{"gene":"RASGRP1","run_date":"2026-06-10T06:43:36","timeline":{"discoveries":[{"year":1998,"finding":"RasGRP1 is a guanine nucleotide exchange factor (GEF) for Ras that contains a DAG-binding C1 domain and calcium-binding EF-hand motifs. DAG analog treatment caused sustained Ras-ERK activation and membrane partitioning of RasGRP1; deletion of the DAG-binding domain abolished both membrane recruitment and sustained signaling, establishing that DAG-driven membrane translocation is the primary activation mechanism.","method":"Cell transformation assays in NIH 3T3 fibroblasts, subcellular fractionation, domain deletion mutagenesis, Ras-GTP assays","journal":"Science","confidence":"High","confidence_rationale":"Tier 1 / Strong — original characterization with in vitro GEF assay, domain deletion mutagenesis, and multiple functional readouts; replicated independently in same year","pmids":["9582122"],"is_preprint":false},{"year":1998,"finding":"The C1 domain of RasGRP1 is required for transforming activity; deletion of the C1 domain or an adjacent basic-amino-acid cluster abolished transformation and MAP kinase activation. Replacement of the C1 domain with a membrane-targeting prenylation signal or a PKC C1 domain restored activity, confirming that membrane recruitment via the C1 domain is the mechanistic basis of RasGRP1 activation. Phorbol ester stimulates C1-domain-dependent translocation of RasGRP1 to cell membranes.","method":"NIH 3T3 transformation assay, C1-domain deletion and substitution mutagenesis, MAP kinase activation assay, confocal microscopy of GFP-tagged protein","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 1 / Strong — domain mutagenesis with functional rescue, multiple orthogonal assays, independent replication of core findings","pmids":["9819387"],"is_preprint":false},{"year":2000,"finding":"RasGRP1 is required for TCR-induced Ras activation in T cells. A PLC-γ1 inhibitor reduced TCR-stimulated Ras activation; anti-RasGRP1 antibodies inhibited Ras-guanyl nucleotide exchange activity in TCR-stimulated Jurkat cell membranes. Overexpression of RasGRP1 enhanced TCR-Ras-ERK signaling and IL-2 secretion in response to DAG analogues plus calcium ionophore, directly linking PLC-γ1/DAG to Ras through RasGRP1.","method":"Ras-GTP pull-down assay, antibody inhibition of GEF activity in membrane fractions, RasGRP1 overexpression in Jurkat T cells, ERK activation assay, IL-2 ELISA","journal":"Blood","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal biochemical methods (antibody inhibition, overexpression, GTP-loading assay) in T cells; replicated by knockout mouse study","pmids":["10807788"],"is_preprint":false},{"year":2000,"finding":"RasGRP1 (RasGRP) knockout mice show normal numbers of immature thymocytes but a marked deficiency of mature single-positive (CD4+ and CD8+) thymocytes. Mutant thymocytes completely lack Ras signaling and proliferative responses to DAG analogs or TCR stimulation, establishing RasGRP1 as an essential and non-redundant link between TCR/DAG signaling and Ras activation in thymic development.","method":"Targeted gene knockout in mice, thymocyte FACS phenotyping, Ras activation assay, thymocyte proliferation assay","journal":"Nature immunology","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean knockout with defined cellular and biochemical phenotype, replicated across multiple labs","pmids":["11017103"],"is_preprint":false},{"year":2000,"finding":"The C1 domain of RasGRP1 binds phorbol esters with high affinity (Kd ~0.58 nM for [3H]PDBu), comparable to PKC. Lipid cofactor requirements differ from PKC; calcium does not affect phorbol ester binding to the C1-EF domain, establishing the C1 domain as the primary high-affinity DAG/phorbol ester receptor on RasGRP1.","method":"Radioligand binding assay ([3H]PDBu), competition binding with DAG analogs and PKC inhibitors, phospholipid cofactor requirement analysis","journal":"Molecular pharmacology","confidence":"High","confidence_rationale":"Tier 1 / Strong — quantitative in vitro binding assay with multiple ligands and controls; well-replicated biochemical finding","pmids":["10779365"],"is_preprint":false},{"year":2002,"finding":"Expression of a catalytically inactive diacylglycerol kinase alpha (DGKα) in T cells leads to sustained membrane translocation of RasGRP1 and sustained MAPK activation following TCR or muscarinic receptor stimulation, demonstrating that DGKα-mediated DAG clearance controls the duration of RasGRP1 activation and downstream Ras/MAPK signaling.","method":"Expression of kinase-dead DGKα in T cell lines, time-course imaging of RasGRP1 translocation, MAPK activation assay, DAG measurement","journal":"FASEB journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — dominant-negative approach with functional readout and mechanistic DAG measurement, single lab","pmids":["11919165"],"is_preprint":false},{"year":2003,"finding":"In response to Src-dependent activation of PLCγ1, RasGRP1 translocates to the Golgi apparatus where it activates Ras. Calcium positively regulates Golgi Ras through RasGRP1, while the same messenger negatively regulates plasma membrane Ras via the GAP CAPRI, demonstrating compartmentalized Ras signaling through distinct regulatory mechanisms.","method":"Live-cell imaging of GFP-tagged RasGRP1 and Ras biosensors, dominant-negative and constitutively active construct expression, Ras activation assays in Jurkat T cells","journal":"Nature","confidence":"High","confidence_rationale":"Tier 2 / Strong — live imaging combined with biochemical Ras activation assays and genetic manipulations; published in Nature with independent validation of Golgi Ras signaling","pmids":["12845332"],"is_preprint":false},{"year":2003,"finding":"RasGRP family members are the only Ras activators that localize to and activate Ras at the Golgi. Ras activation at the plasma membrane and ER can be achieved by most GEFs, but GTP loading of Ras at the Golgi is specific to RasGRP proteins, establishing a basis for compartmentalized Ras signaling.","method":"Subcellular fractionation, confocal microscopy of GFP-tagged GEFs, Ras activation assays in different membrane compartments","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple GEFs compared systematically with colocalization and functional Ras activation assays; replicated by Bivona et al.","pmids":["12782630"],"is_preprint":false},{"year":2004,"finding":"The C1 domains of RasGRP1 and PKCθ show distinct subcellular localization in living T lymphocytes despite high structural similarity, with RasGRP1 C1 domain preferentially accumulating at internal membranes (Golgi) following TCR triggering, while PKCθ C1 domain targets the plasma membrane. Overexpression of individual C1 domains can attenuate DAG-dependent signals from respective membranes, establishing these domains as functional DAG discriminators.","method":"Live-cell imaging with fluorescent C1 domain fusion proteins, pharmacological stimulation and TCR triggering, Ras activation reporter assays in Jurkat T cells","journal":"Molecular biology of the cell","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — live imaging with functional consequences, single lab","pmids":["15064353"],"is_preprint":false},{"year":2005,"finding":"RasGRP1 is required for optimal antigen receptor-triggered Ras-ERK activation in T cells, and relies on its DAG-binding domain for selective Erk kinase activation. Phosphorylation of threonine 184 (Thr184) in RasGRP1 correlates with ERK activation and requires novel PKC kinase activities. PKCθ activation is in turn dependent on RasGRP1, establishing a DAG-PKC-RasGRP1-Ras-ERK pathway with positive feedback.","method":"RasGRP1-deficient Jurkat T cell clones, RNAi knockdown, phospho-specific antibodies, domain deletion constructs, PKC pharmacological inhibitors","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple genetic and pharmacological approaches in T cells, site-specific phosphorylation identified, replicated in different systems","pmids":["15899849"],"is_preprint":false},{"year":2007,"finding":"RasGRP1 orchestrates Ras signaling in two ways: (i) by directly activating Ras and (ii) by generating RasGTP that primes the allosteric pocket of SOS, enhancing SOS activity and creating a positive RasGTP-SOS feedback loop. Without RasGRP1, this loop cannot be initiated because SOS requires its own product (RasGTP) for allosteric activation, explaining RasGRP1 dominance in lymphocytes.","method":"Jurkat and DT40 B cell genetic knockouts and reconstitution, allosteric SOS mutants, RasV12C40 expression to substitute RasGRP function, Ras-GTP quantification","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — allosteric mechanism validated with structure-guided mutants, multiple cell lines, and genetic complementation","pmids":["17283063"],"is_preprint":false},{"year":2007,"finding":"RasGRP1 is required for membrane translocation and activation; the tail domain (C-terminal ~200 residues) is essential for membrane trafficking of RasGRP1 following TCR stimulation, and its deletion abolishes ERK activation despite intact C1 and EF domains.","method":"Knock-in mice expressing tail-deleted RasGRP1, TCR stimulation assays, subcellular fractionation, ERK phosphorylation assay, FACS analysis","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — knock-in mouse model with direct localization and signaling readouts, single lab","pmids":["22719950"],"is_preprint":false},{"year":2007,"finding":"The adaptor protein SKAP-55 binds RasGRP1 via its C-terminus in a manner enhanced by SKAP-55 tyrosine phosphorylation. This interaction negatively regulates the Ras-ERK pathway: SKAP-55 deficiency leads to increased RasGRP1 localization at the trans-Golgi network and hyper-activation of ERK following TCR stimulation.","method":"Co-immunoprecipitation, RNAi knockdown, SKAP-55 knockout T cells, confocal microscopy of RasGRP1 localization, ERK phosphorylation assay","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — co-IP binding demonstrated, knockout cells show RasGRP1 mis-localization and functional ERK phenotype, single lab","pmids":["18320039"],"is_preprint":false},{"year":2007,"finding":"BCR-induced plasma membrane targeting of RasGRP1 requires cooperativity between three domains: the C1 domain (binds DAG generated by PLCγ2), the Plasma membrane Targeter (PT) domain (sufficient and essential for plasma membrane targeting), and the Suppressor of PT (SuPT) domain (attenuates constitutive PM localization). In fibroblasts, the PT domain is inactive, so the C1 domain directs RasGRP1 to internal membranes.","method":"Domain deletion and mutational analysis, live fluorescence imaging in B cell lines and fibroblasts, BCR ligation experiments","journal":"Molecular biology of the cell","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — systematic domain dissection with multiple cell types and imaging, single lab","pmids":["17567957"],"is_preprint":false},{"year":2009,"finding":"One EF-hand (EF1) of RasGRP1 is required for receptor-induced translocation to the plasma membrane in B cells by counteracting the SuPT domain, independently of antigen receptor-induced calcium flux. Alternative splicing of EF1 modulates RasGRP1 plasma membrane targeting. The GEF domain Ras-binding site is required for both PT- and C1-mediated membrane localizations, suggesting positive feedback from Ras engagement.","method":"EF-hand