergic versus dopaminergic circuits is unresolved","Whether CACNG8 variants contribute to human ADHD or other neurodevelopmental disorders through Mendelian or complex-trait mechanisms is undetermined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[0,2,3]}],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[0,2,3]}],"pathway":[{"term_id":"R-HSA-112316","term_label":"Neuronal System","supporting_discovery_ids":[0,1,2]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[1,2]}],"complexes":["AMPA receptor complex"],"partners":["GRIA1","GRIA2","PSD93","PSD95","CNIH2","CNIH3"],"other_free_text":[]},"mechanistic_narrative":"CACNG8 encodes TARP γ-8, a transmembrane AMPA receptor regulatory protein (TARP) that functions as an auxiliary subunit of AMPA receptors to control their trafficking, gating, and synaptic localization, particularly in hippocampal and prefrontal cortical circuits [PMID:26989142, PMID:34099816]. TARP γ-8 physically associates with the AMPAR pore-forming subunit, and disruption of this interaction—by pharmacological modulators, loss-of-function mutations, or gene knockout—impairs AMPAR-mediated excitatory synaptic transmission in layer 2–3 prefrontal cortex pyramidal neurons and hippocampus [PMID:26989142, PMID:34099816, PMID:36031768]. Knockout of CACNG8 in mice produces ADHD-like behavioral phenotypes including hyperactivity, impulsivity, and cognitive impairment, with synaptosomal proteomic evidence of disrupted glutamatergic and dopaminergic signaling that is rescued by methylphenidate [PMID:36031768]. Rare human variants including stop-gain and missense mutations destabilize postsynaptic AMPAR complexes and disrupt binding to scaffolding proteins PSD-93, PSD-95, and CNIH2/3 [PMID:41127817]."},"prefetch_data":{"uniprot":{"accession":"Q8WXS5","full_name":"Voltage-dependent calcium channel gamma-8 subunit","aliases":["Neuronal voltage-gated calcium channel gamma-8 subunit","Transmembrane AMPAR regulatory protein gamma-8","TARP gamma-8"],"length_aa":425,"mass_kda":43.3,"function":"Regulates the activity of L-type calcium channels that contain CACNA1C as pore-forming subunit (By similarity). Regulates the trafficking and gating properties of AMPA-selective glutamate receptors (AMPARs). Promotes their targeting to the cell membrane and synapses and modulates their gating properties by slowing their rates of activation, deactivation and desensitization and by mediating their resensitization. Does not show subunit-specific AMPA receptor regulation and regulates all AMPAR subunits","subcellular_location":"Cell membrane; Postsynaptic density membrane","url":"https://www.uniprot.org/uniprotkb/Q8WXS5/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/CACNG8","classification":"Not Classified","n_dependent_lines":1,"n_total_lines":1208,"dependency_fraction":0.0008278145695364238},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/CACNG8","total_profiled":1310},"omim":[{"mim_id":"606900","title":"CALCIUM CHANNEL, VOLTAGE-DEPENDENT, GAMMA-8 SUBUNIT; CACNG8","url":"https://www.omim.org/entry/606900"},{"mim_id":"606899","title":"CALCIUM CHANNEL, VOLTAGE-DEPENDENT, GAMMA-7 SUBUNIT; CACNG7","url":"https://www.omim.org/entry/606899"},{"mim_id":"606898","title":"CALCIUM CHANNEL, VOLTAGE-DEPENDENT, GAMMA-6 SUBUNIT; CACNG6","url":"https://www.omim.org/entry/606898"},{"mim_id":"606404","title":"CALCIUM CHANNEL, VOLTAGE-DEPENDENT, GAMMA-4 SUBUNIT; CACNG4","url":"https://www.omim.org/entry/606404"},{"mim_id":"605366","title":"OLFACTOMEDIN 1; OLFM1","url":"https://www.omim.org/entry/605366"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Tissue enriched","tissue_distribution":"Detected in single","driving_tissues":[{"tissue":"brain","ntpm":34.0}],"url":"https://www.proteinatlas.org/search/CACNG8"},"hgnc":{"alias_symbol":[],"prev_symbol":[]},"alphafold":{"accession":"Q8WXS5","domains":[{"cath_id":"1.20.140.150","chopping":"25-43_118-187_201-239","consensus_level":"medium","plddt":84.195,"start":25,"end":239}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8WXS5","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q8WXS5-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q8WXS5-F1-predicted_aligned_error_v6.png","plddt_mean":58.66},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=CACNG8","jax_strain_url":"https://www.jax.org/strain/search?query=CACNG8"},"sequence":{"accession":"Q8WXS5","fasta_url":"https://rest.uniprot.org/uniprotkb/Q8WXS5.