{"gene":"UNC119","run_date":"2026-04-28T21:43:01","timeline":{"discoveries":[{"year":1995,"finding":"unc-119 is expressed throughout the C. elegans nervous system and is required for locomotion, feeding behavior, and chemosensation; the UNC-119 protein is predicted to be a novel protein with no similarity to other known proteins at that time.","method":"Genetic mapping, transgenic rescue, reporter gene (unc-119/lacZ fusion), phenotypic characterization","journal":"Genetics","confidence":"Medium","confidence_rationale":"Tier 2 — clean loss-of-function with defined neural phenotype and transgenic rescue, foundational paper","pmids":["8582641"],"is_preprint":false},{"year":1998,"finding":"HRG4 (UNC119) protein is localized specifically to the synaptic termini of rod and cone photoreceptors in the outer plexiform layer, on presynaptic membranes and cytoplasm, suggesting a function in photoreceptor neurotransmission.","method":"Immunofluorescence and electron microscopic immunolocalization, Western blot (retina-specific expression)","journal":"Investigative ophthalmology & visual science","confidence":"Medium","confidence_rationale":"Tier 2 — direct subcellular localization by EM and immunofluorescence in retinal tissue","pmids":["9538874"],"is_preprint":false},{"year":2000,"finding":"The conserved C-terminal domain of human HRG4/UNC119 is functionally required; expression of human or Drosophila UNC119 in C. elegans unc-119 mutants fully rescues the mutant phenotype, establishing functional conservation across metazoans.","method":"Transgenic rescue experiments in C. elegans with heterologous UNC119 constructs and domain deletions","journal":"Journal of neurogenetics","confidence":"Medium","confidence_rationale":"Tier 2 — domain-deletion transgenic rescue defines functional region","pmids":["10858820"],"is_preprint":false},{"year":2000,"finding":"A heterozygous premature termination mutation in HRG4 (UNC119) causes late-onset cone-rod dystrophy in a patient, and transgenic mice expressing the identical truncation mutation develop age-dependent retinal degeneration with defects consistent with photoreceptor synaptic transmission dysfunction (depressed b-wave, normal c-wave).","method":"Transgenic mouse model, ERG, funduscopy, histopathology","journal":"Investigative ophthalmology & visual science","confidence":"High","confidence_rationale":"Tier 2 — human mutation confirmed in transgenic model with defined functional phenotype","pmids":["11006213"],"is_preprint":false},{"year":2001,"finding":"UNC-119 acts cell-autonomously in neurons to suppress axon branching; in unc-119 mutants, motor neuron commissures develop supernumerary branches after development is complete, with secondary growth cones sprouting from existing axons, and this defect can be suppressed by post-embryonic UNC-119 expression.","method":"Live imaging of growth cone dynamics, genetic rescue with temporal control, loss-of-function analysis","journal":"Development (Cambridge, England)","confidence":"High","confidence_rationale":"Tier 2 — live imaging + temporal rescue establishes cell-autonomous role in axon stabilization","pmids":["11641230"],"is_preprint":false},{"year":2002,"finding":"UNC119 interacts with Src family tyrosine kinases (Lyn) via SH2 and SH3 domains and activates their catalytic activity; it also associates with the IL-5Rα receptor; UNC119 overexpression prolongs eosinophil survival by increasing Lyn activity.","method":"Yeast two-hybrid, co-immunoprecipitation, kinase activity assays, overexpression in eosinophils","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2–3 — yeast two-hybrid plus Co-IP plus kinase activity assay in primary cells","pmids":["12496276"],"is_preprint":false},{"year":2003,"finding":"HRG4 (UNC119) interacts with ARL2 (ADP-ribosylation factor-like protein 2); the interaction was identified by yeast two-hybrid and confirmed by co-immunoprecipitation and direct binding analysis; residues in HRG4 homologous to those in PDEδ that form the hydrophobic pocket are conserved, suggesting a similar binding mechanism.","method":"Yeast two-hybrid, co-immunoprecipitation, direct binding analysis, immunofluorescence co-localization","journal":"FEBS letters","confidence":"Medium","confidence_rationale":"Tier 3 — Co-IP and direct binding confirmed, but single lab","pmids":["12527357"],"is_preprint":false},{"year":2004,"finding":"UNC119 associates with CD3 and CD4 in T cells, activates Lck and Fyn kinases, and is essential for T cell activation; UNC119-deficient T cells have dramatically reduced Lck/Fyn activity, decreased IL-2 production, and impaired proliferation; reconstitution with UNC119 reverses these defects.","method":"Co-immunoprecipitation, kinase activity assays, UNC119-deficient T cells, reconstitution experiments","journal":"The Journal of experimental medicine","confidence":"High","confidence_rationale":"Tier 2 — Co-IP, kinase assays, KO/reconstitution with defined signaling phenotype","pmids":["14757743"],"is_preprint":false},{"year":2006,"finding":"The truncated HRG4 mutant protein exhibits approximately 3-fold greater affinity for ARL2 compared to wild-type HRG4, leading to sequestration of ARL2, reduced ANT-1 in photoreceptor synaptic mitochondria, mitochondrial dysfunction, cytochrome c release and caspase 3 activation within photoreceptor synapses, and ultimately apoptosis — establishing a novel synaptic degeneration pathway.","method":"Saturation binding analysis, Western blot, immunofluorescence, TUNEL, morphometric analysis in transgenic mouse model","journal":"Investigative ophthalmology & visual science","confidence":"High","confidence_rationale":"Tier 2 — saturation binding plus multiple downstream mechanistic readouts in vivo","pmids":["16565359"],"is_preprint":false},{"year":2006,"finding":"Knockout of HRG4 (MRG4) in mice causes a slowly progressive retinal degeneration distinct from the transgenic truncation model, with early dysfunction in the distal photoreceptor (inner/outer segments), revealing a second function for UNC119 outside the synapse.","method":"Gene targeting/knockout mouse, ERG, Western blot, immunofluorescence, EM, TUNEL","journal":"Experimental eye research","confidence":"High","confidence_rationale":"Tier 2 — clean KO with defined cellular phenotype and comparison to TG model establishing dual functionality","pmids":["17174953"],"is_preprint":false},{"year":2007,"finding":"UNC119 activates Fyn kinase and is required for TGF-β/PDGF-induced Fyn phosphorylation; UNC119 overexpression stimulates p38 MAPK (but not JNK), and p38 pathway activity downstream of UNC119 is required for α-SMA induction and myofibroblast differentiation; this mechanism requires Fyn as demonstrated by reconstitution in SYF cells.","method":"Co-precipitation, co-localization, kinase activity assays, siRNA knockdown, overexpression in SYF cells and human lung fibroblasts, p38 inhibitor experiments","journal":"Journal of immunology","confidence":"High","confidence_rationale":"Tier 2 — epistasis in SYF reconstitution plus multiple biochemical readouts","pmids":["17579091"],"is_preprint":false},{"year":2008,"finding":"Munc119/UNC119 is recruited to photoreceptor synaptic ribbons through direct interaction with the RIBEYE protein; the PrBP/delta homology domain of Munc119 is essential for binding to the NADH-binding region of the RIBEYE(B) domain; the RIBEYE-Munc119 interaction is independent of NADH binding.","method":"Five independent approaches: yeast two-hybrid, co-immunoprecipitation, direct binding assays, affinity chromatography, point mutant analysis (RE(B)E844Q)","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1–2 — five orthogonal methods including mutagenesis in a single study","pmids":["18664567"],"is_preprint":false},{"year":2008,"finding":"CaBP4 directly interacts with UNC119 at the photoreceptor synapse; reduction in UNC119 levels is observed in photoreceptor terminals of CaBP4-knockout mice, suggesting a functional relationship for neurotransmitter release.","method":"Affinity chromatography, yeast two-hybrid, co-immunoprecipitation, gel overlay assay, immunohistochemistry in CaBP4-KO mice","journal":"Investigative ophthalmology & visual science","confidence":"Medium","confidence_rationale":"Tier 2–3 — multiple binding assays plus in vivo KO evidence","pmids":["18296658"],"is_preprint":false},{"year":2009,"finding":"UNC119 interacts with dynamin and inhibits its GTPase activity; binding of UNC119 to dynamin decreases its association with amphiphysin; UNC119 overexpression inhibits clathrin- and caveolae-based endocytosis, while depletion increases endocytosis.","method":"Co-immunoprecipitation, GTPase activity assay, endocytosis assays (transferrin, FM4-64, albumin uptake), overexpression/knockdown","journal":"Cellular signalling","confidence":"Medium","confidence_rationale":"Tier 2–3 — Co-IP plus in vitro GTPase assay plus functional endocytosis