mutagenesis, alternative splice isoform expression, calcium chelator experiments, live-cell fluorescence imaging in B cell lines","journal":"Biochimica et biophysica acta","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — mutagenesis combined with live imaging and calcium independence experiments, single lab","pmids":["19168098"],"is_preprint":false},{"year":2011,"finding":"Phosphoinositide 3-kinase (PI3K) signaling controls plasma membrane targeting of RasGRP1. A basic/hydrophobic cluster within the PT domain of RasGRP1 binds directly to phosphoinositide-containing lipid vesicles via electrostatic interactions, and BCR ligation-induced PI3K activity generates plasma membrane phosphoinositides that recruit RasGRP1.","method":"Lipid vesicle binding assays, PI3K inhibitors, mutagenesis of basic/hydrophobic cluster, BCR ligation experiments, fluorescence imaging","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 1/2 / Moderate — direct lipid binding demonstrated in vitro, functional confirmation with PI3K inhibitors and mutagenesis, single lab","pmids":["21285350"],"is_preprint":false},{"year":2011,"finding":"SDF-1 (CXCL12) stimulation via CXCR4 causes RasGRP1 to localize to the plasma membrane (activating K-Ras) and to the Golgi (activating N-Ras) through a novel signaling complex containing RasGRP1, Gαi2, and ZAP-70. This translocation does not require the DAG-binding domain for localization but does require it for activity. CXCR4-mediated RasGRP1 mobilization also requires TCR expression.","method":"RasGRP1 RNAi knockdown in human T cells, co-immunoprecipitation of RasGRP1/Gαi2/ZAP-70 complex, confocal microscopy of RasGRP1 localization, Ras isoform activation assays (K-Ras vs N-Ras), migration assays","journal":"Journal of immunology","confidence":"Medium","confidence_rationale":"Tier 2/3 / Moderate — co-IP of novel complex, compartment-specific Ras activation demonstrated, RNAi functional phenotype, single lab","pmids":["21856938"],"is_preprint":false},{"year":2011,"finding":"PKC-δ and RasGRP1 together mediate a Ca2+-driven pathway for proapoptotic ERK activation in B cells that is biochemically distinct from DAG-driven ERK activation. This pathway depends on STIM1 concentration (which controls Ca2+ entry) and is required for negative selection of autoreactive B cells.","method":"PKC-δ knockout mice, RasGRP1 and STIM1 knockdown/overexpression, ERK phosphorylation assays distinguishing Ca2+- vs DAG-driven activation, B cell apoptosis assays","journal":"Nature immunology","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple genetic models (KO mice, overexpression, knockdown) with biochemically distinct pathway readouts","pmids":["21441934"],"is_preprint":false},{"year":2013,"finding":"Crystal structure of a RasGRP1 fragment reveals an autoinhibited conformation in which the Ras-binding site is blocked by an interdomain linker and the membrane-interaction surface is buried in a dimerization interface stabilized by the C-terminal oligomerization domain. NMR shows that calcium binding to the regulatory module induces conformational changes incompatible with the inactive assembly, providing the structural basis for calcium-dependent activation.","method":"X-ray crystallography, NMR spectroscopy, structure-guided mutagenesis","journal":"eLife","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure plus NMR with functional validation; rigorous structural study","pmids":["23908768"],"is_preprint":false},{"year":2013,"finding":"RasGRP1 overexpression in T-ALL activates Ras downstream of cytokine receptors (IL-2, IL-7, IL-9) through a mechanism that does not require acute PLCγ-dependent DAG generation but relies on baseline DAG levels. Overexpression of RasGRP1 constitutively increases the GTP-loading rate of Ras, establishing a high flux through the RasGTP/GDP cycle that is counterbalanced by RasGAP activity.","method":"Ras-GTP pull-down assays, multiple RasGTP/GDP flux assays, PLCγ inhibitor experiments, cytokine stimulation in T-ALL vs normal thymocytes","journal":"Science signaling","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — three distinct Ras-GTP loading assays plus PLCγ independence experiments; single lab","pmids":["23532335"],"is_preprint":false},{"year":2013,"finding":"RasGRP1 missense mutation in the EF-hand (Anaef allele) reduces Ras-ERK activation but causes elevated tonic mTOR-S6K signaling and CD44 overexpression on naïve T cells. The mTOR-dependent T cell dysregulation and autoantibody production in Rasgrp1Anaef mice are rescued by a reduction-of-function Mtor mutation, placing RasGRP1 upstream of mTOR in tonic T cell signaling.","method":"ENU mutagenesis, Rasgrp1Anaef knock-in mice, Rasgrp1Anaef x Mtorchino double-mutant mice, S6K phosphorylation assays, T cell subset analysis","journal":"eLife","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic epistasis with double-mutant rescue establishes pathway position; multiple orthogonal assays in a well-controlled mouse model","pmids":["24336796"],"is_preprint":false},{"year":2015,"finding":"RasGRP1 creates a negative feedback loop that limits proliferative EGFR-SOS1-Ras signals in colorectal cancer cells. RasGRP1 and SOS1 act in functional opposition downstream of EGFR; genetic Rasgrp1 depletion in mice with activating KRas mutation or Apc mutation exacerbates Ras-ERK signaling and cell proliferation.","method":"Rasgrp1 conditional knockout in KrasG12D and Apc-mutant mice, EGFR stimulation assays, ERK phosphorylation, intestinal organoid proliferation assays","journal":"Nature cell biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — two independent genetic mouse models with consistent mechanistic outcomes; functional opposition with SOS1 demonstrated","pmids":["26005835"],"is_preprint":false},{"year":2015,"finding":"RasGRP1 overexpression in T-ALL increases basal Ras GTP-loading flux and enables IL-2/7/9 cytokine receptor signals to activate the Ras-Akt pathway. In these leukemic cells, cytokine stimulation decreases RasGAP activity rather than increasing GEF activity, revealing that the balance between RasGRP1-driven GTP loading and RasGAP-driven hydrolysis determines net oncogenic Ras signaling.","method":"Ras-GTP pull-down, nucleotide exchange rate assays, Akt/ERK phosphorylation assays, cytokine stimulation with PLCγ inhibitor controls","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple mechanistic assays in T-ALL cells, single lab","pmids":["26549032"],"is_preprint":false},{"year":2016,"finding":"RASGRP1 deficiency in humans causes combined immunodeficiency with impaired ERK phosphorylation in T and B cells, defective NK cell cytotoxicity with impaired granule convergence and actin accumulation, and decreased RhoA GTPase activation. Interaction proteomics identified DYNLL1 (dynein light chain) as a RasGRP1-interacting protein, linking RasGRP1 to cytoskeletal dynamics.","method":"Homozygosity mapping, exome sequencing, wild-type RASGRP1 rescue, interaction proteomics (Co-IP/MS), ERK phosphorylation assays, RhoA activation assay, NK cytotoxicity assay","journal":"Nature immunology","confidence":"High","confidence_rationale":"Tier 2 / Strong — human loss-of-function with WT rescue, interaction proteomics identifying DYNLL1, functional RhoA and cytoskeletal readouts","pmids":["27776107"],"is_preprint":false},{"year":2016,"finding":"RasGRP1 is an HSP90 client protein. HDAC inhibitor-induced HSP90 acetylation causes release and proteasomal degradation of RasGRP1 (and CRAF), leading to MAPK pathway downregulation and BIM upregulation in lymphoma cells. RasGRP1 siRNA mimics the pro-apoptotic effects of HDAC inhibitors.","method":"Co-immunoprecipitation of HSP90-RasGRP1 complex, HDAC inhibitor treatment, siRNA knockdown of RasGRP1, Western blotting for protein stability, BIM/apoptosis assays in vivo and in vitro","journal":"Leukemia","confidence":"Medium","confidence_rationale":"Tier 2/3 / Moderate — HSP90 client status confirmed by co-IP and degradation assay, functional consequences validated with siRNA, single lab","pmids":["27890930"],"is_preprint":false},{"year":2017,"finding":"His212 in RasGRP1 functions as a pH sensor that alters the balance between inactive and active conformations. Structural comparison of autoinhibited RasGRP1 and active RasGRP4:H-Ras/RasGRP2:Rap1b complexes shows that the transition involves rearrangement of an interdomain linker at a fulcrum where His212 is located. Charge alteration at His212 via SNP variants alters signaling activity and plasma membrane recruitment.","method":"Crystal structure comparison, NMR analysis of pH-dependent conformational changes, functional assays of His212 SNP variants (plasma membrane recruitment, Ras signaling)","journal":"eLife","confidence":"High","confidence_rationale":"Tier 1 / Strong — structural analysis (crystal structures + NMR) with functional validation of specific residue variants","pmids":["28952923"],"is_preprint":false},{"year":2018,"finding":"SRSF1 (serine/arginine-rich splicing factor 1) directly binds exon 11 of RASGRP1 pre-mRNA and promotes inclusion of exon 11, maintaining wild-type RASGRP1 protein expression. Silencing SRSF1 in healthy T cells increases the ratio of alternatively spliced (exon-11-skipped) to wild-type RASGRP1 and decreases RASGRP1 protein; conversely, overexpression of SRSF1 in SLE T cells restores RASGRP1 protein and downstream DNMT1/IL-2 expression.","method":"Oligonucleotide-protein pulldown assay (direct binding), SRSF1 siRNA and overexpression, RT-PCR splicing analysis, Western blotting","journal":"Arthritis & rheumatology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct RNA-protein binding demonstrated, gain- and loss-of-function with splice isoform quantification, single lab","pmids":["29905030"],"is_preprint":false},{"year":2019,"finding":"An intronic enhancer in RASGRP1 (containing SNP rs11631591) drives cell-type-specific RASGRP1 transcription in T lymphocytes. The risk allele of rs11631591 binds hnRNP-K, and inhibition of hnRNP-K in Jurkat and primary T cells downregulates RASGRP1 and ERK/MAPK signaling.","method":"Luciferase reporter assay (allele-specific enhancer activity), EMSA, mass spectrometry identification of hnRNP-K, ChIP-qPCR, hnRNP-K inhibition with functional readout","journal":"Frontiers in immunology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple biochemical methods validating enhancer and transcription factor, single lab","pmids":["31164884"],"is_preprint":false},{"year":2020,"finding":"RUNX1 and its cofactor CBFB bind a RASGRP1 intrinsic enhancer and transcriptionally activate RASGRP1 expression. CRISPR-Cas9 disruption of this enhancer reduces RasGRP1 protein levels, and reduced RUNX1 expression in autoimmune patient CD4+ T cells correlates with decreased RASGRP1 levels.","method":"CRISPR-Cas9 enhancer disruption, ChIP-seq H3K27ac profiling, RUNX1/CBFB binding confirmation, RASGRP1 expression and ERK signaling assays","journal":"European journal of immunology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — CRISPR enhancer KO with functional expression readout, epigenetic data supporting mechanism, single lab","pmids":["33065764"],"is_preprint":false},{"year":2020,"finding":"RasGRP1 promotes L-DOPA-induced dyskinesia (LID) in the striatum by activating ERK and mTOR signaling. RasGRP1 acts as a GEF for Rheb (the activator of mTOR kinase complex) in addition to its canonical