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q8WXS5/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8WXS5"}},"corpus_meta":[{"pmid":"26989142","id":"PMC_26989142","title":"Discovery and Characterization of AMPA Receptor Modulators Selective for TARP-γ8.","date":"2016","source":"The Journal of pharmacology and experimental therapeutics","url":"https://pubmed.ncbi.nlm.nih.gov/26989142","citation_count":88,"is_preprint":false},{"pmid":"27102562","id":"PMC_27102562","title":"Evaluation of voltage-dependent calcium channel γ gene families identified several novel potential susceptible genes to schizophrenia.","date":"2016","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/27102562","citation_count":54,"is_preprint":false},{"pmid":"36490268","id":"PMC_36490268","title":"The impact of modifier genes on cone-rod dystrophy heterogeneity: An explorative familial pilot study and a hypothesis on neurotransmission impairment.","date":"2022","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/36490268","citation_count":38,"is_preprint":false},{"pmid":"38663526","id":"PMC_38663526","title":"Baicalin restore intestinal damage after early-life antibiotic therapy: the role of the MAPK signaling pathway.","date":"2024","source":"Pharmacological research","url":"https://pubmed.ncbi.nlm.nih.gov/38663526","citation_count":22,"is_preprint":false},{"pmid":"31213979","id":"PMC_31213979","title":"Proestrus Differentially Regulates Expression of Ion Channel and Calcium Homeostasis Genes in GnRH Neurons of Mice.","date":"2019","source":"Frontiers in molecular neuroscience","url":"https://pubmed.ncbi.nlm.nih.gov/31213979","citation_count":20,"is_preprint":false},{"pmid":"36031768","id":"PMC_36031768","title":"Deficiency of transmembrane AMPA receptor regulatory protein γ-8 leads to attention-deficit hyperactivity disorder-like behavior in mice.","date":"2022","source":"Zoological research","url":"https://pubmed.ncbi.nlm.nih.gov/36031768","citation_count":18,"is_preprint":false},{"pmid":"31192134","id":"PMC_31192134","title":"Somatic Mutations Profile of a Young Patient With Metastatic Urothelial Carcinoma Reveals Mutations in Genes Involved in Ion Channels.","date":"2019","source":"Frontiers in oncology","url":"https://pubmed.ncbi.nlm.nih.gov/31192134","citation_count":14,"is_preprint":false},{"pmid":"26710323","id":"PMC_26710323","title":"Patients with Dilated Cardiomyopathy and Sustained Monomorphic Ventricular Tachycardia Show Up-Regulation of KCNN3 and KCNJ2 Genes and CACNG8-Linked Left Ventricular Dysfunction.","date":"2015","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/26710323","citation_count":13,"is_preprint":false},{"pmid":"34099816","id":"PMC_34099816","title":"SNP rs10420324 in the AMPA receptor auxiliary subunit TARP γ-8 regulates the susceptibility to antisocial personality disorder.","date":"2021","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/34099816","citation_count":12,"is_preprint":false},{"pmid":"36624125","id":"PMC_36624125","title":"Patient-specific identification of genome-wide DNA-methylation differences between intracranial and extracranial melanoma metastases.","date":"2023","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/36624125","citation_count":11,"is_preprint":false},{"pmid":"39564730","id":"PMC_39564730","title":"Blood Plasma Methylated DNA Markers in the Detection of Lymphoma: Discovery, Validation, and Clinical Pilot.","date":"2024","source":"American journal of hematology","url":"https://pubmed.ncbi.nlm.nih.gov/39564730","citation_count":8,"is_preprint":false},{"pmid":"32391085","id":"PMC_32391085","title":"Whole-genome mate-pair sequencing of apparently balanced chromosome rearrangements reveals complex structural variations: two case studies.","date":"2020","source":"Molecular cytogenetics","url":"https://pubmed.ncbi.nlm.nih.gov/32391085","citation_count":8,"is_preprint":false},{"pmid":"39329756","id":"PMC_39329756","title":"Cannabinol (CBN) Influences the Ion Channels and Synaptic-Related Genes in NSC-34 Cell Line: A Transcriptomic 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brain","url":"https://pubmed.ncbi.nlm.nih.gov/41327336","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":12183,"output_tokens":1167,"usd":0.027027},"stage2":{"model":"claude-opus-4-6","input_tokens":4390,"output_tokens":1676,"usd":0.095775},"total_usd":0.122802,"stage1_batch_id":"msgbatch_011kfMfE81o6CTcyhVUqumuW","stage2_batch_id":"msgbatch_01DTputS6WNkH745x1nVSoBo","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2016,\n      \"finding\": \"CACNG8 (TARP-γ8) functions as an accessory protein required for the activity of novel AMPA receptor modulators; using calcium flux, radioligand binding, and electrophysiology with wild-type and mutant forms of TARP-γ8, the mechanism was defined as partial disruption of the interaction between TARP-γ8 and the pore-forming AMPA receptor subunit.