readouts","pmids":["19781630"],"is_preprint":false},{"year":2009,"finding":"UNC119 interacts with Abl family kinases and inhibits their kinase activity, thereby inhibiting Crk phosphorylation and reducing Shigella cell invasion; UNC119 co-localizes with Crk and Shigella in infected cells.","method":"Co-immunoprecipitation, kinase activity assays, siRNA knockdown, in vivo mouse model of shigellosis","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2–3 — biochemical inhibition assay plus in vivo KD with functional phenotype","pmids":["19381274"],"is_preprint":false},{"year":2011,"finding":"UNC119 recognizes and tightly binds the acylated (myristoylated/lauroylated) N-terminus of the rod transducin α subunit (Gαt1) and C. elegans G proteins ODR-3 and GPA-13; the crystal structure of human UNC119 at 1.95 Å reveals an immunoglobulin-like β-sandwich fold with a hydrophobic cavity that buries the lipid chain; co-crystal structure with acylated Tα peptide at 2.0 Å shows the lipid buried deeply in the cavity; UNC119 binding to Tα-GTP inhibits GTPase activity, stabilizing a diffusible UNC119-Tα-GTP complex; UNC119 deletion causes G protein mislocalization in mouse and C. elegans.","method":"Crystal structure (1.95 Å and 2.0 Å co-crystal), isothermal titration calorimetry, pulldowns, UNC119 knockout mouse and C. elegans","journal":"Nature neuroscience","confidence":"High","confidence_rationale":"Tier 1 — crystal structures plus ITC plus in vivo KO, replicated findings","pmids":["21642972"],"is_preprint":false},{"year":2011,"finding":"Human UNC119 (HRG4) interaction with transducin (Gαt1) requires N-acylation but not the GTP-bound form; UNC119 binds myristoylated Gαt1 with much higher affinity than prenylated substrates; UNC119 can interact with Gαt1-GDP and heterotrimeric transducin, displacing Gβ1γ1 and facilitating solubilization of transducin from rod outer segment membranes; UNC119 inhibits rhodopsin-dependent Gt activation and inhibits Go activation by D2 dopamine receptor in cultured cells.","method":"Pulldown assays, GTPase activity assays, membrane solubilization assay, cell-based GPCR activation assay","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal biochemical assays establishing binding specificity and functional consequences","pmids":["21712387"],"is_preprint":false},{"year":2011,"finding":"UNC119 (specifically UNC119b) functions as a chaperone for myristoylated NPHP3, binding NPHP3 via its N-terminal 200 residues in a myristoylation-dependent manner; ARL3-GTP releases myristoylated cargo from UNC119b; ARL3, UNC119b, and the ARL3 GAP RP2 are all required for NPHP3 ciliary targeting; UNC119b myristoyl-binding activity is required for this targeting; conserved phenylalanines in a hydrophobic β-sandwich are essential for myristate binding.","method":"Proteomic approach, co-immunoprecipitation, directed mutagenesis of predicted structural residues, UNC119b knockdown in IMCD3 cells, C. elegans genetics","journal":"Genes & development","confidence":"High","confidence_rationale":"Tier 1–2 — structure-guided mutagenesis plus proteomic identification plus functional knockdown, replicated by multiple labs","pmids":["22085962"],"is_preprint":false},{"year":2012,"finding":"Crystal structures of Arl3 and Arl2 in complex with UNC119a show both bind with similar affinities, but only Arl3-GTP allosterically displaces myristoylated cargo by accelerating release by ~1000-fold; this is due to the N-terminal amphipathic helix of Arl3·GppNHp remaining surface-bound and inducing widening of the myristoyl binding pocket, opposite to the PDEδ mechanism.","method":"Crystal structures of Arl3/Arl2 complexes with UNC119a, dissociation kinetics, affinity measurements","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 1 — crystal structures plus kinetic measurements revealing molecular basis of Arl3 specificity","pmids":["22960633"],"is_preprint":false},{"year":2016,"finding":"Myristoylated ciliary cargo peptides (GNAT1, NPHP3, Cystin1) bind UNC119a and UNC119b with subnanomolar affinities, while non-ciliary Src peptide has low affinity; high-affinity cargo is exclusively released by Arl3·GppNHp but not Arl2; low-affinity cargo is released by both; crystal structure of myristoylated NPHP3 peptide with UNC119a identifies residues at +2/+3 positions as determinants of binding affinity; swapping these residues reverses affinities and causes mislocalization.","method":"X-ray crystal structure, ITC/affinity measurements, mutagenesis of cargo peptides, cellular localization assays","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 — crystal structure plus mutagenesis plus affinity measurements plus cellular validation","pmids":["27481943"],"is_preprint":false},{"year":2017,"finding":"UNC119 sequesters myristoylated Src family kinases (SFKs) from the cytoplasm, forming a soluble complex that enables diffusion to the recycling endosome, where localized Arl2/3 activity releases SFKs; this spatial cycle maintains SFK enrichment at the plasma membrane; UNC119 knockdown disrupts SFK plasma membrane localization and signaling activity.","method":"Live-cell imaging, FRAP, siRNA knockdown, quantitative fluorescence microscopy, biochemical fractionation","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 — direct live-cell localization experiments plus KD with defined signaling phenotype, multiple orthogonal approaches","pmids":["28740133"],"is_preprint":false},{"year":2017,"finding":"Squarunkin A, a small-molecule inhibitor, selectively inhibits UNC119A binding to a myristoylated Src N-terminal peptide with IC50 ~10 nM, binds UNC119 proteins in cell lysate, and interferes with Src kinase activation, demonstrating the druggability of the UNC119-cargo interaction.","method":"Biochemical binding assay (IC50 determination), cell lysate binding, Src kinase activity assay","journal":"Angewandte Chemie (International ed. in English)","confidence":"Medium","confidence_rationale":"Tier 2–3 — in vitro binding plus cell-based kinase assay with small-molecule tool","pmids":["28471079"],"is_preprint":false},{"year":2018,"finding":"UNC119 (UNC119A) interacts with RASSF6 tumor suppressor, promotes RASSF6-MDM2 interaction, and stabilizes p53, inducing apoptosis; UNC119 depletion impairs DNA repair after damage and results in polyploid cell generation.","method":"Immunoprecipitation, RNAi knockdown, cell biology assays (apoptosis, DNA damage repair, ploidy)","journal":"Cancer science","confidence":"Low","confidence_rationale":"Tier 3 — single Co-IP plus KD phenotype, single lab","pmids":["29931788"],"is_preprint":false},{"year":2019,"finding":"UNC119a plays a role in cytokinesis; lipidated stapled peptides derived from the Gnat1 UNC119-binding region bind UNC119a and induce accumulation of cytokinetic and binucleated cells upon cell treatment.","method":"Hydrocarbon peptide-stapling, cell-based assays (cytokinesis phenotype), binding assays","journal":"Chembiochem","confidence":"Low","confidence_rationale":"Tier 3 — pharmacological perturbation with phenotypic readout, no direct molecular mechanism established","pmids":["31680402"],"is_preprint":false},{"year":2020,"finding":"UNC119A interacts with the active form of KRAS (requiring C-terminal KRAS modification but not the hydrophobic pocket of UNC119A), promotes KRAS-RASSF6 interaction, enhances RASSF6-MDM2 binding, and induces apoptosis; UNC119A silencing promotes soft-agar colony formation, migration, and invasiveness in KRAS-mutated cancer cells.","method":"Immunoprecipitation, RNAi gene silencing, quantitative RT-PCR, soft-agar colony formation assay, migration/invasion assays","journal":"The Journal of biological chemistry","confidence":"Low","confidence_rationale":"Tier 3 — single lab Co-IP plus domain mapping plus functional assays, moderate mechanistic follow-up","pmids":["32554467"],"is_preprint":false},{"year":2023,"finding":"UNC119 deletion from even one allele reduces steady-state glutamate release at rod synapses (depolarizes bipolar cell membrane potential, decreases sensitivity, accelerates response decay), without affecting rod outer segment photocurrent or voltage dependence of synaptic Ca current; this effect persists after transducin translocation, implicating an interaction with RIBEYE or other synaptic proteins rather than CaBP4 or calcium channels.","method":"Patch-clamp recordings from retinal slices in UNC119 heterozygous and knockout mice, background light adaptation experiments","journal":"International journal of molecular sciences","confidence":"Medium","confidence_rationale":"Tier 2 — electrophysiology in defined genetic model with functional specificity established","pmids":["37175812"],"is_preprint":false},{"year":2025,"finding":"UNC119 traffics LCK to the immunological synapse in T cells; inhibiting UNC119 reduces LCK localization at the synapse without impairing LCK phosphorylation, thereby reducing TCR signal transduction; UNC119 is