{"gene":"RIC8B","run_date":"2026-04-28T19:45:45","timeline":{"discoveries":[{"year":2005,"finding":"Ric-8B interacts with Gαolf (identified by yeast two-hybrid) and potentiates Gαolf-dependent cAMP accumulation in HEK293 cells, acting as a guanine nucleotide exchange factor (GEF) for Gαolf to amplify olfactory signal transduction.","method":"Yeast two-hybrid, cAMP accumulation assay in HEK293 cells","journal":"The Journal of neuroscience","confidence":"Medium","confidence_rationale":"Tier 2 — yeast two-hybrid plus functional cAMP assay, single lab","pmids":["15829631"],"is_preprint":false},{"year":2006,"finding":"Ric-8B promotes functional heterologous expression of odorant receptors (ORs) on the cell surface and enhances accumulation of Gαolf at the cell periphery, indicating it promotes OR-Gαolf coupling.","method":"Heterologous cell expression assay, immunofluorescence localization","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 — functional OR expression assay with localization data, single lab","pmids":["16754875"],"is_preprint":false},{"year":2008,"finding":"Ric-8B interacts with Gγ13 (in addition to Gαolf) and co-localizes with Gαolf, Gβ1, and Gγ13 in the cilia of olfactory sensory neurons; interaction with Gαolf is nucleotide-dependent, consistent with GEF activity.","method":"Co-immunoprecipitation, immunofluorescence localization, nucleotide-dependent binding assay","journal":"Molecular and cellular neurosciences","confidence":"Medium","confidence_rationale":"Tier 2 — reciprocal co-IP plus localization, single lab","pmids":["18462949"],"is_preprint":false},{"year":2010,"finding":"Ric-8B stabilizes Gαs protein by inhibiting its ubiquitination; Ric-8B binding to Gαs prevents ubiquitin-proteasome-mediated degradation, and Ric-8B splicing variants defective for Gαs binding fail to inhibit ubiquitination.","method":"Overexpression/knockdown, ubiquitination assay, co-immunoprecipitation with Gαs-binding-deficient mutants","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 — biochemical ubiquitination assay plus mutagenesis, single lab","pmids":["20133939"],"is_preprint":false},{"year":2011,"finding":"Ric-8B is a GEF for Gαs-class subunits: purified Ric-8BFL stimulates GTPγS binding to Gαs, Gαq, Gα13, and Gαolf; catalysis is GTP-dependent with Ric-8B binding nucleotide-free Gαs tightly and releasing free Gαs-GTP upon GTP binding.","method":"In vitro GEF assay (GTPγS binding), Michaelis-Menten kinetics, purified recombinant proteins","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 — rigorous in vitro biochemical reconstitution with kinetic analysis of purified proteins","pmids":["21467038"],"is_preprint":false},{"year":2011,"finding":"Ric-8B functions as a molecular chaperone for nascent Gα subunits: deletion of Ric-8B in mouse ES cells substantially reduces Gαs protein levels without affecting mRNA, reduces Gαs plasma membrane residence, and accelerates Gαs degradation, consistent with a chaperone role in membrane association of nascent Gαs.","method":"Knockout ES cells, quantitative western blot, mRNA analysis, subcellular fractionation, pulse-chase degradation assay","journal":"Science signaling","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods in knockout cells, replicated across Ric-8A and Ric-8B isoforms","pmids":["22114146"],"is_preprint":false},{"year":2013,"finding":"The molecular chaperoning function of Ric-8 is to fold nascent Gα subunits: Ric-8A depletion from rabbit reticulocyte lysate prevents proper folding of Gαi, Gαq, and Gα13 (assessed by trypsin protection), and in wheat germ extract (lacking Ric-8), Gαq is produced as an aggregate; Ric-8A supplementation allows formation of a folded ~100 kDa Ric-8A:Gαq heterodimer that releases Gαq-GTP upon GTP addition.","method":"Cell-free translation system, immunodepletion, limited trypsinolysis protection assay, gel filtration, reconstitution with recombinant Ric-8A","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 1 — reconstitution in cell-free system plus mutagenic complementation, multiple Gα substrates tested","pmids":["23431197"],"is_preprint":false},{"year":2013,"finding":"Ric-8B stabilizes Gαs against Gq-signaling-induced ubiquitination in cardiac myocytes; Gαq competes with Gαs for binding to Ric-8B in vitro, and co-expression of Ric-8B cancels Gαq-induced Gαs ubiquitination and rescues cAMP accumulation.","method":"Co-immunoprecipitation, ubiquitination assay in neonatal cardiomyocytes, cAMP accumulation assay","journal":"Genes to cells","confidence":"Medium","confidence_rationale":"Tier 2 — biochemical competition assay plus functional rescue, single lab","pmids":["24134321"],"is_preprint":false},{"year":2017,"finding":"Conditional deletion of Ric-8b specifically in olfactory sensory neurons (OMP-Cre × Ric-8b floxed mice) abolishes Gαolf protein expression in the olfactory epithelium, reduces the mature olfactory sensory neuron layer, increases neuronal cell death, and causes olfactory behavioral impairment.","method":"Tissue-specific knockout mouse, immunohistochemistry, cell death assay, behavioral olfaction test","journal":"The Journal of neuroscience","confidence":"High","confidence_rationale":"Tier 2 — clean conditional KO with defined molecular phenotype (loss of Gαolf) and functional behavioral outcome, multiple readouts","pmids":["29118104"],"is_preprint":false},{"year":2020,"finding":"Ric-8B is required for mTORC2 activity: Ric-8B hypomorphic mutant embryos show reduced phosphorylation of Akt at Ser473 (mTORC2 substrate), and siRNA knockdown of Ric-8B in cultured cells similarly reduces Akt Ser473 phosphorylation.","method":"Hypomorphic