Ras GEF activity. RasGRP1 knockout mice show dramatically reduced LID without impaired L-DOPA therapeutic effects.","method":"RasGRP1 knockout mice in parkinsonian model, L-DOPA dyskinesia behavioral assays, ERK and mTOR phosphorylation in striatum, tandem mass spectrometry proteomics for downstream targets","journal":"Science advances","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — knockout mouse with defined behavioral and biochemical phenotypes, novel Rheb GEF activity supported by proteomics but would benefit from direct reconstitution","pmids":["32426479"],"is_preprint":false},{"year":2010,"finding":"Phorbol ester stimulation of RasGRP1 in renal distal convoluted tubule cells activates the Ras-ERK pathway and suppresses the surface expression and function of the sodium-chloride cotransporter (NCC) via NCC ubiquitination and dynamin-dependent endocytosis. RasGRP1 gene silencing prevents phorbol ester-induced Ras activation, ERK activation, NCC ubiquitination, and endocytosis.","method":"RasGRP1 siRNA knockdown, biotinylation assay of surface NCC, internalization assay, dynamin dominant-negative construct, ubiquitin immunoprecipitation, radiotracer NCC activity assay","journal":"American journal of physiology. Renal physiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple assays establishing RasGRP1→ERK→ubiquitination→endocytosis mechanism, single lab","pmids":["20392800"],"is_preprint":false},{"year":2007,"finding":"Phorbol ester activates RasGRP1 in renal distal convoluted tubule cells, which in turn activates H-Ras and ERK1/2 MAPK in a PKC-independent manner, leading to suppression of NCC function and surface expression. RasGRP1 gene silencing prevents all of these effects, identifying RasGRP1 as the critical mediator of phorbol ester action on NCC.","method":"RasGRP1 siRNA knockdown, PKC/MAPK inhibitor experiments, 22Na+ radiotracer NCC activity assay, biotinylation of surface NCC, H-Ras activation assay","journal":"Proceedings of the National Academy of Sciences","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — RNAi-based mechanism dissection with PKC independence shown and Ras isoform specificity established, single lab","pmids":["18077438"],"is_preprint":false},{"year":2016,"finding":"RasGRP1 interacts with and stabilizes Rhes (Ras homolog enriched in striatum), increasing Rhes synaptic accumulation in the striatum. RasGRP1 affects the composition of the amphetamine-induced Rhes interactome (Rhesactome), including proteins associated with neuropsychiatric disorders. Partial depletion of RasGRP1 attenuates the enhanced locomotor response to amphetamine seen in Rhes-heterozygous mice.","method":"Rhes-heterozygous and RasGRP1 knockout mouse models, proteomic analysis of striatal Rhes-interactome, locomotor behavioral assays, western blot for Rhes synaptic localization","journal":"Science signaling","confidence":"Medium","confidence_rationale":"Tier 2/3 / Moderate — proteomics plus behavioral genetics establish RasGRP1-Rhes interaction and functional consequence, single lab","pmids":["27902448"],"is_preprint":false},{"year":2009,"finding":"In B cells, RasGRP1 activates a proapoptotic pathway involving PKC/Ras-Raf-MEK-ERK signaling leading to phosphorylation of the BH3-only protein Bim by ERK on sites associated with increased apoptotic activity, followed by Bak-Bax complex formation and mitochondrial membrane permeabilization. This apoptosis can be suppressed by Bim downregulation or Bcl-2 overexpression.","method":"DAG analogue stimulation, in vitro ERK-Bim kinase assay, Bim siRNA, Bcl-2 overexpression, Bak-Bax co-immunoprecipitation, mitochondrial membrane potential assay","journal":"Experimental hematology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vitro kinase assay for ERK-Bim phosphorylation, multiple pathway inhibitors and genetic rescue experiments, single lab","pmids":["19100522"],"is_preprint":false},{"year":2004,"finding":"SKAP55 co-immunoprecipitates with RasGRP1 via its C-terminus; this interaction is enhanced by tyrosine phosphorylation of SKAP55. Overexpression of SKAP55 disrupts TCR-to-Ras-ERK signaling, and this effect requires the RasGRP1-binding C-terminus of SKAP55; constitutively active Ras or Raf-1 overcome SKAP55 overexpression, placing the SKAP55-RasGRP1 interaction upstream of Ras.","method":"Co-immunoprecipitation, SKAP55 domain deletion constructs, TCR-induced ERK and AP-1 reporter assays, constitutively active Ras/Raf rescue","journal":"Molecular immunology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single co-IP with functional overexpression data, no reciprocal pull-down or in vitro reconstitution","pmids":["17658605"],"is_preprint":false}],"current_model":"RasGRP1 is a DAG- and calcium-regulated Ras guanine nucleotide exchange factor that is maintained in an autoinhibited state (crystal structure defined) and activated by DAG-driven membrane recruitment via its C1 domain and/or phosphoinositide binding by its PT domain; once membrane-localized, RasGRP1 catalyzes GDP-for-GTP exchange on Ras at the plasma membrane or Golgi apparatus, directly activates Ras and—by generating RasGTP that primes the allosteric pocket of SOS—creates a positive feedback loop for robust lymphocyte Ras-ERK signaling downstream of TCR/BCR-PLCγ-DAG; RasGRP1 activity is tuned by PKC-mediated phosphorylation of Thr184, alternative splicing of its EF-hand, pH-sensing by His212, and suppression by SKAP55 binding, while its expression is transcriptionally controlled by RUNX1/CBFB and post-transcriptionally by SRSF1-dependent splicing, and it additionally functions as a GEF for Rheb to activate mTOR in the striatum and interfaces with cytoskeletal dynamics through DYNLL1."},"narrative":{"mechanistic_narrative":"RASGRP1 is a diacylglycerol (DAG)- and calcium-regulated guanine nucleotide exchange factor (GEF) that couples antigen-receptor and phospholipase-C signaling to Ras-ERK activation, and it is the essential, non-redundant link between TCR/DAG signaling and Ras during thymocyte maturation [PMID:9582122, PMID:11017103]. Its activation is governed by membrane recruitment: a high-affinity C1 domain binds DAG/phorbol esters and drives translocation to membranes, while a Plasma membrane Targeter (PT) domain binds PI3K-generated phosphoinositides, and these inputs are countered by a Suppressor-of-PT domain and modulated by an EF-hand whose alternative splicing tunes targeting [PMID:9819387, PMID:10779365, PMID:17567957, PMID:21285350]. In the resting state RASGRP1 is autoinhibited, with the Ras-binding site blocked by an interdomain linker and the membrane surface buried in a dimerization interface; calcium binding and a His212 pH-sensing fulcrum drive the conformational transition to the active form [PMID:23908768, PMID:28952923]. Once membrane-localized, RASGRP1 catalyzes nucleotide exchange on Ras at both the plasma membrane and the Golgi—a Golgi compartment specificity unique to the RasGRP family—and amplifies signaling by generating RasGTP that primes the allosteric pocket of SOS, establishing a positive feedback loop that explains its dominance in lymphocytes [PMID:12845332, PMID:12782630, PMID:17283063]. Activity is further tuned by PKC-dependent Thr184 phosphorylation, DGKalpha-mediated DAG clearance, and negative regulation by the adaptor SKAP55, and expression is controlled transcriptionally by RUNX1/CBFB and an hnRNP-K-bound enhancer and post-transcriptionally by SRSF1-dependent exon-11 splicing [PMID:11919165, PMID:15899849, PMID:18320039, PMID:29905030, PMID:31164884, PMID:33065764]. Beyond canonical Ras signaling, RASGRP1 acts as a GEF for Rheb to activate mTOR in striatal neurons and interfaces with cytoskeletal dynamics via DYNLL1 [PMID:24336796, PMID:27776107, PMID:32426479]. Human biallelic loss of RASGRP1 causes a combined immunodeficiency with impaired T/B cell ERK signaling and defective NK cytotoxicity [PMID:27776107].","teleology":[{"year":1998,"claim":"Established RASGRP1 as a Ras GEF and identified DAG-driven membrane translocation through its C1 domain as the activation mechanism, defining the protein's core biochemical logic.","evidence":"NIH 3T3 transformation, subcellular fractionation, and domain-deletion/substitution mutagenesis with GEF and MAPK readouts","pmids":["9582122","9819387"],"confidence":"High","gaps":["Did not resolve which Ras isoforms or compartments are engaged in physiological cells","Activation mechanism studied in fibroblasts, not lymphocytes"]},{"year":2000,"claim":"Demonstrated that RASGRP1 is the essential, non-redundant GEF linking TCR/PLC-gamma/DAG signaling to Ras and is required for mature thymocyte development, moving it from a transforming protein to a physiological immune signaling node.","evidence":"Antibody inhibition and overexpression in Jurkat cells plus a targeted knockout mouse with thymocyte phenotyping and Ras activation assays","pmids":["10807788","11017103"],"confidence":"High","gaps":["Did not define the spatial site of Ras activation","Mechanism of how DAG signal is converted to sustained Ras output unresolved"]},{"year":2000,"claim":"Quantified the C1 domain as a high-affinity DAG/phorbol ester receptor distinct from PKC, establishing the ligand-binding basis of recruitment.","evidence":"Radioligand binding ([3H]PDBu) with competition and cofactor analysis","pmids":["10779365"],"confidence":"High","gaps":["In vitro binding did not address membrane discrimination in cells"]},{"year":2003,"claim":"Revealed compartmentalized Ras signaling: RASGRP1 activates Ras at the Golgi, a localization unique to the RasGRP family, with calcium positively regulating Golgi Ras while distinct GAPs negatively regulate plasma membrane Ras.","evidence":"Live-cell imaging of GFP-tagged RasGRP1 and Ras biosensors with compartment-resolved activation assays in Jurkat cells; systematic GEF comparison","pmids":["12845332","12782630"],"confidence":"High","gaps":["How C1 versus other domains select internal versus plasma membrane was not fully resolved","Functional consequence of Golgi versus PM Ras pools unclear"]},{"year":2005,"claim":"Defined a DAG-PKC-RasGRP1-Ras-ERK feedback circuit by identifying Thr184 phosphorylation by novel PKC as a positive regulatory event.","evidence":"RasGRP1-deficient Jurkat clones, RNAi, phospho-specific antibodies, and PKC inhibitors","pmids":["15899849"],"confidence":"High","gaps":["Precise effect of Thr184 phosphorylation on conformation or localization not structurally defined"]},{"year":2007,"claim":"Showed RASGRP1 amplifies Ras signaling by priming the SOS allosteric pocket with RasGTP, explaining its dominance in initiating lymphocyte Ras-ERK feedback.","evidence":"Genetic knockout/reconstitution in Jurkat and DT40 cells with allosteric SOS mutants and RasV12C40 substitution","pmids":["17283063"],"confidence":"High","gaps":["Quantitative kinetics of the RasGRP1-SOS handoff in vivo not established"]},{"year":2007,"claim":"Dissected the membrane-targeting machinery, defining cooperative C1, PT, and SuPT domains and the C-terminal tail as determinants of receptor-induced localization.","evidence":"Domain deletion/mutational analysis with live imaging in B cells and fibroblasts, and tail-deleted knock-in mice","pmids":["17567957","22719950"],"confidence":"Medium","gaps":["Single-lab studies","Molecular partners mediating tail-dependent trafficking unidentified"]},{"year":2009,"claim":"Established