also required to sustain proliferation in T-ALL cells.","method":"UNC119 inhibition, live-cell imaging of LCK localization, TCR signaling assays, cytotoxicity assays, T-ALL cell proliferation assays","journal":"Life science alliance","confidence":"Medium","confidence_rationale":"Tier 2 — direct localization experiment with functional signaling readout, pharmacological inhibition","pmids":["39814552"],"is_preprint":false},{"year":2025,"finding":"UNC119 interacts with Gnat2 (cone transducin α-subunit) in cone photoreceptors and is essential for Gnat2 translocation to the outer segment; UNC119 deficiency leads to activation of JAK-STAT and NF-κB inflammatory pathways in the retina; a human CRD-associated UNC119 mutant competitively inhibits UNC119 interaction with both GNAT1 and GNAT2; curcumin treatment targeting these inflammatory pathways suppresses cone degeneration in Unc119-KO mice.","method":"Unc119 knockout mouse, co-immunoprecipitation, RNA-seq, immunofluorescence for Gnat2 localization, curcumin treatment experiment","journal":"The Journal of neuroscience","confidence":"High","confidence_rationale":"Tier 2 — Co-IP plus KO with defined localization phenotype plus transcriptomic pathway analysis plus pharmacological rescue","pmids":["41107067"],"is_preprint":false}],"current_model":"UNC119 is an immunoglobulin-like β-sandwich lipid-binding chaperone that sequesters myristoylated cargo proteins (including transducin α-subunits Gαt1 and Gαt2, NPHP3, and Src family kinases) via a hydrophobic pocket, forming soluble diffusible complexes that enable transport between membrane compartments; cargo release is triggered specifically by ARL3-GTP (and for low-affinity cargo also by ARL2-GTP) through allosteric widening of the hydrophobic pocket, targeting myristoylated proteins to the primary cilium and plasma membrane; UNC119 also functions as an activator of Src-family kinases (Lck, Fyn, Lyn) at immune receptor complexes through SH2/SH3 interactions, an inhibitor of dynamin GTPase activity to regulate endocytosis, a component of photoreceptor ribbon synapses via RIBEYE interaction that facilitates glutamate release, and a scaffold that promotes the KRAS-RASSF6-MDM2-p53 apoptotic axis."},"narrative":{"teleology":[{"year":1995,"claim":"Establishing UNC-119 as a novel neural gene: its identification in C. elegans revealed that a previously unknown protein is required pan-neuronally for locomotion, feeding, and chemosensation, posing the question of its molecular function.","evidence":"Genetic mapping, transgenic rescue, and lacZ reporter in C. elegans","pmids":["8582641"],"confidence":"Medium","gaps":["Molecular function completely unknown","No vertebrate ortholog characterized","Subcellular localization unresolved"]},{"year":1998,"claim":"Localizing the vertebrate ortholog to photoreceptor synapses narrowed the functional question from generic neural role to a specific site of action in neurotransmission.","evidence":"Immunofluorescence and electron microscopic immunolocalization in human retina","pmids":["9538874"],"confidence":"Medium","gaps":["No binding partner identified","Functional consequence of synaptic localization untested"]},{"year":2000,"claim":"Cross-species rescue and disease association established that UNC119 is functionally conserved across metazoans and that its disruption causes cone-rod dystrophy, linking molecular dysfunction to human retinal disease.","evidence":"Transgenic rescue of C. elegans unc-119 with human/Drosophila orthologs; human truncation mutation modeled in transgenic mice causing retinal degeneration with ERG defects","pmids":["10858820","11006213"],"confidence":"High","gaps":["Mechanism of synaptic dysfunction unknown","Direct binding partners at the synapse unidentified","Whether the truncation acts as dominant-negative vs. haploinsufficiency unclear"]},{"year":2001,"claim":"Demonstrating cell-autonomous suppression of axon branching revealed a post-developmental role for UNC-119 in maintaining neuronal morphology, distinct from its synaptic function.","evidence":"Live imaging of growth cone dynamics and temporally controlled rescue in C. elegans motor neurons","pmids":["11641230"],"confidence":"High","gaps":["Molecular pathway downstream of UNC-119 in axon stabilization unknown","Whether this function is conserved in vertebrates untested"]},{"year":2002,"claim":"Discovery of UNC119 as an activator of Src-family kinases via SH2/SH3 interactions opened a second functional axis—signal transduction—beyond photoreceptor biology.","evidence":"Yeast two-hybrid, co-immunoprecipitation, kinase activity assays with Lyn in eosinophils","pmids":["12496276"],"confidence":"Medium","gaps":["Structural basis of SFK activation unknown","Whether UNC119-SFK interaction is direct in vivo vs. mediated by acylation unclear"]},{"year":2003,"claim":"Identification of ARL2 as a binding partner, combined with structural homology to PDEδ, first suggested that UNC119 functions as a lipid-binding protein regulated by ARL-family GTPases.","evidence":"Yeast two-hybrid, co-immunoprecipitation, direct binding analysis","pmids":["12527357"],"confidence":"Medium","gaps":["No structural evidence for lipid binding","Functional consequence of ARL2 interaction unknown","Single-lab finding"]},{"year":2004,"claim":"Essential role in T cell activation was established: UNC119 associates with TCR complex components and is required for Lck/Fyn activation and IL-2 production, demonstrating immune system relevance.","evidence":"Co-IP with CD3/CD4, kinase assays, UNC119-deficient T cells with reconstitution","pmids":["14757743"],"confidence":"High","gaps":["Mechanism of Lck/Fyn activation unresolved—direct kinase activation vs. membrane delivery unclear","In vivo immune phenotype not characterized"]},{"year":2006,"claim":"Pathogenic mechanism of truncated UNC119 was elucidated (enhanced ARL2 sequestration leading to mitochondrial dysfunction and apoptosis), while separately KO mice revealed a second function in photoreceptor inner/outer segments beyond the synapse.","evidence":"Saturation binding, mitochondrial/apoptotic readouts in transgenic mice; independent KO mouse with ERG and EM analysis","pmids":["16565359","17174953"],"confidence":"High","gaps":["How UNC119 functions in outer segments mechanistically undefined","Whether ARL2 sequestration is the sole disease mechanism for the truncation mutant uncertain"]},{"year":2008,"claim":"RIBEYE was identified as a direct synaptic partner, localizing UNC119 to ribbon synapses through its PDEδ-homology domain, providing a molecular basis for its role in glutamate release.","evidence":"Five orthogonal binding assays including mutagenesis of RIBEYE; CaBP4 interaction confirmed separately","pmids":["18664567","18296658"],"confidence":"High","gaps":["How UNC119-RIBEYE interaction modulates vesicle release unknown","Relative contribution of CaBP4 vs. RIBEYE interaction unclear"]},{"year":2009,"claim":"Two additional molecular activities were uncovered—inhibition of dynamin GTPase activity to regulate endocytosis, and inhibition of Abl kinases—expanding UNC119's role to membrane trafficking and pathogen defense.","evidence":"Co-IP, GTPase assays, endocytosis assays (transferrin/albumin uptake); Abl kinase assays plus in vivo Shigella infection model","pmids":["19781630","19381274"],"confidence":"Medium","gaps":["Whether dynamin and Abl interactions occur through the hydrophobic pocket or distinct surfaces unknown","Physiological relevance of endocytosis regulation in vivo unestablished","Single-lab findings for each"]},{"year":2011,"claim":"The core molecular mechanism was solved: crystal structures revealed an immunoglobulin-like β-sandwich with a hydrophobic cavity that buries myristoyl chains, and UNC119 was shown to function as a myristoyl-dependent chaperone for transducin and ciliary G proteins, with ARL3-GTP releasing cargo for ciliary targeting.","evidence":"Crystal structures at 1.95–2.0 Å, ITC, KO mice and C. elegans; parallel identification of myristoylated NPHP3 as cargo released by ARL3-GTP using structure-guided mutagenesis","pmids":["21642972","21712387","22085962"],"confidence":"High","gaps":["Full cargo repertoire unknown","How cargo specificity for ciliary vs. non-ciliary destinations is encoded at residue level unresolved"]},{"year":2012,"claim":"Structural comparison of ARL3-GTP vs. ARL2-GTP complexes with UNC119 explained the ~1000-fold selectivity for ARL3 in cargo release: ARL3's surface-bound amphipathic helix allosterically widens the myristoyl pocket, a mechanism distinct from PDEδ regulation.","evidence":"Crystal structures of ARL3-UNC119 and ARL2-UNC119 complexes plus dissociation kinetics","pmids":["22960633"],"confidence":"High","gaps":["Whether ARL2 contributes to cargo release for low-affinity substrates in cells untested at this point","Structural basis for cargo discrimination not yet defined"]},{"year":2016,"claim":"A