mouse model, western blot for Akt phosphorylation, siRNA knockdown in cell lines","journal":"PLoS genetics","confidence":"Medium","confidence_rationale":"Tier 2 — genetic and siRNA evidence converge on mTORC2 link, single lab, mechanism upstream of mTORC2 not fully resolved","pmids":["32392211"],"is_preprint":false},{"year":2023,"finding":"Cryo-EM structures of Ric-8B in complex with Gαs and Gαolf reveal isoform specificity: Ric-8B accommodates an extended loop unique to Gαs/olf within its concave α-helical repeat pocket via contacts at the Gα C-terminal α5 helix, and cell-based Gαolf folding assays confirm the C-terminal region of Gα is required for Ric-8B binding specificity.","method":"Cryo-EM structure determination, thermal stability assays, cell-based Gαolf folding assay","journal":"Structure","confidence":"High","confidence_rationale":"Tier 1 — cryo-EM structures plus functional validation by cell-based and biophysical assays","pmids":["36931277"],"is_preprint":false},{"year":2024,"finding":"Pathogenic GNAO1 (Gαo) encephalopathy mutants massively gain neomorphic interaction with Ric-8B (normally responsible only for Gαs/olf), relocalizing Ric-8B from cytoplasm to Golgi; the strength of the Gαo-Ric-8B interaction correlates with disease severity, indicating Ric-8B sequestration contributes to disease dominance by imbalancing neuronal G protein networks.","method":"Co-immunoprecipitation, subcellular localization imaging, correlation of interaction strength with clinical severity across >80 mutants","journal":"The Journal of clinical investigation","confidence":"High","confidence_rationale":"Tier 2 — extensive characterization of many mutants with orthogonal methods (co-IP, localization, GTP assays), strong correlative functional evidence","pmids":["38874642"],"is_preprint":false},{"year":2024,"finding":"Conditional cardiac deletion of Ric-8b in adult mice causes severe loss of contractile function, fibrosis, cardiomyocyte apoptosis, and loss of L-type calcium channel activation via the β-adrenergic/Gαs pathway; FRET assays show Ric-8b selectively interacts with Gαs in cardiomyocytes, and conditional Gαs deletion produces a comparable cardiac phenotype.","method":"Conditional cardiac knockout mouse (tamoxifen-inducible), echocardiography, histology, RNA-seq, phosphoproteomics, FRET-based interaction assay, epistasis with Gnas conditional KO","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal in vivo and cell-based methods, genetic epistasis with Gnas KO, strong phenotypic readouts","pmids":["38879012"],"is_preprint":false},{"year":2026,"finding":"RIC8B (and RIC8A) are required for ciliogenesis in human RPE-1 cells; in C. elegans, RIC-8 localizes to the inversin compartment (InvC) of cilia via intraflagellar transport and the RVxP motif, requiring an intact transition zone, and modulates chemosensory responses in ASH neurons.","method":"siRNA knockdown in RPE-1 cells, live imaging, mutagenesis of ciliary targeting motifs, behavioral chemosensory assays in C. elegans","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 — clean KO with defined cellular phenotype in human cells, mechanistic targeting dissected by mutagenesis; preprint","pmids":["41727026"],"is_preprint":true},{"year":2026,"finding":"RIC8B variant 4 (v4), which lacks the C-terminal cradle loop helix (CLH) domain, suppresses odorant-induced cAMP production (dominant-negative effect), while v1 (full-length) supports OR responses; AlphaFold3 modeling indicates v1 forms hydrogen bonds with Gαs via the CLH domain that v4 cannot establish.","method":"Odorant-induced cAMP functional assay in HEK293T cells, AlphaFold3 structure prediction, splice variant comparison","journal":"Bioscience, biotechnology, and biochemistry","confidence":"Low","confidence_rationale":"Tier 3 — functional cell assay with structural prediction, single lab, dominant-negative mechanism inferred by modeling","pmids":["41665873"],"is_preprint":false}],"current_model":"RIC8B is a molecular chaperone and non-receptor guanine nucleotide exchange factor (GEF) that acts on Gαs and Gαolf subunits: it folds nascent Gα subunits co-translationally (forming a transient nucleotide-free Ric-8B·Gα intermediate resolved by GTP binding), stabilizes Gαs by blocking ubiquitin-proteasome-mediated degradation, promotes plasma membrane/ciliary localization of Gαs/olf, and is essential in vivo for olfactory sensory neuron Gαolf expression and cardiac β-adrenergic/Gαs contractile signaling; structural studies reveal that isoform specificity toward Gαs/olf over Gαi-class subunits is conferred by contacts between Ric-8B's α-helical repeat concave pocket and the extended loop and C-terminal α5 helix unique to Gαs/olf."},"narrative":{"teleology":[{"year":2005,"claim":"The initial discovery that Ric-8B physically interacts with Gαolf and potentiates Gαolf-mediated cAMP signaling established it as a candidate GEF in olfactory transduction, answering whether there was a non-receptor activator of Gαolf.","evidence":"Yeast two-hybrid screen and cAMP accumulation assay in HEK293 cells","pmids":["15829631"],"confidence":"Medium","gaps":["GEF activity not demonstrated with purified proteins","no in vivo evidence of olfactory function","interaction domain mapping not performed"]},{"year":2006,"claim":"Demonstration that Ric-8B promotes odorant receptor surface expression and Gαolf peripheral accumulation revealed it acts upstream of receptor–G protein coupling, not merely as a signal amplifier.","evidence":"Heterologous OR expression assay and immunofluorescence in cultured cells","pmids":["16754875"],"confidence":"Medium","gaps":["mechanism