\",\n      \"method\": \"Calcium flux assay, radioligand binding, electrophysiology with wild-type and mutant TARP-γ8\",\n      \"journal\": \"The Journal of pharmacology and experimental therapeutics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — multiple orthogonal in vitro assays plus mutagenesis in a single study\",\n      \"pmids\": [\"26989142\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Knockout of TARP γ-8 (CACNG8) in mice causes ADHD-like behaviors (hyperactivity, impulsivity, impaired cognition); synaptosomal proteomics showed dysfunction of the AMPA glutamate receptor complex in hippocampus and dysregulation of dopaminergic and glutamatergic transmission in prefrontal cortex; methylphenidate rescued behavioral deficits and abnormal synaptosomal proteins.\",\n      \"method\": \"TARP γ-8 knockout mouse model, behavioral assays, synaptosomal proteomics, pharmacological rescue with methylphenidate\",\n      \"journal\": \"Zoological research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — clean KO with defined behavioral phenotype plus proteomic pathway placement and pharmacological rescue\",\n      \"pmids\": [\"36031768\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"Decreased TARP γ-8 (CACNG8) expression impairs synaptic AMPA receptor function specifically in layer 2–3 pyramidal neurons of the prefrontal cortex; a G-quadruplex-forming SNP (rs10420324G) in the CACNG8 gene suppresses its transcription, reducing AMPAR-mediated excitatory transmission in prefrontal cortex.\",\n      \"method\": \"Knockout/heterozygous mouse behavioral analysis, electrophysiology of prefrontal cortex pyramidal neurons, reporter gene assay for G-quadruplex transcriptional regulation\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — electrophysiology of defined neuron type plus reporter assay for SNP mechanism, multiple orthogonal methods\",\n      \"pmids\": [\"34099816\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"CACNG8 encodes TARP γ-8, which regulates AMPA receptor (AMPAR) trafficking, gating, and synaptic localization; rare variants including stop-gain (p.Arg123Ter) and missense variants (p.Leu96Val, p.Val102Met) severely reduce stability of postsynaptic AMPAR complexes (ΔΔG >20 kcal/mol), disrupt binding geometry with auxiliary subunits and scaffolding proteins (PSD93, PSD95, CNIH2/3), reduce hydrogen bonding, and increase conformational disorder as shown by molecular dynamics simulations and MM-PBSA/MM-GBSA analyses.\",\n      \"method\": \"Whole exome sequencing, molecular docking, MM-PBSA/MM-GBSA free energy calculation, molecular dynamics simulation, GIST and PCA/TICA analyses\",\n      \"journal\": \"Computational and structural biotechnology journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 method (structural/computational) but single lab, no experimental validation of simulations\",\n      \"pmids\": [\"41127817\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"CACNG8 encodes TARP γ-8, an AMPA receptor auxiliary subunit that physically interacts with the pore-forming AMPAR subunit to regulate receptor trafficking, gating, and synaptic localization; disruption of this interaction (by small molecules, loss-of-function mutations, or gene knockout) impairs AMPAR-mediated excitatory synaptic transmission particularly in hippocampus and prefrontal cortex, leading to behavioral deficits including ADHD-like phenotypes and impaired impulse control.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"CACNG8 encodes TARP γ-8, a transmembrane AMPA receptor regulatory protein (TARP) that functions as an auxiliary subunit of AMPA receptors to control their trafficking, gating, and synaptic localization, particularly in hippocampal and prefrontal cortical circuits [PMID:26989142, PMID:34099816]. TARP γ-8 physically associates with the AMPAR pore-forming subunit, and disruption of this interaction—by pharmacological modulators, loss-of-function mutations, or gene knockout—impairs AMPAR-mediated excitatory synaptic transmission in layer 2–3 prefrontal cortex pyramidal neurons and hippocampus [PMID:26989142, PMID:34099816, PMID:36031768]. Knockout of CACNG8 in mice produces ADHD-like behavioral phenotypes including hyperactivity, impulsivity, and cognitive impairment, with synaptosomal proteomic evidence of disrupted glutamatergic and dopaminergic signaling that is rescued by methylphenidate [PMID:36031768]. Rare human variants including stop-gain and missense mutations destabilize postsynaptic AMPAR complexes and disrupt binding to scaffolding proteins PSD-93, PSD-95, and CNIH2/3 [PMID:41127817].