structural code for cargo sorting was defined: residues at +2/+3 positions of the myristoylated peptide determine binding affinity, and high-affinity ciliary cargoes are released exclusively by ARL3-GTP while low-affinity cargoes respond to both ARL2 and ARL3, establishing a biophysical basis for spatial sorting.","evidence":"Crystal structure of myristoylated NPHP3 peptide with UNC119a, ITC affinity measurements, cargo mutagenesis with cellular mislocalization assays","pmids":["27481943"],"confidence":"High","gaps":["Whether additional factors besides affinity contribute to sorting in vivo","Complete set of high- vs. low-affinity cargoes not catalogued"]},{"year":2017,"claim":"The spatial cycle for non-ciliary cargo was visualized: UNC119 captures Src-family kinases from endomembranes, diffuses as a soluble complex, and delivers them to the plasma membrane via ARL2/3-dependent release at recycling endosomes, maintaining SFK enrichment at the cell surface.","evidence":"Live-cell imaging, FRAP, siRNA, quantitative fluorescence microscopy","pmids":["28740133"],"confidence":"High","gaps":["Whether recycling endosome localization of ARL2/3 is regulated","Relative contribution of ARL2 vs. ARL3 at recycling endosomes unresolved"]},{"year":2023,"claim":"Electrophysiology in heterozygous and KO mice demonstrated that even partial UNC119 loss reduces steady-state glutamate release without affecting photocurrent or synaptic calcium channels, functionally separating its ribbon synapse role from transducin trafficking.","evidence":"Patch-clamp recordings from retinal slices in UNC119 heterozygous and KO mice","pmids":["37175812"],"confidence":"Medium","gaps":["Molecular mechanism by which UNC119 facilitates vesicle release at the ribbon unresolved","Whether the effect is mediated by RIBEYE interaction or another partner untested"]},{"year":2025,"claim":"UNC119 was shown to traffic LCK to the immunological synapse (distinct from activating its kinase activity) and to be essential for cone transducin (Gnat2) outer-segment localization; UNC119 deficiency triggers retinal inflammation via JAK-STAT and NF-κB pathways.","evidence":"UNC119 inhibition with live-cell LCK imaging and TCR signaling in T cells; Unc119 KO mice with co-IP, RNA-seq, immunofluorescence, and curcumin rescue for cone degeneration","pmids":["39814552","41107067"],"confidence":"High","gaps":["Whether inflammatory pathways are a direct consequence of transducin mislocalization or secondary to photoreceptor stress unknown","Whether UNC119 trafficking of LCK is mechanistically identical to its SFK plasma-membrane cycle unclear"]},{"year":null,"claim":"Key open questions include the complete inventory of myristoylated UNC119 cargo, the structural basis for UNC119's interactions outside its hydrophobic pocket (dynamin, RIBEYE, KRAS-RASSF6 axis), and whether UNC119's synaptic and ciliary functions can be therapeutically uncoupled.","evidence":"","pmids":[],"confidence":"Medium","gaps":["Full myristoylated cargo repertoire uncharacterized","No structural model for UNC119-RIBEYE or UNC119-dynamin interaction","In vivo immune phenotype of UNC119 deficiency not fully described"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0008289","term_label":"lipid binding","supporting_discovery_ids":[15,16,17,18,19]},{"term_id":"GO:0044183","term_label":"protein folding chaperone","supporting_discovery_ids":[15,17,20]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[5,7,10,13,14]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[17,20,26]}],"localization":[{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[15,20]},{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[1,20,26]},{"term_id":"GO:0005929","term_label":"cilium","supporting_discovery_ids":[17,19]},{"term_id":"GO:0005768","term_label":"endosome","supporting_discovery_ids":[20]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[5,7,10,20,26]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[7,26]},{"term_id":"R-HSA-9609507","term_label":"Protein localization","supporting_discovery_ids":[15,17,19,20,27]},{"term_id":"R-HSA-112316","term_label":"Neuronal System","supporting_discovery_ids":[0,4,25]},{"term_id":"R-HSA-9709957","term_label":"Sensory Perception","supporting_discovery_ids":[3,9,15,27]}],"complexes":["UNC119-ARL3-GTP cargo release complex","UNC119-transducin complex","UNC119-RIBEYE synaptic ribbon complex"],"partners":["ARL3","ARL2","GNAT1","GNAT2","NPHP3","RIBEYE","LCK","FYN"],"other_free_text":[]},"mechanistic_narrative":"UNC119 is a myristoyl-binding chaperone with an immunoglobulin-like β-sandwich fold that sequesters acylated cargo proteins in a deep hydrophobic pocket, enabling their soluble transport between membrane compartments and regulated delivery to specific destinations including the primary cilium and plasma membrane [PMID:21642972, PMID:22085962, PMID:27481943]. Cargo release is driven by ARL3-GTP, which allosterically widens the hydrophobic pocket to accelerate dissociation ~1000-fold; high-affinity ciliary cargoes (transducin Gαt1/Gαt2, NPHP3) are released exclusively by ARL3-GTP, while lower-affinity cargoes such as Src-family kinases can also be released by ARL2-GTP, thereby spatially sorting myristoylated proteins to cilia versus the plasma membrane [PMID:22960633, PMID:27481943, PMID:28740133]. UNC119 additionally functions at photoreceptor ribbon synapses—interacting with RIBEYE and facilitating steady-state glutamate release—and in T cells, where it traffics LCK to the immunological synapse and activates Src-family kinases to promote TCR signaling [PMID:18664567, PMID:37175812, PMID:14757743, PMID:39814552]. Heterozygous truncating mutations in UNC119 cause late-onset cone-rod dystrophy, and complete loss leads to progressive photoreceptor degeneration with mislocalization of both rod and cone transducin α-subunits [PMID:11006213, PMID:16565359, PMID:41107067]."},"prefetch_data":{"uniprot":{"accession":"Q13432","full_name":"Protein unc-119 homolog A","aliases":["Retinal protein 4","hRG4"],"length_aa":240,"mass_kda":27.0,"function":"Involved in synaptic functions in photoreceptor cells, the signal transduction in immune cells as a Src family kinase activator, endosome recycling, the uptake of bacteria and endocytosis, protein trafficking in sensory neurons and as lipid-binding chaperone with specificity for a diverse subset of myristoylated proteins. Specifically binds the myristoyl moiety of a subset of N-terminally myristoylated proteins and is required for their localization. Binds myristoylated GNAT1 and is required for G-protein localization and trafficking in sensory neurons. Probably plays a role in trafficking proteins in photoreceptor cells. Plays important roles in mediating Src family kinase signals for the completion of cytokinesis via RAB11A","subcellular_location":"Cytoplasm, cytoskeleton, microtubule organizing center, centrosome; Cytoplasm, cytoskeleton, spindle pole; Cytoplasm, cytoskeleton, spindle","url":"https://www.uniprot.org/uniprotkb/Q13432/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/UNC119","classification":"Not Classified","n_dependent_lines":71,"n_total_lines":1208,"dependency_fraction":0.058774834437086095},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/UNC119","total_profiled":1310},"omim":[{"mim_id":"620513","title":"UNC119 LIPID-BINDING CHAPERONE B; UNC119B","url":"https://www.omim.org/entry/620513"},{"mim_id":"620342","title":"CONE-ROD DYSTROPHY 24; CORD24","url":"https://www.omim.org/entry/620342"},{"mim_id":"619926","title":"KELCH-LIKE FAMILY, MEMBER 18; KLHL18","url":"https://www.omim.org/entry/619926"},{"mim_id":"615518","title":"IMMUNODEFICIENCY 13; IMD13","url":"https://www.omim.org/entry/615518"},{"mim_id":"604695","title":"ADP-RIBOSYLATION FACTOR-LIKE GTPase 3; ARL3","url":"https://www.omim.org/entry/604695"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Tissue enriched","tissue_distribution":"Detected in 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acid-induced cell-cycle dysregulation through the Gsk3β/β-catenin pathway in hepatocellular carcinoma cells.","date":"2016","source":"Anti-cancer drugs","url":"https://pubmed.ncbi.nlm.nih.gov/27669172","citation_count":5,"is_preprint":false},{"pmid":"38872845","id":"PMC_38872845","title":"Streamlined single shot safe harbor transgene integration in C. elegans using unc-119 rescue.","date":"2024","source":"microPublication biology","url":"https://pubmed.ncbi.nlm.nih.gov/38872845","citation_count":5,"is_preprint":false},{"pmid":"30610799","id":"PMC_30610799","title":"UNC119 promoted cell growth and migration by Wnt/β-catenin signal and TGF-β/EMT signal pathway in hepatocellular carcinoma.","date":"2018","source":"Journal of B.U.ON. : official journal of the Balkan Union of Oncology","url":"https://pubmed.ncbi.nlm.nih.gov/30610799","citation_count":5,"is_preprint":false},{"pmid":"15892079","id":"PMC_15892079","title":"Novel Caenorhabditis elegans unc-119 axon outgrowth defects correlate 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neuroscience : the official journal of the Society for Neuroscience","url":"https://pubmed.ncbi.nlm.nih.gov/41107067","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":23348,"output_tokens":6619,"usd":0.084665},"stage2":{"model":"claude-opus-4-6","input_tokens":10370,"output_tokens":4072,"usd":0.230475},"total_usd":0.31514,"stage1_batch_id":"msgbatch_01RPbVc9PDH9zQmYK5Hs6srm","stage2_batch_id":"msgbatch_01JVbVLzeKN2yVrsGp3zC8aM","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1995,\n      \"finding\": \"unc-119 is expressed throughout the C. elegans nervous system and is required for locomotion, feeding behavior, and chemosensation; the UNC-119 protein is predicted to be a novel protein with no similarity to other known proteins at that time.