of OR surface trafficking promotion unclear","in vivo relevance not tested"]},{"year":2008,"claim":"Finding that Ric-8B co-localizes with Gαolf in olfactory cilia and also interacts with Gγ13 extended its functional context to the ciliary signaling compartment and suggested roles beyond Gα alone.","evidence":"Co-immunoprecipitation, immunofluorescence in olfactory epithelium, nucleotide-dependent binding assays","pmids":["18462949"],"confidence":"Medium","gaps":["functional significance of Gγ13 interaction not established","whether Ric-8B is required for ciliary targeting not tested"]},{"year":2010,"claim":"The discovery that Ric-8B blocks Gαs ubiquitination and proteasomal degradation established a protein-stabilization function independent of catalytic GEF activity, answering how Gα protein levels are maintained.","evidence":"Ubiquitination assays and co-IP with splicing-defective Gαs-binding mutants in overexpression/knockdown systems","pmids":["20133939"],"confidence":"Medium","gaps":["identity of the E3 ligase targeting Gαs unknown","whether stabilization and GEF functions are separable in vivo unclear"]},{"year":2011,"claim":"Rigorous biochemical reconstitution confirmed Ric-8B is a bona fide GEF for Gαs-class subunits, forming a tight nucleotide-free complex that resolves upon GTP binding, while knockout ES cell studies showed Ric-8B is required for Gαs protein stability and membrane targeting in a chaperone-like capacity.","evidence":"In vitro GEF assay with purified proteins and Michaelis-Menten kinetics; Ric-8B-null ES cells with western blot, subcellular fractionation, and pulse-chase","pmids":["21467038","22114146"],"confidence":"High","gaps":["whether GEF and chaperone functions are mechanistically identical or separable remained open","structural basis of Gαs specificity not resolved"]},{"year":2013,"claim":"Cell-free translation reconstitution demonstrated that Ric-8 family members fold nascent Gα subunits co-translationally — without Ric-8, Gα aggregates — resolving the question of whether Ric-8 acts as a classical chaperone or merely a post-translational GEF.","evidence":"Immunodepletion from reticulocyte lysate, wheat germ cell-free translation, limited proteolysis, gel filtration with recombinant Ric-8A complementation","pmids":["23431197"],"confidence":"High","gaps":["demonstrated for Ric-8A and Gαi/q substrates; direct reconstitution of Ric-8B chaperone activity for Gαs not performed in this study","structural mechanism of co-translational folding unknown"]},{"year":2013,"claim":"Competition between Gαq and Gαs for Ric-8B binding in cardiomyocytes, where Ric-8B rescues Gαq-induced Gαs ubiquitination, showed that G protein homeostasis depends on a finite pool of Ric-8B acting as a limiting chaperone.","evidence":"Co-IP competition assay and ubiquitination rescue in neonatal cardiomyocytes","pmids":["24134321"],"confidence":"Medium","gaps":["stoichiometry of endogenous Ric-8B relative to Gα pools not quantified","in vivo cardiac relevance not tested at this point"]},{"year":2017,"claim":"Conditional knockout of Ric-8B in olfactory neurons abolished Gαolf protein, reduced the mature neuron layer, and impaired olfaction in vivo, providing definitive genetic proof that Ric-8B is the essential chaperone for Gαolf in the olfactory system.","evidence":"OMP-Cre × Ric-8b floxed conditional KO mice, immunohistochemistry, cell death assay, behavioral olfactory testing","pmids":["29118104"],"confidence":"High","gaps":["whether residual olfactory signaling uses alternative pathways not resolved","temporal requirement during development vs. maintenance not dissected"]},{"year":2020,"claim":"The finding that Ric-8B hypomorphic embryos and siRNA-treated cells show reduced mTORC2-dependent Akt phosphorylation extended Ric-8B function beyond classical Gα chaperoning, though the mechanistic link to mTORC2 remains incompletely defined.","evidence":"Ric-8B hypomorphic mouse embryos and siRNA knockdown with western blot for pAkt-Ser473","pmids":["32392211"],"confidence":"Medium","gaps":["whether effect on mTORC2 is direct or mediated through Gαs signaling not resolved","no biochemical interaction between Ric-8B and mTORC2 components demonstrated"]},{"year":2023,"claim":"Cryo-EM structures of Ric-8B bound to Gαs and Gαolf revealed how the α-helical repeat concave pocket accommodates the Gαs/olf-specific extended loop and α5 helix, answering the long-standing question of what determines Ric-8B isoform selectivity over Gαi-class subunits.","evidence":"Cryo-EM structure determination, thermal stability assays, cell-based Gαolf folding assays with Gα chimeras","pmids":["36931277"],"confidence":"High","gaps":["how phosphorylation of Ric-8B modulates the interaction is not structurally resolved","transition-state intermediates during folding not captured"]},{"year":2024,"claim":"Neomorphic gain of interaction between pathogenic GNAO1 mutants and Ric-8B, sequestering it to the Golgi, established a disease mechanism where Ric-8B titration disrupts neuronal G protein homeostasis proportional to clinical severity.","evidence":"Co-IP, subcellular localization imaging, and correlation of interaction strength with clinical severity across >80 GNAO1 mutants","pmids":["38874642"],"confidence":"High","gaps":["whether Ric-8B overexpression can rescue GNAO1 encephalopathy phenotype not tested","contribution of Ric-8B sequestration vs. Gαo gain-of-function not fully disentangled"]},{"year":2024,"claim":"Cardiac-specific deletion of Ric-8B in adult mice produced severe contractile failure, fibrosis, and loss of L-type calcium channel