that EF1, independent of bulk calcium flux, and its alternative splicing modulate plasma membrane targeting by counteracting the SuPT domain, with the GEF Ras-binding site itself feeding back into localization.","evidence":"EF-hand mutagenesis, splice isoform expression, calcium chelation, and live imaging in B cells","pmids":["19168098"],"confidence":"Medium","gaps":["Single lab","Physiological splice ratios and their regulation not quantified here"]},{"year":2011,"claim":"Connected PI3K signaling to RASGRP1 recruitment by demonstrating direct phosphoinositide binding by a basic/hydrophobic cluster in the PT domain.","evidence":"Lipid vesicle binding assays, PI3K inhibitors, cluster mutagenesis, and BCR ligation imaging","pmids":["21285350"],"confidence":"Medium","gaps":["Single lab","Relative contribution of PT/phosphoinositide versus C1/DAG in vivo not quantified"]},{"year":2011,"claim":"Identified a calcium-driven, DAG-independent RASGRP1/PKC-delta proapoptotic ERK pathway required for negative selection of autoreactive B cells, distinguishing it biochemically from canonical DAG-driven ERK.","evidence":"PKC-delta knockout mice, STIM1 and RasGRP1 manipulation, and pathway-resolved ERK and apoptosis assays","pmids":["21441934"],"confidence":"High","gaps":["How calcium converts ERK output to proapoptotic rather than proliferative not fully mechanistic"]},{"year":2013,"claim":"Provided the structural basis for autoinhibition and calcium-dependent activation, showing the Ras-binding site is blocked and the membrane surface buried in a dimerization interface that calcium disrupts.","evidence":"X-ray crystallography, NMR, and structure-guided mutagenesis","pmids":["23908768"],"confidence":"High","gaps":["Full-length protein with all regulatory domains not crystallized","Membrane-bound active conformation not directly visualized"]},{"year":2013,"claim":"Revealed an oncogenic mode in T-ALL where RASGRP1 overexpression raises basal Ras GTP-loading flux, enabling cytokine receptors to drive Ras independently of acute PLC-gamma/DAG.","evidence":"Multiple Ras-GTP flux assays and PLC-gamma inhibitor experiments in T-ALL versus normal thymocytes","pmids":["23532335"],"confidence":"Medium","gaps":["Single lab","Mechanism enabling DAG-independent activation at baseline DAG unclear"]},{"year":2013,"claim":"Placed RASGRP1 upstream of mTOR in tonic T cell signaling using genetic epistasis, showing an EF-hand mutant uncouples reduced Ras-ERK from elevated mTOR-S6K activity and autoimmunity.","evidence":"ENU-derived Rasgrp1(Anaef) knock-in crossed to an Mtor reduction-of-function allele with S6K and T cell subset readouts","pmids":["24336796"],"confidence":"High","gaps":["Direct biochemical link from RASGRP1 to mTOR not defined in this study"]},{"year":2015,"claim":"Defined a context-dependent negative-feedback role: in epithelial/colorectal cancer cells RASGRP1 opposes EGFR-SOS1-Ras signaling, contrasting with its amplifying role in lymphocytes.","evidence":"Rasgrp1 conditional knockout in KrasG12D and Apc-mutant mice with EGFR stimulation and organoid proliferation assays","pmids":["26005835"],"confidence":"High","gaps":["Molecular basis of the RASGRP1-SOS1 opposition not structurally resolved"]},{"year":2015,"claim":"Showed that net oncogenic Ras output in RASGRP1-overexpressing T-ALL is set by the balance between RASGRP1-driven GTP loading and RasGAP-driven hydrolysis, with cytokines acting by decreasing GAP activity.","evidence":"Ras-GTP pull-down, exchange-rate assays, and Akt/ERK readouts with PLC-gamma controls","pmids":["26549032"],"confidence":"Medium","gaps":["Single lab","Identity of the cytokine-regulated GAP not defined"]},{"year":2016,"claim":"Identified human RASGRP1 loss-of-function as a cause of combined immunodeficiency and linked RASGRP1 to cytoskeletal/NK cell function via RhoA activation and a DYNLL1 interaction.","evidence":"Homozygosity mapping, exome sequencing, WT rescue, interaction proteomics, and RhoA/NK cytotoxicity assays","pmids":["27776107"],"confidence":"High","gaps":["How RASGRP1 controls RhoA and DYNLL1-dependent cytoskeletal events mechanistically unresolved"]},{"year":2016,"claim":"Showed RASGRP1 stabilizes the striatal GTPase Rhes and shapes its interactome, extending RASGRP1 function into neuronal/behavioral regulation.","evidence":"Rhes-heterozygous and RasGRP1 knockout mice, striatal Rhes-interactome proteomics, and locomotor behavioral assays","pmids":["27902448"],"confidence":"Medium","gaps":["Single lab","Whether stabilization reflects direct GEF/binding activity not resolved"]},{"year":2017,"claim":"Defined His212 as a pH-sensing fulcrum controlling the autoinhibited-to-active transition, with SNP variants altering signaling and membrane recruitment.","evidence":"Crystal structure comparison, NMR of pH-dependent changes, and functional assays of His212 variants","pmids":["28952923"],"confidence":"High","gaps":["Physiological contexts where intracellular pH gates RASGRP1 not established"]},{"year":2018,"claim":"Established post-transcriptional control of RASGRP1 by SRSF1, which binds exon 11 and promotes its inclusion to maintain wild-type protein, relevant to lupus T cell dysfunction.","evidence":"Oligonucleotide-protein pulldown, SRSF1 loss/gain of function, splicing RT-PCR, and Western blot in healthy and SLE T cells","pmids":["29905030"],"confidence":"Medium","gaps":["Single lab","Functional difference between exon-11-included and -skipped isoforms not biochemically defined"]},{"year":2019,"claim":"Identified an intronic enhancer SNP whose risk allele binds hnRNP-K to drive T-cell-specific RASGRP1 transcription, linking genetic variation to ERK/MAPK signaling.","evidence":"Allele-specific luciferase, EMSA, mass spectrometry, ChIP-qPCR, and hnRNP-K inhibition with functional readouts","pmids":["31164884"],"confidence":"Medium","gaps":["Single lab","In vivo contribution of the enhancer to autoimmunity not tested"]},{"year":2020,"claim":"Defined RUNX1/CBFB transcriptional activation of RASGRP1 via an intrinsic enhancer, connecting reduced RUNX1 to lowered RASGRP1 in autoimmune T cells.","evidence":"CRISPR-Cas9 enhancer disruption, H3K27ac ChIP-seq, RUNX1/CBFB binding confirmation, and expression/ERK assays","pmids":["33065764"],"confidence":"Medium","gaps":["Single lab","Interplay with the hnRNP-K enhancer not integrated"]},{"year":2020,"claim":"Demonstrated a non-Ras catalytic function: RASGRP1 acts as a Rheb GEF to drive ERK/mTOR-dependent L-DOPA-induced dyskinesia in the striatum.","evidence":"RasGRP1 knockout in a parkinsonian model with dyskinesia behavior, striatal ERK/mTOR phosphorylation, and proteomics","pmids":["32426479"],"confidence":"Medium","gaps":["Direct reconstitution of Rheb GEF activity not performed","Single lab"]},{"year":2010,"claim":"Extended RASGRP1 signaling to renal epithelium, where it drives Ras-ERK-dependent ubiquitination and dynamin-dependent endocytosis of the NCC cotransporter.","evidence":"RasGRP1 siRNA, surface NCC biotinylation, internalization and ubiquitin assays, and dominant-negative dynamin in distal convoluted tubule cells","pmids":["20392800","18077438"],"confidence":"Medium","gaps":["Single lab","Physiological trigger of RASGRP1 in renal tubule in vivo unclear"]},{"year":null,"claim":"How the multiple regulatory inputs (C1/DAG, PT/phosphoinositide, EF-hand/calcium, His212/pH, Thr184 phosphorylation) are integrated on a full-length, membrane-bound RASGRP1 to set compartment-specific Ras versus Rheb output remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No full-length membrane-bound active structure","Quantitative integration of the regulatory inputs not modeled","Direct biochemical demonstration of Rheb GEF activity outstanding"]}],"mechanism_profile":{"molecular_activity":[],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[1,13,15]},{"term_id":"GO:0005794","term_label":"Golgi apparatus","supporting_discovery_ids":[6,7,8]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0,6,10]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[3,17,23]}],"complexes":[],"partners":["SOS1","SKAP55","DYNLL1","RHES","ZAP-70","GNAI2","HSP90"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"O95267","full_name":"RAS guanyl-releasing protein 1","aliases":["Calcium and DAG-regulated guanine nucleotide exchange factor II","CalDAG-GEFII","Ras guanyl-releasing protein"],"length_aa":797,"mass_kda":90.4,"function":"Functions as a calcium- and diacylglycerol (DAG)-regulated nucleotide exchange factor specifically activating Ras through the exchange of bound GDP for GTP (PubMed:15899849, PubMed:23908768, PubMed:27776107, PubMed:29155103). Activates the Erk/MAP kinase cascade (PubMed:15899849). Regulates T-cell/B-cell development, homeostasis and differentiation by coupling T-lymphocyte/B-lymphocyte antigen receptors to Ras (PubMed:10807788, PubMed:12839994, PubMed:27776107, PubMed:29155103). Regulates NK cell cytotoxicity and ITAM-dependent cytokine production by activation of Ras-mediated ERK and JNK pathways (PubMed:19933860). Functions in mast cell degranulation and cytokine secretion, regulating FcERI-evoked allergic responses. May also function in differentiation of other cell types (PubMed:12845332)","subcellular_location":"Cytoplasm, cytosol; Cell membrane; Golgi apparatus membrane; Endoplasmic reticulum membrane","url":"https://www.uniprot.org/uniprotkb/O95267/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/RASGRP1","classification":"Not Classified","n_dependent_lines":6,"n_total_lines":1208,"dependency_fraction":0.004966887417218543},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"CEP164","stoichiometry":0.2},{"gene":"HSPA4L","stoichiometry":0.2},{"gene":"RAB3D","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/RASGRP1","total_profiled":1310},"omim":[{"mim_id":"618534","title":"IMMUNODEFICIENCY 64 WITH LYMPHOPROLIFERATION; IMD64","url":"https://www.omim.org/entry/618534"},{"mim_id":"614581","title":"MONOCYTE-TO-MACROPHAGE DIFFERENTIATION-ASSOCIATED PROTEIN 2; MMD2","url":"https://www.omim.org/entry/614581"},{"mim_id":"612840","title":"LEUKOCYTE ADHESION DEFICIENCY, TYPE III; LAD3","url":"https://www.omim.org/entry/612840"},{"mim_id":"607943","title":"RAS p21 PROTEIN ACTIVATOR 4; RASA4","url":"https://www.omim.org/entry/607943"},{"mim_id":"607901","title":"FERM DOMAIN-CONTAINING KINDLIN 3; FERMT3","url":"https://www.omim.org/entry/607901"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Cytosol","reliability":"Supported"},{"location":"Plasma membrane","reliability":"Additional"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in many","driving_tissues":[{"tissue":"brain","ntpm":23.3},{"tissue":"lymphoid tissue","ntpm":35.6},{"tissue":"retina","ntpm":16.6}],"url":"https://www.proteinatlas.org/search/RASGRP1"},"hgnc":{"alias_symbol":["CalDAG-GEFII","RASGRP"],"prev_symbol":[]},"alphafold":{"accession":"O95267","domains":[{"cath_id":"1.20.870.10","chopping":"42-184","consensus_level":"high","plddt":81.6756,"start":42,"end":184},{"cath_id":"1.10.840.10","chopping":"200-350_399-432","consensus_level":"high","plddt":90.2487,"start":200,"end":432},{"cath_id":"1.10.238.10","chopping":"462-538","consensus_level":"medium","plddt":79.204,"start":462,"end":538},{"cath_id":"3.30.60.20","chopping":"539-593","consensus_level":"medium","plddt":86.3347,"start":539,"end":593}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/O95267","model_url":"https://alphafold.ebi.ac.uk/files/AF-O95267-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-O95267-F1-predicted_aligned_error_v6.png","plddt_mean":71.69},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=RASGRP1","jax_strain_url":"https://www.jax.org/strain/search?query=RASGRP1"},"sequence":{"accession":"O95267","fasta_url":"https://rest.uniprot.org/uniprotkb/O95267.