\",\n      \"method\": \"Genetic mapping, transgenic rescue, reporter gene (unc-119/lacZ fusion), phenotypic characterization\",\n      \"journal\": \"Genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — clean loss-of-function with defined neural phenotype and transgenic rescue, foundational paper\",\n      \"pmids\": [\"8582641\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1998,\n      \"finding\": \"HRG4 (UNC119) protein is localized specifically to the synaptic termini of rod and cone photoreceptors in the outer plexiform layer, on presynaptic membranes and cytoplasm, suggesting a function in photoreceptor neurotransmission.\",\n      \"method\": \"Immunofluorescence and electron microscopic immunolocalization, Western blot (retina-specific expression)\",\n      \"journal\": \"Investigative ophthalmology & visual science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — direct subcellular localization by EM and immunofluorescence in retinal tissue\",\n      \"pmids\": [\"9538874\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"The conserved C-terminal domain of human HRG4/UNC119 is functionally required; expression of human or Drosophila UNC119 in C. elegans unc-119 mutants fully rescues the mutant phenotype, establishing functional conservation across metazoans.\",\n      \"method\": \"Transgenic rescue experiments in C. elegans with heterologous UNC119 constructs and domain deletions\",\n      \"journal\": \"Journal of neurogenetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — domain-deletion transgenic rescue defines functional region\",\n      \"pmids\": [\"10858820\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"A heterozygous premature termination mutation in HRG4 (UNC119) causes late-onset cone-rod dystrophy in a patient, and transgenic mice expressing the identical truncation mutation develop age-dependent retinal degeneration with defects consistent with photoreceptor synaptic transmission dysfunction (depressed b-wave, normal c-wave).\",\n      \"method\": \"Transgenic mouse model, ERG, funduscopy, histopathology\",\n      \"journal\": \"Investigative ophthalmology & visual science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — human mutation confirmed in transgenic model with defined functional phenotype\",\n      \"pmids\": [\"11006213\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"UNC-119 acts cell-autonomously in neurons to suppress axon branching; in unc-119 mutants, motor neuron commissures develop supernumerary branches after development is complete, with secondary growth cones sprouting from existing axons, and this defect can be suppressed by post-embryonic UNC-119 expression.\",\n      \"method\": \"Live imaging of growth cone dynamics, genetic rescue with temporal control, loss-of-function analysis\",\n      \"journal\": \"Development (Cambridge, England)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — live imaging + temporal rescue establishes cell-autonomous role in axon stabilization\",\n      \"pmids\": [\"11641230\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"UNC119 interacts with Src family tyrosine kinases (Lyn) via SH2 and SH3 domains and activates their catalytic activity; it also associates with the IL-5Rα receptor; UNC119 overexpression prolongs eosinophil survival by increasing Lyn activity.\",\n      \"method\": \"Yeast two-hybrid, co-immunoprecipitation, kinase activity assays, overexpression in eosinophils\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — yeast two-hybrid plus Co-IP plus kinase activity assay in primary cells\",\n      \"pmids\": [\"12496276\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"HRG4 (UNC119) interacts with ARL2 (ADP-ribosylation factor-like protein 2); the interaction was identified by yeast two-hybrid and confirmed by co-immunoprecipitation and direct binding analysis; residues in HRG4 homologous to those in PDEδ that form the hydrophobic pocket are conserved, suggesting a similar binding mechanism.\",\n      \"method\": \"Yeast two-hybrid, co-immunoprecipitation, direct binding analysis, immunofluorescence co-localization\",\n      \"journal\": \"FEBS letters\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 — Co-IP and direct binding confirmed, but single lab\",\n      \"pmids\": [\"12527357\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"UNC119 associates with CD3 and CD4 in T cells, activates Lck and Fyn kinases, and is essential for T cell activation; UNC119-deficient T cells have dramatically reduced Lck/Fyn activity, decreased IL-2 production, and impaired proliferation; reconstitution with UNC119 reverses these defects.\",\n      \"method\": \"Co-immunoprecipitation, kinase activity assays, UNC119-deficient T cells, reconstitution experiments\",\n      \"journal\": \"The Journal of experimental medicine\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — Co-IP, kinase assays, KO/reconstitution with defined signaling phenotype\",\n      \"pmids\": [\"14757743\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"The truncated HRG4 mutant protein exhibits approximately 3-fold greater affinity for ARL2 compared to wild-type HRG4, leading to sequestration of ARL2, reduced ANT-1 in photoreceptor synaptic mitochondria, mitochondrial dysfunction, cytochrome c release and caspase 3 activation within photoreceptor synapses, and ultimately apoptosis — establishing a novel synaptic degeneration pathway.\",\n      \"method\": \"Saturation binding analysis, Western blot, immunofluorescence, TUNEL, morphometric analysis in transgenic mouse model\",\n      \"journal\": \"Investigative ophthalmology & visual science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — saturation binding plus multiple downstream mechanistic readouts in vivo\",\n      \"pmids\": [\"16565359\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"Knockout of HRG4 (MRG4) in mice causes a slowly progressive retinal degeneration distinct from the transgenic truncation model, with early dysfunction in the distal photoreceptor (inner/outer segments), revealing a second function for UNC119 outside the synapse.\",\n      \"method\": \"Gene targeting/knockout mouse, ERG, Western blot, immunofluorescence, EM, TUNEL\",\n      \"journal\": \"Experimental eye research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — clean KO with defined cellular phenotype and comparison to TG model establishing dual functionality\",\n      \"pmids\": [\"17174953\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"UNC119 activates Fyn kinase and is required for TGF-β/PDGF-induced Fyn phosphorylation; UNC119 overexpression stimulates p38 MAPK (but not JNK), and p38 pathway activity downstream of UNC119 is required for α-SMA induction and myofibroblast differentiation; this mechanism requires Fyn as demonstrated by reconstitution in SYF cells.\",\n      \"method\": \"Co-precipitation, co-localization, kinase activity assays, siRNA knockdown, overexpression in SYF cells and human lung fibroblasts, p38 inhibitor experiments\",\n      \"journal\": \"Journal of immunology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — epistasis in SYF reconstitution plus multiple biochemical readouts\",\n      \"pmids\": [\"17579091\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Munc119/UNC119 is recruited to photoreceptor synaptic ribbons through direct interaction with the RIBEYE protein; the PrBP/delta homology domain of Munc119 is essential for binding to the NADH-binding region of the RIBEYE(B) domain; the RIBEYE-Munc119 interaction is independent of NADH binding.\",\n      \"method\": \"Five independent approaches: yeast two-hybrid, co-immunoprecipitation, direct binding assays, affinity chromatography, point mutant analysis (RE(B)E844Q)\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — five orthogonal methods including mutagenesis in a single study\",\n      \"pmids\": [\"18664567\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"CaBP4 directly interacts with UNC119 at the photoreceptor synapse; reduction in UNC119 levels is observed in photoreceptor terminals of CaBP4-knockout mice, suggesting a functional relationship for neurotransmitter release.