β-adrenergic activation, phenocopied by Gαs conditional deletion, demonstrating Ric-8B is the essential Gαs chaperone in the heart.","evidence":"Tamoxifen-inducible cardiac Ric-8B KO, echocardiography, histology, RNA-seq, phosphoproteomics, FRET interaction assay, genetic epistasis with Gnas KO","pmids":["38879012"],"confidence":"High","gaps":["whether Ric-8B has Gαs-independent cardiac functions not excluded","potential compensatory upregulation of Ric-8A not examined"]},{"year":null,"claim":"Key unresolved questions include: how Ric-8B co-translational folding is coordinated with ribosomal machinery, whether GEF and chaperone activities can be genetically separated in vivo, the identity of the E3 ubiquitin ligase opposing Ric-8B's stabilization of Gαs, the direct mechanism linking Ric-8B to mTORC2 signaling, and whether Ric-8B has essential roles in ciliogenesis beyond Gα chaperoning.","evidence":"","pmids":[],"confidence":"Low","gaps":["structural intermediates of co-translational Gα folding not captured","GEF vs. chaperone separation not achieved in vivo","E3 ligase for Gαs unknown","direct vs. indirect link to mTORC2 unresolved"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[0,4]},{"term_id":"GO:0044183","term_label":"protein folding chaperone","supporting_discovery_ids":[5,6]}],"localization":[{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[5,11]},{"term_id":"GO:0005929","term_label":"cilium","supporting_discovery_ids":[2]},{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[1,5]}],"pathway":[{"term_id":"R-HSA-392499","term_label":"Metabolism of proteins","supporting_discovery_ids":[3,5,6]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0,1,4,12]}],"complexes":[],"partners":["GNAL","GNAS","GNG13","GNAO1","GNAQ"],"other_free_text":[]},"mechanistic_narrative":"RIC8B is a molecular chaperone and guanine nucleotide exchange factor (GEF) for Gαs-class heterotrimeric G protein α-subunits (Gαs, Gαolf) that folds nascent Gα subunits co-translationally, stabilizes them against ubiquitin-proteasome-mediated degradation, and promotes their plasma membrane and ciliary localization [PMID:21467038, PMID:22114146, PMID:20133939]. Cryo-EM structures show that isoform specificity toward Gαs/olf is conferred by contacts between Ric-8B's concave α-helical repeat pocket and an extended loop and C-terminal α5 helix unique to Gαs/olf [PMID:36931277]. Conditional deletion of Ric-8B in olfactory sensory neurons abolishes Gαolf expression and impairs olfaction, while cardiac-specific deletion causes severe contractile dysfunction through loss of β-adrenergic/Gαs signaling [PMID:29118104, PMID:38879012]. Pathogenic GNAO1 encephalopathy mutations confer neomorphic gain of interaction with Ric-8B, sequestering it from its normal Gαs/olf substrates and contributing to disease severity [PMID:38874642]."},"prefetch_data":{"uniprot":{"accession":"Q9NVN3","full_name":"Chaperone Ric-8B","aliases":["Brain synembryn","hSyn","Synembryn-B"],"length_aa":520,"mass_kda":58.8,"function":"Chaperone that specifically binds and folds nascent G(s) G-alpha proteins (GNAS and GNAL) prior to G protein heterotrimer formation, promoting their association with the plasma membrane (By similarity). Also acts as a guanine nucleotide exchange factor (GEF) for G(s) proteins by stimulating exchange of bound GDP for free GTP (By similarity). Acts as an important component for odorant signal transduction by mediating GNAL (G(olf)-alpha) folding, thereby promoting-dependent cAMP accumulation in olfactory sensory neurons (By similarity)","subcellular_location":"Cytoplasm, cell cortex","url":"https://www.uniprot.org/uniprotkb/Q9NVN3/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/RIC8B","classification":"Not Classified","n_dependent_lines":0,"n_total_lines":1208,"dependency_fraction":0.0},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/RIC8B","total_profiled":1310},"omim":[{"mim_id":"609147","title":"RIC8 GUANINE NUCLEOTIDE EXCHANGE FACTOR B; RIC8B","url":"https://www.omim.org/entry/609147"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Cytosol","reliability":"Supported"},{"location":"Plasma membrane","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/RIC8B"},"hgnc":{"alias_symbol":["FLJ10620","hSyn","RIC8"],"prev_symbol":[]},"alphafold":{"accession":"Q9NVN3","domains":[{"cath_id":"1.25.10","chopping":"1-138","consensus_level":"medium","plddt":92.6964,"start":1,"end":138},{"cath_id":"-","chopping":"297-312_320-480","consensus_level":"medium","plddt":86.3685,"start":297,"end":480}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9NVN3","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9NVN3-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9NVN3-F1-predicted_aligned_error_v6.png","plddt_mean":86.38},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=RIC8B","jax_strain_url":"https://www.jax.org/strain/search?query=RIC8B"},"sequence":{"accession":"Q9NVN3","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9NVN3.