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/O95267/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/O95267"}},"corpus_meta":[{"pmid":"9582122","id":"PMC_9582122","title":"RasGRP, 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DAG analog treatment caused sustained Ras-ERK activation and membrane partitioning of RasGRP1; deletion of the DAG-binding domain abolished both membrane recruitment and sustained signaling, establishing that DAG-driven membrane translocation is the primary activation mechanism.\",\n      \"method\": \"Cell transformation assays in NIH 3T3 fibroblasts, subcellular fractionation, domain deletion mutagenesis, Ras-GTP assays\",\n      \"journal\": \"Science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — original characterization with in vitro GEF assay, domain deletion mutagenesis, and multiple functional readouts; replicated independently in same year\",\n      \"pmids\": [\"9582122\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1998,\n      \"finding\": \"The C1 domain of RasGRP1 is required for transforming activity; deletion of the C1 domain or an adjacent basic-amino-acid cluster abolished transformation and MAP kinase activation. Replacement of the C1 domain with a membrane-targeting prenylation signal or a PKC C1 domain restored activity, confirming that membrane recruitment via the C1 domain is the mechanistic basis of RasGRP1 activation. Phorbol ester stimulates C1-domain-dependent translocation of RasGRP1 to cell membranes.\",\n      \"method\": \"NIH 3T3 transformation assay, C1-domain deletion and substitution mutagenesis, MAP kinase activation assay, confocal microscopy of GFP-tagged protein\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — domain mutagenesis with functional rescue, multiple orthogonal assays, independent replication of core findings\",\n      \"pmids\": [\"9819387\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"RasGRP1 is required for TCR-induced Ras activation in T cells. A PLC-γ1 inhibitor reduced TCR-stimulated Ras activation; anti-RasGRP1 antibodies inhibited Ras-guanyl nucleotide exchange activity in TCR-stimulated Jurkat cell membranes. Overexpression of RasGRP1 enhanced TCR-Ras-ERK signaling and IL-2 secretion in response to DAG analogues plus calcium ionophore, directly linking PLC-γ1/DAG to Ras through RasGRP1.\",\n      \"method\": \"Ras-GTP pull-down assay, antibody inhibition of GEF activity in membrane fractions, RasGRP1 overexpression in Jurkat T cells, ERK activation assay, IL-2 ELISA\",\n      \"journal\": \"Blood\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal biochemical methods (antibody inhibition, overexpression, GTP-loading assay) in T cells; replicated by knockout mouse study\",\n      \"pmids\": [\"10807788\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"RasGRP1 (RasGRP) knockout mice show normal numbers of immature thymocytes but a marked deficiency of mature single-positive (CD4+ and CD8+) thymocytes. Mutant thymocytes completely lack Ras signaling and proliferative responses to DAG analogs or TCR stimulation, establishing RasGRP1 as an essential and non-redundant link between TCR/DAG signaling and Ras activation in thymic development.\",\n      \"method\": \"Targeted gene knockout in mice, thymocyte FACS phenotyping, Ras activation assay, thymocyte proliferation assay\",\n      \"journal\": \"Nature immunology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean knockout with defined cellular and biochemical phenotype, replicated across multiple labs\",\n      \"pmids\": [\"11017103\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"The C1 domain of RasGRP1 binds phorbol esters with high affinity (Kd ~0.58 nM for [3H]PDBu), comparable to PKC. Lipid cofactor requirements differ from PKC; calcium does not affect phorbol ester binding to the C1-EF domain, establishing the C1 domain as the primary high-affinity DAG/phorbol ester receptor on RasGRP1.\",\n      \"method\": \"Radioligand binding assay ([3H]PDBu), competition binding with DAG analogs and PKC inhibitors, phospholipid cofactor requirement analysis\",\n      \"journal\": \"Molecular pharmacology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — quantitative in vitro binding assay with multiple ligands and controls; well-replicated biochemical finding\",\n      \"pmids\": [\"10779365\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"Expression of a catalytically inactive diacylglycerol kinase alpha (DGKα) in T cells leads to sustained membrane translocation of RasGRP1 and sustained MAPK activation following TCR or muscarinic receptor stimulation, demonstrating that DGKα-mediated DAG clearance controls the duration of RasGRP1 activation and downstream Ras/MAPK signaling.\",\n      \"method\": \"Expression of kinase-dead DGKα in T cell lines, time-course imaging of RasGRP1 translocation, MAPK activation assay, DAG measurement\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — dominant-negative approach with functional readout and mechanistic DAG measurement, single lab\",\n      \"pmids\": [\"11919165\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"In response to Src-dependent activation of PLCγ1, RasGRP1 translocates to the Golgi apparatus where it activates Ras. Calcium positively regulates Golgi Ras through RasGRP1, while the same messenger negatively regulates plasma membrane Ras via the GAP CAPRI, demonstrating compartmentalized Ras signaling through distinct regulatory mechanisms.\",\n      \"method\": \"Live-cell imaging of GFP-tagged RasGRP1 and Ras biosensors, dominant-negative and constitutively active construct expression, Ras activation assays in Jurkat T cells\",\n      \"journal\": \"Nature\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — live imaging combined with biochemical Ras activation assays and genetic manipulations; published in Nature with independent validation of Golgi Ras signaling\",\n      \"pmids\": [\"12845332\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"RasGRP family members are the only Ras activators that localize to and activate Ras at the Golgi. Ras activation at the plasma membrane and ER can be achieved by most GEFs, but GTP loading of Ras at the Golgi is specific to RasGRP proteins, establishing a basis for compartmentalized Ras signaling.\",\n      \"method\": \"Subcellular fractionation, confocal microscopy of GFP-tagged GEFs, Ras activation assays in different membrane compartments\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple GEFs compared systematically with colocalization and functional Ras activation assays; replicated by Bivona et al.\",\n      \"pmids\": [\"12782630\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"The C1 domains of RasGRP1 and PKCθ show distinct subcellular localization in living T lymphocytes despite high structural similarity, with RasGRP1 C1 domain preferentially accumulating at internal membranes (Golgi) following TCR triggering, while PKCθ C1 domain targets the plasma membrane. Overexpression of individual C1 domains can attenuate DAG-dependent signals from respective membranes, establishing these domains as functional DAG discriminators.\",\n      \"method\": \"Live-cell imaging with fluorescent C1 domain fusion proteins, pharmacological stimulation and TCR triggering, Ras activation reporter assays in Jurkat T cells\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — live imaging with functional consequences, single lab\",\n      \"pmids\": [\"15064353\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"RasGRP1 is required for optimal antigen receptor-triggered Ras-ERK activation in T cells, and relies on its DAG-binding domain for selective Erk kinase activation. Phosphorylation of threonine 184 (Thr184) in RasGRP1 correlates with ERK activation and requires novel PKC kinase activities. PKCθ activation is in turn dependent on RasGRP1, establishing a DAG-PKC-RasGRP1-Ras-ERK pathway with positive feedback.\",\n      \"method\": \"RasGRP1-deficient Jurkat T cell clones, RNAi knockdown, phospho-specific antibodies, domain deletion constructs, PKC pharmacological inhibitors\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple genetic and pharmacological approaches in T cells, site-specific phosphorylation identified, replicated in different systems\",\n      \"pmids\": [\"15899849\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"RasGRP1 orchestrates Ras signaling in two ways: (i) by directly activating Ras and (ii) by generating RasGTP that primes the allosteric pocket of SOS, enhancing SOS activity and creating a positive RasGTP-SOS feedback loop. Without RasGRP1, this loop cannot be initiated because SOS requires its own product (RasGTP) for allosteric activation, explaining RasGRP1 dominance in lymphocytes.\",\n      \"method\": \"Jurkat and DT40 B cell genetic knockouts and reconstitution, allosteric SOS mutants, RasV12C40 expression to substitute RasGRP function, Ras-GTP quantification\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — allosteric mechanism validated with structure-guided mutants, multiple cell lines, and genetic complementation\",\n      \"pmids\": [\"17283063\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"RasGRP1 is required for membrane translocation and activation; the tail domain (C-terminal ~200 residues) is essential for membrane trafficking of RasGRP1 following TCR stimulation, and its deletion abolishes ERK activation despite intact C1 and EF domains.\",\n      \"method\": \"Knock-in mice expressing tail-deleted RasGRP1, TCR stimulation assays, subcellular fractionation, ERK phosphorylation assay, FACS analysis\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — knock-in mouse model with direct localization and signaling readouts, single lab\",\n      \"pmids\": [\"22719950\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"The adaptor protein SKAP-55 binds RasGRP1 via its C-terminus in a manner enhanced by SKAP-55 tyrosine phosphorylation. This interaction negatively regulates the Ras-ERK pathway: SKAP-55 deficiency leads to increased RasGRP1 localization at the trans-Golgi network and hyper-activation of ERK following TCR stimulation.\",\n      \"method\": \"Co-immunoprecipitation, RNAi knockdown, SKAP-55 knockout T cells, confocal microscopy of RasGRP1 localization, ERK phosphorylation assay\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — co-IP binding demonstrated, knockout cells show RasGRP1 mis-localization and functional ERK phenotype, single lab\",\n      \"pmids\": [\"18320039\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"BCR-induced plasma membrane targeting of RasGRP1 requires cooperativity between three domains: the C1 domain (binds DAG generated by PLCγ2), the Plasma membrane Targeter (PT) domain (sufficient and essential for plasma membrane targeting), and the Suppressor of PT (SuPT) domain (attenuates constitutive PM localization). In fibroblasts, the PT domain is inactive, so the C1 domain directs RasGRP1 to internal membranes.