\",\n      \"method\": \"Affinity chromatography, yeast two-hybrid, co-immunoprecipitation, gel overlay assay, immunohistochemistry in CaBP4-KO mice\",\n      \"journal\": \"Investigative ophthalmology & visual science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — multiple binding assays plus in vivo KO evidence\",\n      \"pmids\": [\"18296658\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"UNC119 interacts with dynamin and inhibits its GTPase activity; binding of UNC119 to dynamin decreases its association with amphiphysin; UNC119 overexpression inhibits clathrin- and caveolae-based endocytosis, while depletion increases endocytosis.\",\n      \"method\": \"Co-immunoprecipitation, GTPase activity assay, endocytosis assays (transferrin, FM4-64, albumin uptake), overexpression/knockdown\",\n      \"journal\": \"Cellular signalling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — Co-IP plus in vitro GTPase assay plus functional endocytosis readouts\",\n      \"pmids\": [\"19781630\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"UNC119 interacts with Abl family kinases and inhibits their kinase activity, thereby inhibiting Crk phosphorylation and reducing Shigella cell invasion; UNC119 co-localizes with Crk and Shigella in infected cells.\",\n      \"method\": \"Co-immunoprecipitation, kinase activity assays, siRNA knockdown, in vivo mouse model of shigellosis\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — biochemical inhibition assay plus in vivo KD with functional phenotype\",\n      \"pmids\": [\"19381274\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"UNC119 recognizes and tightly binds the acylated (myristoylated/lauroylated) N-terminus of the rod transducin α subunit (Gαt1) and C. elegans G proteins ODR-3 and GPA-13; the crystal structure of human UNC119 at 1.95 Å reveals an immunoglobulin-like β-sandwich fold with a hydrophobic cavity that buries the lipid chain; co-crystal structure with acylated Tα peptide at 2.0 Å shows the lipid buried deeply in the cavity; UNC119 binding to Tα-GTP inhibits GTPase activity, stabilizing a diffusible UNC119-Tα-GTP complex; UNC119 deletion causes G protein mislocalization in mouse and C. elegans.\",\n      \"method\": \"Crystal structure (1.95 Å and 2.0 Å co-crystal), isothermal titration calorimetry, pulldowns, UNC119 knockout mouse and C. elegans\",\n      \"journal\": \"Nature neuroscience\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — crystal structures plus ITC plus in vivo KO, replicated findings\",\n      \"pmids\": [\"21642972\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Human UNC119 (HRG4) interaction with transducin (Gαt1) requires N-acylation but not the GTP-bound form; UNC119 binds myristoylated Gαt1 with much higher affinity than prenylated substrates; UNC119 can interact with Gαt1-GDP and heterotrimeric transducin, displacing Gβ1γ1 and facilitating solubilization of transducin from rod outer segment membranes; UNC119 inhibits rhodopsin-dependent Gt activation and inhibits Go activation by D2 dopamine receptor in cultured cells.\",\n      \"method\": \"Pulldown assays, GTPase activity assays, membrane solubilization assay, cell-based GPCR activation assay\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal biochemical assays establishing binding specificity and functional consequences\",\n      \"pmids\": [\"21712387\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"UNC119 (specifically UNC119b) functions as a chaperone for myristoylated NPHP3, binding NPHP3 via its N-terminal 200 residues in a myristoylation-dependent manner; ARL3-GTP releases myristoylated cargo from UNC119b; ARL3, UNC119b, and the ARL3 GAP RP2 are all required for NPHP3 ciliary targeting; UNC119b myristoyl-binding activity is required for this targeting; conserved phenylalanines in a hydrophobic β-sandwich are essential for myristate binding.\",\n      \"method\": \"Proteomic approach, co-immunoprecipitation, directed mutagenesis of predicted structural residues, UNC119b knockdown in IMCD3 cells, C. elegans genetics\",\n      \"journal\": \"Genes & development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — structure-guided mutagenesis plus proteomic identification plus functional knockdown, replicated by multiple labs\",\n      \"pmids\": [\"22085962\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Crystal structures of Arl3 and Arl2 in complex with UNC119a show both bind with similar affinities, but only Arl3-GTP allosterically displaces myristoylated cargo by accelerating release by ~1000-fold; this is due to the N-terminal amphipathic helix of Arl3·GppNHp remaining surface-bound and inducing widening of the myristoyl binding pocket, opposite to the PDEδ mechanism.\",\n      \"method\": \"Crystal structures of Arl3/Arl2 complexes with UNC119a, dissociation kinetics, affinity measurements\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — crystal structures plus kinetic measurements revealing molecular basis of Arl3 specificity\",\n      \"pmids\": [\"22960633\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"Myristoylated ciliary cargo peptides (GNAT1, NPHP3, Cystin1) bind UNC119a and UNC119b with subnanomolar affinities, while non-ciliary Src peptide has low affinity; high-affinity cargo is exclusively released by Arl3·GppNHp but not Arl2; low-affinity cargo is released by both; crystal structure of myristoylated NPHP3 peptide with UNC119a identifies residues at +2/+3 positions as determinants of binding affinity; swapping these residues reverses affinities and causes mislocalization.\",\n      \"method\": \"X-ray crystal structure, ITC/affinity measurements, mutagenesis of cargo peptides, cellular localization assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — crystal structure plus mutagenesis plus affinity measurements plus cellular validation\",\n      \"pmids\": [\"27481943\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"UNC119 sequesters myristoylated Src family kinases (SFKs) from the cytoplasm, forming a soluble complex that enables diffusion to the recycling endosome, where localized Arl2/3 activity releases SFKs; this spatial cycle maintains SFK enrichment at the plasma membrane; UNC119 knockdown disrupts SFK plasma membrane localization and signaling activity.\",\n      \"method\": \"Live-cell imaging, FRAP, siRNA knockdown, quantitative fluorescence microscopy, biochemical fractionation\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — direct live-cell localization experiments plus KD with defined signaling phenotype, multiple orthogonal approaches\",\n      \"pmids\": [\"28740133\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Squarunkin A, a small-molecule inhibitor, selectively inhibits UNC119A binding to a myristoylated Src N-terminal peptide with IC50 ~10 nM, binds UNC119 proteins in cell lysate, and interferes with Src kinase activation, demonstrating the druggability of the UNC119-cargo interaction.\",\n      \"method\": \"Biochemical binding assay (IC50 determination), cell lysate binding, Src kinase activity assay\",\n      \"journal\": \"Angewandte Chemie (International ed. in English)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — in vitro binding plus cell-based kinase assay with small-molecule tool\",\n      \"pmids\": [\"28471079\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"UNC119 (UNC119A) interacts with RASSF6 tumor suppressor, promotes RASSF6-MDM2 interaction, and stabilizes p53, inducing apoptosis; UNC119 depletion impairs DNA repair after damage and results in polyploid cell generation.\",\n      \"method\": \"Immunoprecipitation, RNAi knockdown, cell biology assays (apoptosis, DNA damage repair, ploidy)\",\n      \"journal\": \"Cancer science\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 — single Co-IP plus KD phenotype, single lab\",\n      \"pmids\": [\"29931788\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"UNC119a plays a role in cytokinesis; lipidated stapled peptides derived from the Gnat1 UNC119-binding region bind UNC119a and induce accumulation of cytokinetic and binucleated cells upon cell treatment.\",\n      \"method\": \"Hydrocarbon peptide-stapling, cell-based assays (cytokinesis phenotype), binding assays\",\n      \"journal\": \"Chembiochem\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 — pharmacological perturbation with phenotypic readout, no direct molecular mechanism established\",\n      \"pmids\": [\"31680402\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"UNC119A interacts with the active form of KRAS (requiring C-terminal KRAS modification but not the hydrophobic pocket of UNC119A), promotes KRAS-RASSF6 interaction, enhances RASSF6-MDM2 binding, and induces apoptosis; UNC119A silencing promotes soft-agar colony formation, migration, and invasiveness in KRAS-mutated cancer cells.