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9NVN3/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9NVN3"}},"corpus_meta":[{"pmid":"15479639","id":"PMC_15479639","title":"RIC-8 is required for GPR-1/2-dependent Galpha function during asymmetric division of C. elegans embryos.","date":"2004","source":"Cell","url":"https://pubmed.ncbi.nlm.nih.gov/15479639","citation_count":161,"is_preprint":false},{"pmid":"10985349","id":"PMC_10985349","title":"RIC-8 (Synembryn): a novel conserved protein that is required for G(q)alpha signaling in the C. elegans nervous system.","date":"2000","source":"Neuron","url":"https://pubmed.ncbi.nlm.nih.gov/10985349","citation_count":118,"is_preprint":false},{"pmid":"16228010","id":"PMC_16228010","title":"Drosophila Ric-8 regulates Galphai cortical localization to promote Galphai-dependent planar orientation of the mitotic spindle during asymmetric cell division.","date":"2005","source":"Nature cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/16228010","citation_count":114,"is_preprint":false},{"pmid":"11102364","id":"PMC_11102364","title":"A role for RIC-8 (Synembryn) and GOA-1 (G(o)alpha) in regulating a subset of centrosome movements during early embryogenesis in Caenorhabditis elegans.","date":"2000","source":"Genetics","url":"https://pubmed.ncbi.nlm.nih.gov/11102364","citation_count":106,"is_preprint":false},{"pmid":"16228012","id":"PMC_16228012","title":"Ric-8 controls Drosophila neural progenitor asymmetric division by regulating heterotrimeric G proteins.","date":"2005","source":"Nature cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/16228012","citation_count":106,"is_preprint":false},{"pmid":"22114146","id":"PMC_22114146","title":"Ric-8 proteins are molecular chaperones that direct nascent G protein α subunit membrane association.","date":"2011","source":"Science signaling","url":"https://pubmed.ncbi.nlm.nih.gov/22114146","citation_count":104,"is_preprint":false},{"pmid":"15489510","id":"PMC_15489510","title":"Mutations that rescue the paralysis of Caenorhabditis elegans ric-8 (synembryn) mutants activate the G alpha(s) pathway and define a third major branch of the synaptic signaling 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\"Medium\",\n      \"confidence_rationale\": \"Tier 2 — yeast two-hybrid plus functional cAMP assay, single lab\",\n      \"pmids\": [\"15829631\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"Ric-8B promotes functional heterologous expression of odorant receptors (ORs) on the cell surface and enhances accumulation of Gαolf at the cell periphery, indicating it promotes OR-Gαolf coupling.\",\n      \"method\": \"Heterologous cell expression assay, immunofluorescence localization\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — functional OR expression assay with localization data, single lab\",\n      \"pmids\": [\"16754875\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Ric-8B interacts with Gγ13 (in addition to Gαolf) and co-localizes with Gαolf, Gβ1, and Gγ13 in the cilia of olfactory sensory neurons; interaction with Gαolf is nucleotide-dependent, consistent with GEF activity.\",\n      \"method\": \"Co-immunoprecipitation, immunofluorescence localization, nucleotide-dependent binding assay\",\n      \"journal\": \"Molecular and cellular neurosciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal co-IP plus localization, single lab\",\n      \"pmids\": [\"18462949\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Ric-8B stabilizes Gαs protein by inhibiting its ubiquitination; Ric-8B binding to Gαs prevents ubiquitin-proteasome-mediated degradation, and Ric-8B splicing variants defective for Gαs binding fail to inhibit ubiquitination.\",\n      \"method\": \"Overexpression/knockdown, ubiquitination assay, co-immunoprecipitation with Gαs-binding-deficient mutants\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — biochemical ubiquitination assay plus mutagenesis, single lab\",\n      \"pmids\": [\"20133939\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Ric-8B is a GEF for Gαs-class subunits: purified Ric-8BFL stimulates GTPγS binding to Gαs, Gαq, Gα13, and Gαolf; catalysis is GTP-dependent with Ric-8B binding nucleotide-free Gαs tightly and releasing free Gαs-GTP upon GTP binding.\",\n      \"method\": \"In vitro GEF assay (GTPγS binding), Michaelis-Menten kinetics, purified recombinant proteins\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — rigorous in vitro biochemical reconstitution with kinetic analysis of purified proteins\",\n      \"pmids\": [\"21467038\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Ric-8B functions as a molecular chaperone for nascent Gα subunits: deletion of Ric-8B in mouse ES cells substantially reduces Gαs protein levels without affecting mRNA, reduces Gαs plasma membrane residence, and accelerates Gαs degradation, consistent with a chaperone role in membrane association of nascent Gαs.\",\n      \"method\": \"Knockout ES cells, quantitative western blot, mRNA analysis, subcellular fractionation, pulse-chase degradation assay\",\n      \"journal\": \"Science signaling\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods in knockout cells, replicated across Ric-8A and Ric-8B isoforms\",\n      \"pmids\": [\"22114146\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"The molecular chaperoning function of Ric-8 is to fold nascent Gα subunits: Ric-8A depletion from rabbit reticulocyte lysate prevents proper folding of Gαi, Gαq, and Gα13 (assessed by trypsin protection), and in wheat germ extract (lacking Ric-8), Gαq is produced as an aggregate; Ric-8A supplementation allows formation of a folded ~100 kDa Ric-8A:Gαq heterodimer that releases Gαq-GTP upon GTP addition.\",\n      \"method\": \"Cell-free translation system, immunodepletion, limited trypsinolysis protection assay, gel filtration, reconstitution with recombinant Ric-8A\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — reconstitution in cell-free system plus mutagenic complementation, multiple Gα substrates tested\",\n      \"pmids\": [\"23431197\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Ric-8B stabilizes Gαs against Gq-signaling-induced ubiquitination in cardiac myocytes; Gαq competes with Gαs for binding to Ric-8B in vitro, and co-expression of Ric-8B cancels Gαq-induced Gαs ubiquitination and rescues cAMP accumulation.