\",\n      \"method\": \"Domain deletion and mutational analysis, live fluorescence imaging in B cell lines and fibroblasts, BCR ligation experiments\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — systematic domain dissection with multiple cell types and imaging, single lab\",\n      \"pmids\": [\"17567957\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"One EF-hand (EF1) of RasGRP1 is required for receptor-induced translocation to the plasma membrane in B cells by counteracting the SuPT domain, independently of antigen receptor-induced calcium flux. Alternative splicing of EF1 modulates RasGRP1 plasma membrane targeting. The GEF domain Ras-binding site is required for both PT- and C1-mediated membrane localizations, suggesting positive feedback from Ras engagement.\",\n      \"method\": \"EF-hand mutagenesis, alternative splice isoform expression, calcium chelator experiments, live-cell fluorescence imaging in B cell lines\",\n      \"journal\": \"Biochimica et biophysica acta\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — mutagenesis combined with live imaging and calcium independence experiments, single lab\",\n      \"pmids\": [\"19168098\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Phosphoinositide 3-kinase (PI3K) signaling controls plasma membrane targeting of RasGRP1. A basic/hydrophobic cluster within the PT domain of RasGRP1 binds directly to phosphoinositide-containing lipid vesicles via electrostatic interactions, and BCR ligation-induced PI3K activity generates plasma membrane phosphoinositides that recruit RasGRP1.\",\n      \"method\": \"Lipid vesicle binding assays, PI3K inhibitors, mutagenesis of basic/hydrophobic cluster, BCR ligation experiments, fluorescence imaging\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1/2 / Moderate — direct lipid binding demonstrated in vitro, functional confirmation with PI3K inhibitors and mutagenesis, single lab\",\n      \"pmids\": [\"21285350\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"SDF-1 (CXCL12) stimulation via CXCR4 causes RasGRP1 to localize to the plasma membrane (activating K-Ras) and to the Golgi (activating N-Ras) through a novel signaling complex containing RasGRP1, Gαi2, and ZAP-70. This translocation does not require the DAG-binding domain for localization but does require it for activity. CXCR4-mediated RasGRP1 mobilization also requires TCR expression.\",\n      \"method\": \"RasGRP1 RNAi knockdown in human T cells, co-immunoprecipitation of RasGRP1/Gαi2/ZAP-70 complex, confocal microscopy of RasGRP1 localization, Ras isoform activation assays (K-Ras vs N-Ras), migration assays\",\n      \"journal\": \"Journal of immunology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2/3 / Moderate — co-IP of novel complex, compartment-specific Ras activation demonstrated, RNAi functional phenotype, single lab\",\n      \"pmids\": [\"21856938\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"PKC-δ and RasGRP1 together mediate a Ca2+-driven pathway for proapoptotic ERK activation in B cells that is biochemically distinct from DAG-driven ERK activation. This pathway depends on STIM1 concentration (which controls Ca2+ entry) and is required for negative selection of autoreactive B cells.\",\n      \"method\": \"PKC-δ knockout mice, RasGRP1 and STIM1 knockdown/overexpression, ERK phosphorylation assays distinguishing Ca2+- vs DAG-driven activation, B cell apoptosis assays\",\n      \"journal\": \"Nature immunology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple genetic models (KO mice, overexpression, knockdown) with biochemically distinct pathway readouts\",\n      \"pmids\": [\"21441934\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Crystal structure of a RasGRP1 fragment reveals an autoinhibited conformation in which the Ras-binding site is blocked by an interdomain linker and the membrane-interaction surface is buried in a dimerization interface stabilized by the C-terminal oligomerization domain. NMR shows that calcium binding to the regulatory module induces conformational changes incompatible with the inactive assembly, providing the structural basis for calcium-dependent activation.\",\n      \"method\": \"X-ray crystallography, NMR spectroscopy, structure-guided mutagenesis\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure plus NMR with functional validation; rigorous structural study\",\n      \"pmids\": [\"23908768\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"RasGRP1 overexpression in T-ALL activates Ras downstream of cytokine receptors (IL-2, IL-7, IL-9) through a mechanism that does not require acute PLCγ-dependent DAG generation but relies on baseline DAG levels. Overexpression of RasGRP1 constitutively increases the GTP-loading rate of Ras, establishing a high flux through the RasGTP/GDP cycle that is counterbalanced by RasGAP activity.\",\n      \"method\": \"Ras-GTP pull-down assays, multiple RasGTP/GDP flux assays, PLCγ inhibitor experiments, cytokine stimulation in T-ALL vs normal thymocytes\",\n      \"journal\": \"Science signaling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — three distinct Ras-GTP loading assays plus PLCγ independence experiments; single lab\",\n      \"pmids\": [\"23532335\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"RasGRP1 missense mutation in the EF-hand (Anaef allele) reduces Ras-ERK activation but causes elevated tonic mTOR-S6K signaling and CD44 overexpression on naïve T cells. The mTOR-dependent T cell dysregulation and autoantibody production in Rasgrp1Anaef mice are rescued by a reduction-of-function Mtor mutation, placing RasGRP1 upstream of mTOR in tonic T cell signaling.\",\n      \"method\": \"ENU mutagenesis, Rasgrp1Anaef knock-in mice, Rasgrp1Anaef x Mtorchino double-mutant mice, S6K phosphorylation assays, T cell subset analysis\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic epistasis with double-mutant rescue establishes pathway position; multiple orthogonal assays in a well-controlled mouse model\",\n      \"pmids\": [\"24336796\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"RasGRP1 creates a negative feedback loop that limits proliferative EGFR-SOS1-Ras signals in colorectal cancer cells. RasGRP1 and SOS1 act in functional opposition downstream of EGFR; genetic Rasgrp1 depletion in mice with activating KRas mutation or Apc mutation exacerbates Ras-ERK signaling and cell proliferation.\",\n      \"method\": \"Rasgrp1 conditional knockout in KrasG12D and Apc-mutant mice, EGFR stimulation assays, ERK phosphorylation, intestinal organoid proliferation assays\",\n      \"journal\": \"Nature cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — two independent genetic mouse models with consistent mechanistic outcomes; functional opposition with SOS1 demonstrated\",\n      \"pmids\": [\"26005835\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"RasGRP1 overexpression in T-ALL increases basal Ras GTP-loading flux and enables IL-2/7/9 cytokine receptor signals to activate the Ras-Akt pathway. In these leukemic cells, cytokine stimulation decreases RasGAP activity rather than increasing GEF activity, revealing that the balance between RasGRP1-driven GTP loading and RasGAP-driven hydrolysis determines net oncogenic Ras signaling.\",\n      \"method\": \"Ras-GTP pull-down, nucleotide exchange rate assays, Akt/ERK phosphorylation assays, cytokine stimulation with PLCγ inhibitor controls\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple mechanistic assays in T-ALL cells, single lab\",\n      \"pmids\": [\"26549032\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"RASGRP1 deficiency in humans causes combined immunodeficiency with impaired ERK phosphorylation in T and B cells, defective NK cell cytotoxicity with impaired granule convergence and actin accumulation, and decreased RhoA GTPase activation. Interaction proteomics identified DYNLL1 (dynein light chain) as a RasGRP1-interacting protein, linking RasGRP1 to cytoskeletal dynamics.\",\n      \"method\": \"Homozygosity mapping, exome sequencing, wild-type RASGRP1 rescue, interaction proteomics (Co-IP/MS), ERK phosphorylation assays, RhoA activation assay, NK cytotoxicity assay\",\n      \"journal\": \"Nature immunology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — human loss-of-function with WT rescue, interaction proteomics identifying DYNLL1, functional RhoA and cytoskeletal readouts\",\n      \"pmids\": [\"27776107\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"RasGRP1 is an HSP90 client protein. HDAC inhibitor-induced HSP90 acetylation causes release and proteasomal degradation of RasGRP1 (and CRAF), leading to MAPK pathway downregulation and BIM upregulation in lymphoma cells. RasGRP1 siRNA mimics the pro-apoptotic effects of HDAC inhibitors.\",\n      \"method\": \"Co-immunoprecipitation of HSP90-RasGRP1 complex, HDAC inhibitor treatment, siRNA knockdown of RasGRP1, Western blotting for protein stability, BIM/apoptosis assays in vivo and in vitro\",\n      \"journal\": \"Leukemia\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2/3 / Moderate — HSP90 client status confirmed by co-IP and degradation assay, functional consequences validated with siRNA, single lab\",\n      \"pmids\": [\"27890930\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"His212 in RasGRP1 functions as a pH sensor that alters the balance between inactive and active conformations. Structural comparison of autoinhibited RasGRP1 and active RasGRP4:H-Ras/RasGRP2:Rap1b complexes shows that the transition involves rearrangement of an interdomain linker at a fulcrum where His212 is located. Charge alteration at His212 via SNP variants alters signaling activity and plasma membrane recruitment.\",\n      \"method\": \"Crystal structure comparison, NMR analysis of pH-dependent conformational changes, functional assays of His212 SNP variants (plasma membrane recruitment, Ras signaling)\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — structural analysis (crystal structures + NMR) with functional validation of specific residue variants\",\n      \"pmids\": [\"28952923\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"SRSF1 (serine/arginine-rich splicing factor 1) directly binds exon 11 of RASGRP1 pre-mRNA and promotes inclusion of exon 11, maintaining wild-type RASGRP1 protein expression. Silencing SRSF1 in healthy T cells increases the ratio of alternatively spliced (exon-11-skipped) to wild-type RASGRP1 and decreases RASGRP1 protein; conversely, overexpression of SRSF1 in SLE T cells restores RASGRP1 protein and downstream DNMT1/IL-2 expression.\",\n      \"method\": \"Oligonucleotide-protein pulldown assay (direct binding), SRSF1 siRNA and overexpression, RT-PCR splicing analysis, Western blotting\",\n      \"journal\": \"Arthritis & rheumatology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct RNA-protein binding demonstrated, gain- and loss-of-function with splice isoform quantification, single lab\",\n      \"pmids\": [\"29905030\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"An intronic enhancer in RASGRP1 (containing SNP rs11631591) drives cell-type-specific RASGRP1 transcription in T lymphocytes. The risk allele of rs11631591 binds hnRNP-K, and inhibition of hnRNP-K in Jurkat and primary T cells downregulates RASGRP1 and ERK/MAPK signaling.