\",\n      \"method\": \"Immunoprecipitation, RNAi gene silencing, quantitative RT-PCR, soft-agar colony formation assay, migration/invasion assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 — single lab Co-IP plus domain mapping plus functional assays, moderate mechanistic follow-up\",\n      \"pmids\": [\"32554467\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"UNC119 deletion from even one allele reduces steady-state glutamate release at rod synapses (depolarizes bipolar cell membrane potential, decreases sensitivity, accelerates response decay), without affecting rod outer segment photocurrent or voltage dependence of synaptic Ca current; this effect persists after transducin translocation, implicating an interaction with RIBEYE or other synaptic proteins rather than CaBP4 or calcium channels.\",\n      \"method\": \"Patch-clamp recordings from retinal slices in UNC119 heterozygous and knockout mice, background light adaptation experiments\",\n      \"journal\": \"International journal of molecular sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — electrophysiology in defined genetic model with functional specificity established\",\n      \"pmids\": [\"37175812\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"UNC119 traffics LCK to the immunological synapse in T cells; inhibiting UNC119 reduces LCK localization at the synapse without impairing LCK phosphorylation, thereby reducing TCR signal transduction; UNC119 is also required to sustain proliferation in T-ALL cells.\",\n      \"method\": \"UNC119 inhibition, live-cell imaging of LCK localization, TCR signaling assays, cytotoxicity assays, T-ALL cell proliferation assays\",\n      \"journal\": \"Life science alliance\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — direct localization experiment with functional signaling readout, pharmacological inhibition\",\n      \"pmids\": [\"39814552\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"UNC119 interacts with Gnat2 (cone transducin α-subunit) in cone photoreceptors and is essential for Gnat2 translocation to the outer segment; UNC119 deficiency leads to activation of JAK-STAT and NF-κB inflammatory pathways in the retina; a human CRD-associated UNC119 mutant competitively inhibits UNC119 interaction with both GNAT1 and GNAT2; curcumin treatment targeting these inflammatory pathways suppresses cone degeneration in Unc119-KO mice.\",\n      \"method\": \"Unc119 knockout mouse, co-immunoprecipitation, RNA-seq, immunofluorescence for Gnat2 localization, curcumin treatment experiment\",\n      \"journal\": \"The Journal of neuroscience\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — Co-IP plus KO with defined localization phenotype plus transcriptomic pathway analysis plus pharmacological rescue\",\n      \"pmids\": [\"41107067\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"UNC119 is an immunoglobulin-like β-sandwich lipid-binding chaperone that sequesters myristoylated cargo proteins (including transducin α-subunits Gαt1 and Gαt2, NPHP3, and Src family kinases) via a hydrophobic pocket, forming soluble diffusible complexes that enable transport between membrane compartments; cargo release is triggered specifically by ARL3-GTP (and for low-affinity cargo also by ARL2-GTP) through allosteric widening of the hydrophobic pocket, targeting myristoylated proteins to the primary cilium and plasma membrane; UNC119 also functions as an activator of Src-family kinases (Lck, Fyn, Lyn) at immune receptor complexes through SH2/SH3 interactions, an inhibitor of dynamin GTPase activity to regulate endocytosis, a component of photoreceptor ribbon synapses via RIBEYE interaction that facilitates glutamate release, and a scaffold that promotes the KRAS-RASSF6-MDM2-p53 apoptotic axis.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"UNC119 is a myristoyl-binding chaperone with an immunoglobulin-like β-sandwich fold that sequesters acylated cargo proteins in a deep hydrophobic pocket, enabling their soluble transport between membrane compartments and regulated delivery to specific destinations including the primary cilium and plasma membrane [PMID:21642972, PMID:22085962, PMID:27481943]. Cargo release is driven by ARL3-GTP, which allosterically widens the hydrophobic pocket to accelerate dissociation ~1000-fold; high-affinity ciliary cargoes (transducin Gαt1/Gαt2, NPHP3) are released exclusively by ARL3-GTP, while lower-affinity cargoes such as Src-family kinases can also be released by ARL2-GTP, thereby spatially sorting myristoylated proteins to cilia versus the plasma membrane [PMID:22960633, PMID:27481943, PMID:28740133]. UNC119 additionally functions at photoreceptor ribbon synapses—interacting with RIBEYE and facilitating steady-state glutamate release—and in T cells, where it traffics LCK to the immunological synapse and activates Src-family kinases to promote TCR signaling [PMID:18664567, PMID:37175812, PMID:14757743, PMID:39814552]. Heterozygous truncating mutations in UNC119 cause late-onset cone-rod dystrophy, and complete loss leads to progressive photoreceptor degeneration with mislocalization of both rod and cone transducin α-subunits [PMID:11006213, PMID:16565359, PMID:41107067].\",\n  \"teleology\": [\n    {\n      \"year\": 1995,\n      \"claim\": \"Establishing UNC-119 as a novel neural gene: its identification in C. elegans revealed that a previously unknown protein is required pan-neuronally for locomotion, feeding, and chemosensation, posing the question of its molecular function.\",\n      \"evidence\": \"Genetic mapping, transgenic rescue, and lacZ reporter in C. elegans\",\n      \"pmids\": [\"8582641\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular function completely unknown\", \"No vertebrate ortholog characterized\", \"Subcellular localization unresolved\"]\n    },\n    {\n      \"year\": 1998,\n      \"claim\": \"Localizing the vertebrate ortholog to photoreceptor synapses narrowed the functional question from generic neural role to a specific site of action in neurotransmission.\",\n      \"evidence\": \"Immunofluorescence and electron microscopic immunolocalization in human retina\",\n      \"pmids\": [\"9538874\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No binding partner identified\", \"Functional consequence of synaptic localization untested\"]\n    },\n    {\n      \"year\": 2000,\n      \"claim\": \"Cross-species rescue and disease association established that UNC119 is functionally conserved across metazoans and that its disruption causes cone-rod dystrophy, linking molecular dysfunction to human retinal disease.\",\n      \"evidence\": \"Transgenic rescue of C. elegans unc-119 with human/Drosophila orthologs; human truncation mutation modeled in transgenic mice causing retinal degeneration with ERG defects\",\n      \"pmids\": [\"10858820\", \"11006213\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of synaptic dysfunction unknown\", \"Direct binding partners at the synapse unidentified\", \"Whether the truncation acts as dominant-negative vs. haploinsufficiency unclear\"]\n    },\n    {\n      \"year\": 2001,\n      \"claim\": \"Demonstrating cell-autonomous suppression of axon branching revealed a post-developmental role for UNC-119 in maintaining neuronal morphology, distinct from its synaptic function.\",\n      \"evidence\": \"Live imaging of growth cone dynamics and temporally controlled rescue in C. elegans motor neurons\",\n      \"pmids\": [\"11641230\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular pathway downstream of UNC-119 in axon stabilization unknown\", \"Whether this function is conserved in vertebrates untested\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Discovery of UNC119 as an activator of Src-family kinases via SH2/SH3 interactions opened a second functional axis—signal transduction—beyond photoreceptor biology.\",\n      \"evidence\": \"Yeast two-hybrid, co-immunoprecipitation, kinase activity assays with Lyn in eosinophils\",\n      \"pmids\": [\"12496276\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Structural basis of SFK activation unknown\", \"Whether UNC119-SFK interaction is direct in vivo vs. mediated by acylation unclear\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Identification of ARL2 as a binding partner, combined with structural homology to PDEδ, first suggested that UNC119 functions as a lipid-binding protein regulated by ARL-family GTPases.\",\n      \"evidence\": \"Yeast two-hybrid, co-immunoprecipitation, direct binding analysis\",\n      \"pmids\": [\"12527357\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural evidence for lipid binding\", \"Functional consequence of ARL2 interaction unknown\", \"Single-lab finding\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Essential role in T cell activation was established: UNC119 associates with TCR complex components and is required for Lck/Fyn activation and IL-2 production, demonstrating immune system relevance.