\",\n      \"method\": \"Co-immunoprecipitation, ubiquitination assay in neonatal cardiomyocytes, cAMP accumulation assay\",\n      \"journal\": \"Genes to cells\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — biochemical competition assay plus functional rescue, single lab\",\n      \"pmids\": [\"24134321\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Conditional deletion of Ric-8b specifically in olfactory sensory neurons (OMP-Cre × Ric-8b floxed mice) abolishes Gαolf protein expression in the olfactory epithelium, reduces the mature olfactory sensory neuron layer, increases neuronal cell death, and causes olfactory behavioral impairment.\",\n      \"method\": \"Tissue-specific knockout mouse, immunohistochemistry, cell death assay, behavioral olfaction test\",\n      \"journal\": \"The Journal of neuroscience\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — clean conditional KO with defined molecular phenotype (loss of Gαolf) and functional behavioral outcome, multiple readouts\",\n      \"pmids\": [\"29118104\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Ric-8B is required for mTORC2 activity: Ric-8B hypomorphic mutant embryos show reduced phosphorylation of Akt at Ser473 (mTORC2 substrate), and siRNA knockdown of Ric-8B in cultured cells similarly reduces Akt Ser473 phosphorylation.\",\n      \"method\": \"Hypomorphic mouse model, western blot for Akt phosphorylation, siRNA knockdown in cell lines\",\n      \"journal\": \"PLoS genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — genetic and siRNA evidence converge on mTORC2 link, single lab, mechanism upstream of mTORC2 not fully resolved\",\n      \"pmids\": [\"32392211\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Cryo-EM structures of Ric-8B in complex with Gαs and Gαolf reveal isoform specificity: Ric-8B accommodates an extended loop unique to Gαs/olf within its concave α-helical repeat pocket via contacts at the Gα C-terminal α5 helix, and cell-based Gαolf folding assays confirm the C-terminal region of Gα is required for Ric-8B binding specificity.\",\n      \"method\": \"Cryo-EM structure determination, thermal stability assays, cell-based Gαolf folding assay\",\n      \"journal\": \"Structure\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — cryo-EM structures plus functional validation by cell-based and biophysical assays\",\n      \"pmids\": [\"36931277\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Pathogenic GNAO1 (Gαo) encephalopathy mutants massively gain neomorphic interaction with Ric-8B (normally responsible only for Gαs/olf), relocalizing Ric-8B from cytoplasm to Golgi; the strength of the Gαo-Ric-8B interaction correlates with disease severity, indicating Ric-8B sequestration contributes to disease dominance by imbalancing neuronal G protein networks.\",\n      \"method\": \"Co-immunoprecipitation, subcellular localization imaging, correlation of interaction strength with clinical severity across >80 mutants\",\n      \"journal\": \"The Journal of clinical investigation\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — extensive characterization of many mutants with orthogonal methods (co-IP, localization, GTP assays), strong correlative functional evidence\",\n      \"pmids\": [\"38874642\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Conditional cardiac deletion of Ric-8b in adult mice causes severe loss of contractile function, fibrosis, cardiomyocyte apoptosis, and loss of L-type calcium channel activation via the β-adrenergic/Gαs pathway; FRET assays show Ric-8b selectively interacts with Gαs in cardiomyocytes, and conditional Gαs deletion produces a comparable cardiac phenotype.\",\n      \"method\": \"Conditional cardiac knockout mouse (tamoxifen-inducible), echocardiography, histology, RNA-seq, phosphoproteomics, FRET-based interaction assay, epistasis with Gnas conditional KO\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal in vivo and cell-based methods, genetic epistasis with Gnas KO, strong phenotypic readouts\",\n      \"pmids\": [\"38879012\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"RIC8B (and RIC8A) are required for ciliogenesis in human RPE-1 cells; in C. elegans, RIC-8 localizes to the inversin compartment (InvC) of cilia via intraflagellar transport and the RVxP motif, requiring an intact transition zone, and modulates chemosensory responses in ASH neurons.\",\n      \"method\": \"siRNA knockdown in RPE-1 cells, live imaging, mutagenesis of ciliary targeting motifs, behavioral chemosensory assays in C. elegans\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — clean KO with defined cellular phenotype in human cells, mechanistic targeting dissected by mutagenesis; preprint\",\n      \"pmids\": [\"41727026\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"RIC8B variant 4 (v4), which lacks the C-terminal cradle loop helix (CLH) domain, suppresses odorant-induced cAMP production (dominant-negative effect), while v1 (full-length) supports OR responses; AlphaFold3 modeling indicates v1 forms hydrogen bonds with Gαs via the CLH domain that v4 cannot establish.