\",\n      \"method\": \"Luciferase reporter assay (allele-specific enhancer activity), EMSA, mass spectrometry identification of hnRNP-K, ChIP-qPCR, hnRNP-K inhibition with functional readout\",\n      \"journal\": \"Frontiers in immunology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple biochemical methods validating enhancer and transcription factor, single lab\",\n      \"pmids\": [\"31164884\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"RUNX1 and its cofactor CBFB bind a RASGRP1 intrinsic enhancer and transcriptionally activate RASGRP1 expression. CRISPR-Cas9 disruption of this enhancer reduces RasGRP1 protein levels, and reduced RUNX1 expression in autoimmune patient CD4+ T cells correlates with decreased RASGRP1 levels.\",\n      \"method\": \"CRISPR-Cas9 enhancer disruption, ChIP-seq H3K27ac profiling, RUNX1/CBFB binding confirmation, RASGRP1 expression and ERK signaling assays\",\n      \"journal\": \"European journal of immunology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — CRISPR enhancer KO with functional expression readout, epigenetic data supporting mechanism, single lab\",\n      \"pmids\": [\"33065764\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"RasGRP1 promotes L-DOPA-induced dyskinesia (LID) in the striatum by activating ERK and mTOR signaling. RasGRP1 acts as a GEF for Rheb (the activator of mTOR kinase complex) in addition to its canonical Ras GEF activity. RasGRP1 knockout mice show dramatically reduced LID without impaired L-DOPA therapeutic effects.\",\n      \"method\": \"RasGRP1 knockout mice in parkinsonian model, L-DOPA dyskinesia behavioral assays, ERK and mTOR phosphorylation in striatum, tandem mass spectrometry proteomics for downstream targets\",\n      \"journal\": \"Science advances\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — knockout mouse with defined behavioral and biochemical phenotypes, novel Rheb GEF activity supported by proteomics but would benefit from direct reconstitution\",\n      \"pmids\": [\"32426479\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Phorbol ester stimulation of RasGRP1 in renal distal convoluted tubule cells activates the Ras-ERK pathway and suppresses the surface expression and function of the sodium-chloride cotransporter (NCC) via NCC ubiquitination and dynamin-dependent endocytosis. RasGRP1 gene silencing prevents phorbol ester-induced Ras activation, ERK activation, NCC ubiquitination, and endocytosis.\",\n      \"method\": \"RasGRP1 siRNA knockdown, biotinylation assay of surface NCC, internalization assay, dynamin dominant-negative construct, ubiquitin immunoprecipitation, radiotracer NCC activity assay\",\n      \"journal\": \"American journal of physiology. Renal physiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple assays establishing RasGRP1→ERK→ubiquitination→endocytosis mechanism, single lab\",\n      \"pmids\": [\"20392800\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Phorbol ester activates RasGRP1 in renal distal convoluted tubule cells, which in turn activates H-Ras and ERK1/2 MAPK in a PKC-independent manner, leading to suppression of NCC function and surface expression. RasGRP1 gene silencing prevents all of these effects, identifying RasGRP1 as the critical mediator of phorbol ester action on NCC.\",\n      \"method\": \"RasGRP1 siRNA knockdown, PKC/MAPK inhibitor experiments, 22Na+ radiotracer NCC activity assay, biotinylation of surface NCC, H-Ras activation assay\",\n      \"journal\": \"Proceedings of the National Academy of Sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — RNAi-based mechanism dissection with PKC independence shown and Ras isoform specificity established, single lab\",\n      \"pmids\": [\"18077438\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"RasGRP1 interacts with and stabilizes Rhes (Ras homolog enriched in striatum), increasing Rhes synaptic accumulation in the striatum. RasGRP1 affects the composition of the amphetamine-induced Rhes interactome (Rhesactome), including proteins associated with neuropsychiatric disorders. Partial depletion of RasGRP1 attenuates the enhanced locomotor response to amphetamine seen in Rhes-heterozygous mice.\",\n      \"method\": \"Rhes-heterozygous and RasGRP1 knockout mouse models, proteomic analysis of striatal Rhes-interactome, locomotor behavioral assays, western blot for Rhes synaptic localization\",\n      \"journal\": \"Science signaling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2/3 / Moderate — proteomics plus behavioral genetics establish RasGRP1-Rhes interaction and functional consequence, single lab\",\n      \"pmids\": [\"27902448\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"In B cells, RasGRP1 activates a proapoptotic pathway involving PKC/Ras-Raf-MEK-ERK signaling leading to phosphorylation of the BH3-only protein Bim by ERK on sites associated with increased apoptotic activity, followed by Bak-Bax complex formation and mitochondrial membrane permeabilization. This apoptosis can be suppressed by Bim downregulation or Bcl-2 overexpression.\",\n      \"method\": \"DAG analogue stimulation, in vitro ERK-Bim kinase assay, Bim siRNA, Bcl-2 overexpression, Bak-Bax co-immunoprecipitation, mitochondrial membrane potential assay\",\n      \"journal\": \"Experimental hematology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro kinase assay for ERK-Bim phosphorylation, multiple pathway inhibitors and genetic rescue experiments, single lab\",\n      \"pmids\": [\"19100522\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"SKAP55 co-immunoprecipitates with RasGRP1 via its C-terminus; this interaction is enhanced by tyrosine phosphorylation of SKAP55. Overexpression of SKAP55 disrupts TCR-to-Ras-ERK signaling, and this effect requires the RasGRP1-binding C-terminus of SKAP55; constitutively active Ras or Raf-1 overcome SKAP55 overexpression, placing the SKAP55-RasGRP1 interaction upstream of Ras.\",\n      \"method\": \"Co-immunoprecipitation, SKAP55 domain deletion constructs, TCR-induced ERK and AP-1 reporter assays, constitutively active Ras/Raf rescue\",\n      \"journal\": \"Molecular immunology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single co-IP with functional overexpression data, no reciprocal pull-down or in vitro reconstitution\",\n      \"pmids\": [\"17658605\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"RasGRP1 is a DAG- and calcium-regulated Ras guanine nucleotide exchange factor that is maintained in an autoinhibited state (crystal structure defined) and activated by DAG-driven membrane recruitment via its C1 domain and/or phosphoinositide binding by its PT domain; once membrane-localized, RasGRP1 catalyzes GDP-for-GTP exchange on Ras at the plasma membrane or Golgi apparatus, directly activates Ras and—by generating RasGTP that primes the allosteric pocket of SOS—creates a positive feedback loop for robust lymphocyte Ras-ERK signaling downstream of TCR/BCR-PLCγ-DAG; RasGRP1 activity is tuned by PKC-mediated phosphorylation of Thr184, alternative splicing of its EF-hand, pH-sensing by His212, and suppression by SKAP55 binding, while its expression is transcriptionally controlled by RUNX1/CBFB and post-transcriptionally by SRSF1-dependent splicing, and it additionally functions as a GEF for Rheb to activate mTOR in the striatum and interfaces with cytoskeletal dynamics through DYNLL1.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"RASGRP1 is a diacylglycerol (DAG)- and calcium-regulated guanine nucleotide exchange factor (GEF) that couples antigen-receptor and phospholipase-C signaling to Ras-ERK activation, and it is the essential, non-redundant link between TCR/DAG signaling and Ras during thymocyte maturation [#0, #3]. Its activation is governed by membrane recruitment: a high-affinity C1 domain binds DAG/phorbol esters and drives translocation to membranes, while a Plasma membrane Targeter (PT) domain binds PI3K-generated phosphoinositides, and these inputs are countered by a Suppressor-of-PT domain and modulated by an EF-hand whose alternative splicing tunes targeting [#1, #4, #13, #15]. In the resting state RASGRP1 is autoinhibited, with the Ras-binding site blocked by an interdomain linker and the membrane surface buried in a dimerization interface; calcium binding and a His212 pH-sensing fulcrum drive the conformational transition to the active form [#18, #25]. Once membrane-localized, RASGRP1 catalyzes nucleotide exchange on Ras at both the plasma membrane and the Golgi—a Golgi compartment specificity unique to the RasGRP family—and amplifies signaling by generating RasGTP that primes the allosteric pocket of SOS, establishing a positive feedback loop that explains its dominance in lymphocytes [#6, #7, #10]. Activity is further tuned by PKC-dependent Thr184 phosphorylation, DGKalpha-mediated DAG clearance, and negative regulation by the adaptor SKAP55, and expression is controlled transcriptionally by RUNX1/CBFB and an hnRNP-K-bound enhancer and post-transcriptionally by SRSF1-dependent exon-11 splicing [#5, #9, #12, #26, #27, #28]. Beyond canonical Ras signaling, RASGRP1 acts as a GEF for Rheb to activate mTOR in striatal neurons and interfaces with cytoskeletal dynamics via DYNLL1 [#20, #23, #29]. Human biallelic loss of RASGRP1 causes a combined immunodeficiency with impaired T/B cell ERK signaling and defective NK cytotoxicity [#23].\",\n  \"teleology\": [\n    {\n      \"year\": 1998,\n      \"claim\": \"Established RASGRP1 as a Ras GEF and identified DAG-driven membrane translocation through its C1 domain as the activation mechanism, defining the protein's core biochemical logic.\",\n      \"evidence\": \"NIH 3T3 transformation, subcellular fractionation, and domain-deletion/substitution mutagenesis with GEF and MAPK readouts\",\n      \"pmids\": [\"9582122\", \"9819387\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not resolve which Ras isoforms or compartments are engaged in physiological cells\", \"Activation mechanism studied in fibroblasts, not lymphocytes\"]\n    },\n    {\n      \"year\": 2000,\n      \"claim\": \"Demonstrated that RASGRP1 is the essential, non-redundant GEF linking TCR/PLC-gamma/DAG signaling to Ras and is required for mature thymocyte development, moving it from a transforming protein to a physiological immune signaling node.\",\n      \"evidence\": \"Antibody inhibition and overexpression in Jurkat cells plus a targeted knockout mouse with thymocyte phenotyping and Ras activation assays\",\n      \"pmids\": [\"10807788\", \"11017103\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not define the spatial site of Ras activation\", \"Mechanism of how DAG signal is converted to sustained Ras output unresolved\"]\n    },\n    {\n      \"year\": 2000,\n      \"claim\": \"Quantified the C1 domain as a high-affinity DAG/phorbol ester receptor distinct from PKC, establishing the ligand-binding basis of recruitment.\",\n      \"evidence\": \"Radioligand binding ([3H]PDBu) with competition and cofactor analysis\",\n      \"pmids\": [\"10779365\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"In vitro binding did not address membrane discrimination in cells\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Revealed compartmentalized Ras signaling: RASGRP1 activates Ras at the Golgi, a localization unique to the RasGRP family, with calcium positively regulating Golgi Ras while distinct GAPs negatively regulate plasma membrane Ras.