\",\n      \"evidence\": \"Co-IP with CD3/CD4, kinase assays, UNC119-deficient T cells with reconstitution\",\n      \"pmids\": [\"14757743\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of Lck/Fyn activation unresolved—direct kinase activation vs. membrane delivery unclear\", \"In vivo immune phenotype not characterized\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Pathogenic mechanism of truncated UNC119 was elucidated (enhanced ARL2 sequestration leading to mitochondrial dysfunction and apoptosis), while separately KO mice revealed a second function in photoreceptor inner/outer segments beyond the synapse.\",\n      \"evidence\": \"Saturation binding, mitochondrial/apoptotic readouts in transgenic mice; independent KO mouse with ERG and EM analysis\",\n      \"pmids\": [\"16565359\", \"17174953\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How UNC119 functions in outer segments mechanistically undefined\", \"Whether ARL2 sequestration is the sole disease mechanism for the truncation mutant uncertain\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"RIBEYE was identified as a direct synaptic partner, localizing UNC119 to ribbon synapses through its PDEδ-homology domain, providing a molecular basis for its role in glutamate release.\",\n      \"evidence\": \"Five orthogonal binding assays including mutagenesis of RIBEYE; CaBP4 interaction confirmed separately\",\n      \"pmids\": [\"18664567\", \"18296658\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How UNC119-RIBEYE interaction modulates vesicle release unknown\", \"Relative contribution of CaBP4 vs. RIBEYE interaction unclear\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Two additional molecular activities were uncovered—inhibition of dynamin GTPase activity to regulate endocytosis, and inhibition of Abl kinases—expanding UNC119's role to membrane trafficking and pathogen defense.\",\n      \"evidence\": \"Co-IP, GTPase assays, endocytosis assays (transferrin/albumin uptake); Abl kinase assays plus in vivo Shigella infection model\",\n      \"pmids\": [\"19781630\", \"19381274\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether dynamin and Abl interactions occur through the hydrophobic pocket or distinct surfaces unknown\", \"Physiological relevance of endocytosis regulation in vivo unestablished\", \"Single-lab findings for each\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"The core molecular mechanism was solved: crystal structures revealed an immunoglobulin-like β-sandwich with a hydrophobic cavity that buries myristoyl chains, and UNC119 was shown to function as a myristoyl-dependent chaperone for transducin and ciliary G proteins, with ARL3-GTP releasing cargo for ciliary targeting.\",\n      \"evidence\": \"Crystal structures at 1.95–2.0 Å, ITC, KO mice and C. elegans; parallel identification of myristoylated NPHP3 as cargo released by ARL3-GTP using structure-guided mutagenesis\",\n      \"pmids\": [\"21642972\", \"21712387\", \"22085962\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Full cargo repertoire unknown\", \"How cargo specificity for ciliary vs. non-ciliary destinations is encoded at residue level unresolved\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Structural comparison of ARL3-GTP vs. ARL2-GTP complexes with UNC119 explained the ~1000-fold selectivity for ARL3 in cargo release: ARL3's surface-bound amphipathic helix allosterically widens the myristoyl pocket, a mechanism distinct from PDEδ regulation.\",\n      \"evidence\": \"Crystal structures of ARL3-UNC119 and ARL2-UNC119 complexes plus dissociation kinetics\",\n      \"pmids\": [\"22960633\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether ARL2 contributes to cargo release for low-affinity substrates in cells untested at this point\", \"Structural basis for cargo discrimination not yet defined\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"A structural code for cargo sorting was defined: residues at +2/+3 positions of the myristoylated peptide determine binding affinity, and high-affinity ciliary cargoes are released exclusively by ARL3-GTP while low-affinity cargoes respond to both ARL2 and ARL3, establishing a biophysical basis for spatial sorting.\",\n      \"evidence\": \"Crystal structure of myristoylated NPHP3 peptide with UNC119a, ITC affinity measurements, cargo mutagenesis with cellular mislocalization assays\",\n      \"pmids\": [\"27481943\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether additional factors besides affinity contribute to sorting in vivo\", \"Complete set of high- vs. low-affinity cargoes not catalogued\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"The spatial cycle for non-ciliary cargo was visualized: UNC119 captures Src-family kinases from endomembranes, diffuses as a soluble complex, and delivers them to the plasma membrane via ARL2/3-dependent release at recycling endosomes, maintaining SFK enrichment at the cell surface.\",\n      \"evidence\": \"Live-cell imaging, FRAP, siRNA, quantitative fluorescence microscopy\",\n      \"pmids\": [\"28740133\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether recycling endosome localization of ARL2/3 is regulated\", \"Relative contribution of ARL2 vs. ARL3 at recycling endosomes unresolved\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Electrophysiology in heterozygous and KO mice demonstrated that even partial UNC119 loss reduces steady-state glutamate release without affecting photocurrent or synaptic calcium channels, functionally separating its ribbon synapse role from transducin trafficking.\",\n      \"evidence\": \"Patch-clamp recordings from retinal slices in UNC119 heterozygous and KO mice\",\n      \"pmids\": [\"37175812\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular mechanism by which UNC119 facilitates vesicle release at the ribbon unresolved\", \"Whether the effect is mediated by RIBEYE interaction or another partner untested\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"UNC119 was shown to traffic LCK to the immunological synapse (distinct from activating its kinase activity) and to be essential for cone transducin (Gnat2) outer-segment localization; UNC119 deficiency triggers retinal inflammation via JAK-STAT and NF-κB pathways.\",\n      \"evidence\": \"UNC119 inhibition with live-cell LCK imaging and TCR signaling in T cells; Unc119 KO mice with co-IP, RNA-seq, immunofluorescence, and curcumin rescue for cone degeneration\",\n      \"pmids\": [\"39814552\", \"41107067\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether inflammatory pathways are a direct consequence of transducin mislocalization or secondary to photoreceptor stress unknown\", \"Whether UNC119 trafficking of LCK is mechanistically identical to its SFK plasma-membrane cycle unclear\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"Key open questions include the complete inventory of myristoylated UNC119 cargo, the structural basis for UNC119's interactions outside its hydrophobic pocket (dynamin, RIBEYE, KRAS-RASSF6 axis), and whether UNC119's synaptic and ciliary functions can be therapeutically uncoupled.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Full myristoylated cargo repertoire uncharacterized\", \"No structural model for UNC119-RIBEYE or UNC119-dynamin interaction\", \"In vivo immune phenotype of UNC119 deficiency not fully described\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0008289\", \"supporting_discovery_ids\": [15, 16, 17, 18, 19]},\n      {\"term_id\": \"GO:0044183\", \"supporting_discovery_ids\": [15, 17, 20]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [5, 7, 10, 13, 14]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [17, 20, 26]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [15, 20]},\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [1, 20, 26]},\n      {\"term_id\": \"GO:0005929\", \"supporting_discovery_ids\": [17, 19]},\n      {\"term_id\": \"GO:0005768\", \"supporting_discovery_ids\": [20]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [5, 7, 10, 20, 26]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [7, 26]},\n      {\"term_id\": \"R-HSA-9609507\", \"supporting_discovery_ids\": [15, 17, 19, 20, 27]},\n      {\"term_id\": \"R-HSA-112316\", \"supporting_discovery_ids\": [0, 4, 25]},\n      {\"term_id\": \"R-HSA-9709957\", \"supporting_discovery_ids\": [3, 9, 15, 27]}\n    ],\n    \"complexes\": [\n      \"UNC119-ARL3-GTP cargo release complex\",\n      \"UNC119-transducin complex\",\n      \"UNC119-RIBEYE synaptic ribbon complex\"\n    ],\n    \"partners\": [\n      \"ARL3\",\n      \"ARL2\",\n      \"GNAT1\",\n      \"GNAT2\",\n      \"NPHP3\",\n      \"RIBEYE\",\n      \"LCK\",\n      \"FYN\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}