\",\n      \"method\": \"Odorant-induced cAMP functional assay in HEK293T cells, AlphaFold3 structure prediction, splice variant comparison\",\n      \"journal\": \"Bioscience, biotechnology, and biochemistry\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 — functional cell assay with structural prediction, single lab, dominant-negative mechanism inferred by modeling\",\n      \"pmids\": [\"41665873\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"RIC8B is a molecular chaperone and non-receptor guanine nucleotide exchange factor (GEF) that acts on Gαs and Gαolf subunits: it folds nascent Gα subunits co-translationally (forming a transient nucleotide-free Ric-8B·Gα intermediate resolved by GTP binding), stabilizes Gαs by blocking ubiquitin-proteasome-mediated degradation, promotes plasma membrane/ciliary localization of Gαs/olf, and is essential in vivo for olfactory sensory neuron Gαolf expression and cardiac β-adrenergic/Gαs contractile signaling; structural studies reveal that isoform specificity toward Gαs/olf over Gαi-class subunits is conferred by contacts between Ric-8B's α-helical repeat concave pocket and the extended loop and C-terminal α5 helix unique to Gαs/olf.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"RIC8B is a molecular chaperone and guanine nucleotide exchange factor (GEF) for Gαs-class heterotrimeric G protein α-subunits (Gαs, Gαolf) that folds nascent Gα subunits co-translationally, stabilizes them against ubiquitin-proteasome-mediated degradation, and promotes their plasma membrane and ciliary localization [PMID:21467038, PMID:22114146, PMID:20133939]. Cryo-EM structures show that isoform specificity toward Gαs/olf is conferred by contacts between Ric-8B's concave α-helical repeat pocket and an extended loop and C-terminal α5 helix unique to Gαs/olf [PMID:36931277]. Conditional deletion of Ric-8B in olfactory sensory neurons abolishes Gαolf expression and impairs olfaction, while cardiac-specific deletion causes severe contractile dysfunction through loss of β-adrenergic/Gαs signaling [PMID:29118104, PMID:38879012]. Pathogenic GNAO1 encephalopathy mutations confer neomorphic gain of interaction with Ric-8B, sequestering it from its normal Gαs/olf substrates and contributing to disease severity [PMID:38874642].\",\n  \"teleology\": [\n    {\n      \"year\": 2005,\n      \"claim\": \"The initial discovery that Ric-8B physically interacts with Gαolf and potentiates Gαolf-mediated cAMP signaling established it as a candidate GEF in olfactory transduction, answering whether there was a non-receptor activator of Gαolf.\",\n      \"evidence\": \"Yeast two-hybrid screen and cAMP accumulation assay in HEK293 cells\",\n      \"pmids\": [\"15829631\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"GEF activity not demonstrated with purified proteins\", \"no in vivo evidence of olfactory function\", \"interaction domain mapping not performed\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Demonstration that Ric-8B promotes odorant receptor surface expression and Gαolf peripheral accumulation revealed it acts upstream of receptor–G protein coupling, not merely as a signal amplifier.\",\n      \"evidence\": \"Heterologous OR expression assay and immunofluorescence in cultured cells\",\n      \"pmids\": [\"16754875\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"mechanism of OR surface trafficking promotion unclear\", \"in vivo relevance not tested\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Finding that Ric-8B co-localizes with Gαolf in olfactory cilia and also interacts with Gγ13 extended its functional context to the ciliary signaling compartment and suggested roles beyond Gα alone.\",\n      \"evidence\": \"Co-immunoprecipitation, immunofluorescence in olfactory epithelium, nucleotide-dependent binding assays\",\n      \"pmids\": [\"18462949\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"functional significance of Gγ13 interaction not established\", \"whether Ric-8B is required for ciliary targeting not tested\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"The discovery that Ric-8B blocks Gαs ubiquitination and proteasomal degradation established a protein-stabilization function independent of catalytic GEF activity, answering how Gα protein levels are maintained.\",\n      \"evidence\": \"Ubiquitination assays and co-IP with splicing-defective Gαs-binding mutants in overexpression/knockdown systems\",\n      \"pmids\": [\"20133939\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"identity of the E3 ligase targeting Gαs unknown\", \"whether stabilization and GEF functions are separable in vivo unclear\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Rigorous biochemical reconstitution confirmed Ric-8B is a bona fide GEF for Gαs-class subunits, forming a tight nucleotide-free complex that resolves upon GTP binding, while knockout ES cell studies showed Ric-8B is required for Gαs protein stability and membrane targeting in a chaperone-like capacity.\",\n      \"evidence\": \"In vitro GEF assay with purified proteins and Michaelis-Menten kinetics; Ric-8B-null ES cells with western blot, subcellular fractionation, and pulse-chase\",\n      \"pmids\": [\"21467038\", \"22114146\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"whether GEF and chaperone functions are mechanistically identical or separable remained open\", \"structural basis of Gαs specificity not resolved\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Cell-free translation reconstitution demonstrated that Ric-8 family members fold nascent Gα subunits co-translationally — without Ric-8, Gα aggregates — resolving the question of whether Ric-8 acts as a classical chaperone or merely a post-translational GEF.