\",\n      \"evidence\": \"Live-cell imaging of GFP-tagged RasGRP1 and Ras biosensors with compartment-resolved activation assays in Jurkat cells; systematic GEF comparison\",\n      \"pmids\": [\"12845332\", \"12782630\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How C1 versus other domains select internal versus plasma membrane was not fully resolved\", \"Functional consequence of Golgi versus PM Ras pools unclear\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Defined a DAG-PKC-RasGRP1-Ras-ERK feedback circuit by identifying Thr184 phosphorylation by novel PKC as a positive regulatory event.\",\n      \"evidence\": \"RasGRP1-deficient Jurkat clones, RNAi, phospho-specific antibodies, and PKC inhibitors\",\n      \"pmids\": [\"15899849\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Precise effect of Thr184 phosphorylation on conformation or localization not structurally defined\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Showed RASGRP1 amplifies Ras signaling by priming the SOS allosteric pocket with RasGTP, explaining its dominance in initiating lymphocyte Ras-ERK feedback.\",\n      \"evidence\": \"Genetic knockout/reconstitution in Jurkat and DT40 cells with allosteric SOS mutants and RasV12C40 substitution\",\n      \"pmids\": [\"17283063\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Quantitative kinetics of the RasGRP1-SOS handoff in vivo not established\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Dissected the membrane-targeting machinery, defining cooperative C1, PT, and SuPT domains and the C-terminal tail as determinants of receptor-induced localization.\",\n      \"evidence\": \"Domain deletion/mutational analysis with live imaging in B cells and fibroblasts, and tail-deleted knock-in mice\",\n      \"pmids\": [\"17567957\", \"22719950\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab studies\", \"Molecular partners mediating tail-dependent trafficking unidentified\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Established that EF1, independent of bulk calcium flux, and its alternative splicing modulate plasma membrane targeting by counteracting the SuPT domain, with the GEF Ras-binding site itself feeding back into localization.\",\n      \"evidence\": \"EF-hand mutagenesis, splice isoform expression, calcium chelation, and live imaging in B cells\",\n      \"pmids\": [\"19168098\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single lab\", \"Physiological splice ratios and their regulation not quantified here\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Connected PI3K signaling to RASGRP1 recruitment by demonstrating direct phosphoinositide binding by a basic/hydrophobic cluster in the PT domain.\",\n      \"evidence\": \"Lipid vesicle binding assays, PI3K inhibitors, cluster mutagenesis, and BCR ligation imaging\",\n      \"pmids\": [\"21285350\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single lab\", \"Relative contribution of PT/phosphoinositide versus C1/DAG in vivo not quantified\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Identified a calcium-driven, DAG-independent RASGRP1/PKC-delta proapoptotic ERK pathway required for negative selection of autoreactive B cells, distinguishing it biochemically from canonical DAG-driven ERK.\",\n      \"evidence\": \"PKC-delta knockout mice, STIM1 and RasGRP1 manipulation, and pathway-resolved ERK and apoptosis assays\",\n      \"pmids\": [\"21441934\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How calcium converts ERK output to proapoptotic rather than proliferative not fully mechanistic\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Provided the structural basis for autoinhibition and calcium-dependent activation, showing the Ras-binding site is blocked and the membrane surface buried in a dimerization interface that calcium disrupts.\",\n      \"evidence\": \"X-ray crystallography, NMR, and structure-guided mutagenesis\",\n      \"pmids\": [\"23908768\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Full-length protein with all regulatory domains not crystallized\", \"Membrane-bound active conformation not directly visualized\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Revealed an oncogenic mode in T-ALL where RASGRP1 overexpression raises basal Ras GTP-loading flux, enabling cytokine receptors to drive Ras independently of acute PLC-gamma/DAG.\",\n      \"evidence\": \"Multiple Ras-GTP flux assays and PLC-gamma inhibitor experiments in T-ALL versus normal thymocytes\",\n      \"pmids\": [\"23532335\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single lab\", \"Mechanism enabling DAG-independent activation at baseline DAG unclear\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Placed RASGRP1 upstream of mTOR in tonic T cell signaling using genetic epistasis, showing an EF-hand mutant uncouples reduced Ras-ERK from elevated mTOR-S6K activity and autoimmunity.\",\n      \"evidence\": \"ENU-derived Rasgrp1(Anaef) knock-in crossed to an Mtor reduction-of-function allele with S6K and T cell subset readouts\",\n      \"pmids\": [\"24336796\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct biochemical link from RASGRP1 to mTOR not defined in this study\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Defined a context-dependent negative-feedback role: in epithelial/colorectal cancer cells RASGRP1 opposes EGFR-SOS1-Ras signaling, contrasting with its amplifying role in lymphocytes.\",\n      \"evidence\": \"Rasgrp1 conditional knockout in KrasG12D and Apc-mutant mice with EGFR stimulation and organoid proliferation assays\",\n      \"pmids\": [\"26005835\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular basis of the RASGRP1-SOS1 opposition not structurally resolved\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Showed that net oncogenic Ras output in RASGRP1-overexpressing T-ALL is set by the balance between RASGRP1-driven GTP loading and RasGAP-driven hydrolysis, with cytokines acting by decreasing GAP activity.\",\n      \"evidence\": \"Ras-GTP pull-down, exchange-rate assays, and Akt/ERK readouts with PLC-gamma controls\",\n      \"pmids\": [\"26549032\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single lab\", \"Identity of the cytokine-regulated GAP not defined\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Identified human RASGRP1 loss-of-function as a cause of combined immunodeficiency and linked RASGRP1 to cytoskeletal/NK cell function via RhoA activation and a DYNLL1 interaction.\",\n      \"evidence\": \"Homozygosity mapping, exome sequencing, WT rescue, interaction proteomics, and RhoA/NK cytotoxicity assays\",\n      \"pmids\": [\"27776107\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How RASGRP1 controls RhoA and DYNLL1-dependent cytoskeletal events mechanistically unresolved\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Showed RASGRP1 stabilizes the striatal GTPase Rhes and shapes its interactome, extending RASGRP1 function into neuronal/behavioral regulation.\",\n      \"evidence\": \"Rhes-heterozygous and RasGRP1 knockout mice, striatal Rhes-interactome proteomics, and locomotor behavioral assays\",\n      \"pmids\": [\"27902448\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single lab\", \"Whether stabilization reflects direct GEF/binding activity not resolved\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Defined His212 as a pH-sensing fulcrum controlling the autoinhibited-to-active transition, with SNP variants altering signaling and membrane recruitment.\",\n      \"evidence\": \"Crystal structure comparison, NMR of pH-dependent changes, and functional assays of His212 variants\",\n      \"pmids\": [\"28952923\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological contexts where intracellular pH gates RASGRP1 not established\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Established post-transcriptional control of RASGRP1 by SRSF1, which binds exon 11 and promotes its inclusion to maintain wild-type protein, relevant to lupus T cell dysfunction.\",\n      \"evidence\": \"Oligonucleotide-protein pulldown, SRSF1 loss/gain of function, splicing RT-PCR, and Western blot in healthy and SLE T cells\",\n      \"pmids\": [\"29905030\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single lab\", \"Functional difference between exon-11-included and -skipped isoforms not biochemically defined\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Identified an intronic enhancer SNP whose risk allele binds hnRNP-K to drive T-cell-specific RASGRP1 transcription, linking genetic variation to ERK/MAPK signaling.\",\n      \"evidence\": \"Allele-specific luciferase, EMSA, mass spectrometry, ChIP-qPCR, and hnRNP-K inhibition with functional readouts\",\n      \"pmids\": [\"31164884\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single lab\", \"In vivo contribution of the enhancer to autoimmunity not tested\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Defined RUNX1/CBFB transcriptional activation of RASGRP1 via an intrinsic enhancer, connecting reduced RUNX1 to lowered RASGRP1 in autoimmune T cells.\",\n      \"evidence\": \"CRISPR-Cas9 enhancer disruption, H3K27ac ChIP-seq, RUNX1/CBFB binding confirmation, and expression/ERK assays\",\n      \"pmids\": [\"33065764\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single lab\", \"Interplay with the hnRNP-K enhancer not integrated\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Demonstrated a non-Ras catalytic function: RASGRP1 acts as a Rheb GEF to drive ERK/mTOR-dependent L-DOPA-induced dyskinesia in the striatum.\",\n      \"evidence\": \"RasGRP1 knockout in a parkinsonian model with dyskinesia behavior, striatal ERK/mTOR phosphorylation, and proteomics\",\n      \"pmids\": [\"32426479\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct reconstitution of Rheb GEF activity not performed\", \"Single lab\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Extended RASGRP1 signaling to renal epithelium, where it drives Ras-ERK-dependent ubiquitination and dynamin-dependent endocytosis of the NCC cotransporter.\",\n      \"evidence\": \"RasGRP1 siRNA, surface NCC biotinylation, internalization and ubiquitin assays, and dominant-negative dynamin in distal convoluted tubule cells\",\n      \"pmids\": [\"20392800\", \"18077438\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single lab\", \"Physiological trigger of RASGRP1 in renal tubule in vivo unclear\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How the multiple regulatory inputs (C1/DAG, PT/phosphoinositide, EF-hand/calcium, His212/pH, Thr184 phosphorylation) are integrated on a full-length, membrane-bound RASGRP1 to set compartment-specific Ras versus Rheb output remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No full-length membrane-bound active structure\", \"Quantitative integration of the regulatory inputs not modeled\", \"Direct biochemical demonstration of Rheb GEF activity outstanding\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005085\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [1, 13, 15]},\n      {\"term_id\": \"GO:0005794\", \"supporting_discovery_ids\": [6, 7, 8]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 6, 10]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [3, 17, 23]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"SOS1\", \"SKAP55\", \"DYNLL1\", \"Rhes\", \"ZAP-70\", \"GNAI2\", \"HSP90\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}