\",\n  \"teleology\": [\n    {\n      \"year\": 2016,\n      \"claim\": \"Establishing that TARP γ-8 is not merely an AMPAR-associated protein but is mechanistically required for receptor modulation resolved how auxiliary subunits control AMPAR pharmacology.\",\n      \"evidence\": \"Calcium flux, radioligand binding, and electrophysiology with wild-type and mutant TARP γ-8 showing that novel AMPAR modulators act by partially disrupting the TARP γ-8–AMPAR pore subunit interaction\",\n      \"pmids\": [\"26989142\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Exact binding interface between TARP γ-8 and AMPAR subunit not structurally resolved\",\n        \"Whether other TARPs can substitute for γ-8 in this pharmacological mechanism not tested\"\n      ]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Demonstrating that reduced CACNG8 expression selectively impairs AMPAR-mediated transmission in prefrontal cortex layer 2–3 pyramidal neurons linked a transcription-level regulatory variant to a defined synaptic deficit.\",\n      \"evidence\": \"Electrophysiology in heterozygous/KO mouse prefrontal cortex slices combined with reporter gene assay showing a G-quadruplex-forming SNP (rs10420324G) suppresses CACNG8 transcription\",\n      \"pmids\": [\"34099816\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Whether the G-quadruplex SNP affects CACNG8 expression in human neurons not shown\",\n        \"Cell-type specificity of TARP γ-8 dependency beyond layer 2–3 pyramidal neurons unclear\"\n      ]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Full knockout revealed that TARP γ-8 loss produces a composite behavioral phenotype (ADHD-like hyperactivity, impulsivity, cognitive impairment) driven by AMPAR complex dysfunction and dopaminergic/glutamatergic pathway dysregulation, establishing an in vivo systems-level role.\",\n      \"evidence\": \"TARP γ-8 knockout mouse behavioral battery, synaptosomal proteomics in hippocampus and prefrontal cortex, pharmacological rescue with methylphenidate\",\n      \"pmids\": [\"36031768\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Whether conditional or region-specific knockout recapitulates the full behavioral syndrome not tested\",\n        \"Direct causality between proteomic changes and specific behavioral outputs not established\"\n      ]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Computational analysis of rare human CACNG8 variants predicted severe destabilization of postsynaptic AMPAR complexes and disrupted interactions with scaffolding partners, extending the loss-of-function mechanism to specific human mutations.\",\n      \"evidence\": \"Whole exome sequencing identifying stop-gain (p.Arg123Ter) and missense variants, followed by molecular docking, MM-PBSA/MM-GBSA, and molecular dynamics simulations of AMPAR–TARP γ-8–scaffold complexes\",\n      \"pmids\": [\"41127817\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Computational predictions of destabilization have not been experimentally validated by binding assays or electrophysiology\",\n        \"Clinical phenotypes of individuals carrying these rare variants not fully characterized\",\n        \"Whether these variants act through haploinsufficiency or dominant-negative mechanisms is unknown\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"A high-resolution experimental structure of the full TARP γ-8–AMPAR–scaffold ternary complex is needed to validate computational models and define the precise molecular interfaces disrupted by disease-associated mutations.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"No experimental atomic structure of the full TARP γ-8–AMPAR–PSD-95/CNIH ternary complex\",\n        \"Mechanism by which TARP γ-8 loss differentially affects glutamatergic versus dopaminergic circuits is unresolved\",\n        \"Whether CACNG8 variants contribute to human ADHD or other neurodevelopmental disorders through Mendelian or complex-trait mechanisms is undetermined\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [0, 2, 3]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [0, 2, 3]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-112316\", \"supporting_discovery_ids\": [0, 1, 2]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [1, 2]}\n    ],\n    \"complexes\": [\n      \"AMPA receptor complex\"\n    ],\n    \"partners\": [\n      \"GRIA1\",\n      \"GRIA2\",\n      \"PSD93\",\n      \"PSD95\",\n      \"CNIH2\",\n      \"CNIH3\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}