\",\n      \"evidence\": \"Immunodepletion from reticulocyte lysate, wheat germ cell-free translation, limited proteolysis, gel filtration with recombinant Ric-8A complementation\",\n      \"pmids\": [\"23431197\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"demonstrated for Ric-8A and Gαi/q substrates; direct reconstitution of Ric-8B chaperone activity for Gαs not performed in this study\", \"structural mechanism of co-translational folding unknown\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Competition between Gαq and Gαs for Ric-8B binding in cardiomyocytes, where Ric-8B rescues Gαq-induced Gαs ubiquitination, showed that G protein homeostasis depends on a finite pool of Ric-8B acting as a limiting chaperone.\",\n      \"evidence\": \"Co-IP competition assay and ubiquitination rescue in neonatal cardiomyocytes\",\n      \"pmids\": [\"24134321\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"stoichiometry of endogenous Ric-8B relative to Gα pools not quantified\", \"in vivo cardiac relevance not tested at this point\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Conditional knockout of Ric-8B in olfactory neurons abolished Gαolf protein, reduced the mature neuron layer, and impaired olfaction in vivo, providing definitive genetic proof that Ric-8B is the essential chaperone for Gαolf in the olfactory system.\",\n      \"evidence\": \"OMP-Cre × Ric-8b floxed conditional KO mice, immunohistochemistry, cell death assay, behavioral olfactory testing\",\n      \"pmids\": [\"29118104\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"whether residual olfactory signaling uses alternative pathways not resolved\", \"temporal requirement during development vs. maintenance not dissected\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"The finding that Ric-8B hypomorphic embryos and siRNA-treated cells show reduced mTORC2-dependent Akt phosphorylation extended Ric-8B function beyond classical Gα chaperoning, though the mechanistic link to mTORC2 remains incompletely defined.\",\n      \"evidence\": \"Ric-8B hypomorphic mouse embryos and siRNA knockdown with western blot for pAkt-Ser473\",\n      \"pmids\": [\"32392211\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"whether effect on mTORC2 is direct or mediated through Gαs signaling not resolved\", \"no biochemical interaction between Ric-8B and mTORC2 components demonstrated\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Cryo-EM structures of Ric-8B bound to Gαs and Gαolf revealed how the α-helical repeat concave pocket accommodates the Gαs/olf-specific extended loop and α5 helix, answering the long-standing question of what determines Ric-8B isoform selectivity over Gαi-class subunits.\",\n      \"evidence\": \"Cryo-EM structure determination, thermal stability assays, cell-based Gαolf folding assays with Gα chimeras\",\n      \"pmids\": [\"36931277\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"how phosphorylation of Ric-8B modulates the interaction is not structurally resolved\", \"transition-state intermediates during folding not captured\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Neomorphic gain of interaction between pathogenic GNAO1 mutants and Ric-8B, sequestering it to the Golgi, established a disease mechanism where Ric-8B titration disrupts neuronal G protein homeostasis proportional to clinical severity.\",\n      \"evidence\": \"Co-IP, subcellular localization imaging, and correlation of interaction strength with clinical severity across >80 GNAO1 mutants\",\n      \"pmids\": [\"38874642\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"whether Ric-8B overexpression can rescue GNAO1 encephalopathy phenotype not tested\", \"contribution of Ric-8B sequestration vs. Gαo gain-of-function not fully disentangled\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Cardiac-specific deletion of Ric-8B in adult mice produced severe contractile failure, fibrosis, and loss of L-type calcium channel β-adrenergic activation, phenocopied by Gαs conditional deletion, demonstrating Ric-8B is the essential Gαs chaperone in the heart.\",\n      \"evidence\": \"Tamoxifen-inducible cardiac Ric-8B KO, echocardiography, histology, RNA-seq, phosphoproteomics, FRET interaction assay, genetic epistasis with Gnas KO\",\n      \"pmids\": [\"38879012\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"whether Ric-8B has Gαs-independent cardiac functions not excluded\", \"potential compensatory upregulation of Ric-8A not examined\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"Key unresolved questions include: how Ric-8B co-translational folding is coordinated with ribosomal machinery, whether GEF and chaperone activities can be genetically separated in vivo, the identity of the E3 ubiquitin ligase opposing Ric-8B's stabilization of Gαs, the direct mechanism linking Ric-8B to mTORC2 signaling, and whether Ric-8B has essential roles in ciliogenesis beyond Gα chaperoning.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"structural intermediates of co-translational Gα folding not captured\", \"GEF vs. chaperone separation not achieved in vivo\", \"E3 ligase for Gαs unknown\", \"direct vs. indirect link to mTORC2 unresolved\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [0, 4]},\n      {\"term_id\": \"GO:0044183\", \"supporting_discovery_ids\": [5, 6]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [5, 11]},\n      {\"term_id\": \"GO:0005929\", \"supporting_discovery_ids\": [2]},\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [1, 5]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0162582\", \"supporting_discovery_ids\": [0, 1, 4, 12]},\n      {\"term_id\": \"R-HSA-392499\", \"supporting_discovery_ids\": [3, 5, 6]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 1, 4, 12]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"GNAL\", \"GNAS\", \"GNG13\", \"GNAO1\", \"GNAQ\"],\n    \"other_free_text\": []\n  }\n}\n```"}