{"gene":"ARHGEF25","run_date":"2026-06-09T22:02:44","timeline":{"discoveries":[{"year":2007,"finding":"Crystal structure of the Gαq–p63RhoGEF–RhoA ternary complex revealed that Gαq engages p63RhoGEF via its effector-binding site and C-terminal region, and that this interaction relieves autoinhibition of the catalytic DH domain imposed by the adjacent PH domain, thereby activating RhoA.","method":"X-ray crystallography of ternary complex; functional validation in vitro and in intact cells","journal":"Science","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure of ternary complex with in vitro and cell-based functional validation in a single rigorous study","pmids":["18096806"],"is_preprint":false},{"year":2007,"finding":"Activated Gαq directly relieves autoinhibition of p63RhoGEF by interacting with a highly conserved C-terminal extension of the PH domain; basally, the DH domain is autoinhibited by the PH domain.","method":"Biochemical/biophysical assays with purified proteins; deletion and mutant analysis","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — reconstituted in vitro with purified components, multiple orthogonal methods, independently consistent with crystal structure paper","pmids":["17606614"],"is_preprint":false},{"year":2005,"finding":"Active Gαq or Gα11, but not Gα12 or Gα13, directly interacts with p63RhoGEF at its C-terminal half and strongly enhances p63RhoGEF-induced RhoA activation; this activation is independent of and competes with canonical phospholipase Cβ activation.","method":"Co-immunoprecipitation; Gq/11-coupled receptor stimulation (M3-cholinoceptor, H1 receptor); RhoA activation assays; dominant-negative Gα mutants","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP plus multiple receptor and mutant Gα conditions, replicated by structural study","pmids":["15632174"],"is_preprint":false},{"year":2002,"finding":"p63RhoGEF specifically catalyzes GDP/GTP exchange on RhoA (not Rac1 or Cdc42) in vitro; RhoA activation in intact cells requires the presence of the PH domain; p63RhoGEF is localized to the sarcomeric I-band (cardiac sarcomeric actin) in human heart.","method":"In vitro guanine nucleotide exchange assay; confocal immunocytochemistry; stress fiber formation assay in fibroblasts and cardiac myoblasts","journal":"Journal of cell science","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — in vitro exchange assay for substrate specificity plus cellular localization and functional readout, foundational study independently replicated","pmids":["11861769"],"is_preprint":false},{"year":2004,"finding":"p63RhoGEF and GEFT are isoforms encoded by the same gene; when expressed in cells both activate RhoA (not Rac1 or Cdc42) and induce SRF-mediated gene transcription in a C3-transferase-sensitive (Rho-dependent) manner, and both induce actin stress fibers.","method":"RT-PCR for isoform detection; RhoA/Rac1/Cdc42 activation assays; SRF reporter assay; C3 transferase inhibition; actin stress fiber morphology","journal":"Naunyn-Schmiedeberg's archives of pharmacology","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (GTPase assay, reporter, pharmacological inhibition), establishes gene identity and RhoA specificity of both isoforms","pmids":["15069594"],"is_preprint":false},{"year":2003,"finding":"GEFT (N-terminally truncated isoform of ARHGEF25) has exchange activity for Rac1 and Cdc42 in vitro and promotes foci formation, cell proliferation, migration, and actin cytoskeletal reorganization (filopodia, lamellipodia) upon overexpression in NIH3T3 cells.","method":"In vitro GTPase exchange assay; GST-PAK pull-down for GTP-bound Rac1/Cdc42; NIH3T3 focus formation; cell proliferation and migration assays","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vitro exchange assay plus multiple cellular readouts; note that Lutz 2004 showed full-length p63RhoGEF/GEFT activates RhoA not Rac1/Cdc42 in other cell contexts, so substrate specificity is context-dependent","pmids":["12547822"],"is_preprint":false},{"year":2004,"finding":"GEFT promotes neurite outgrowth in neuroblastoma cells via activation of Rac1, Cdc42, and RhoA; neurite outgrowth is primarily mediated by Rac1 and requires downstream effectors PAK1 and PAK5; GEFT also promotes dendritic spine enlargement in hippocampal neurons.","method":"GTP-bound GTPase pull-down; dominant-negative constructs; PAK1/PAK5 expression; Neuro2A cell neurite outgrowth assay; hippocampal neuron morphology","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — active GTPase pull-down plus dominant-negative pathway placement, single lab","pmids":["15322108"],"is_preprint":false},{"year":2005,"finding":"GEFT promotes myogenesis of C2C12 cells via activation of RhoA, Rac1, and Cdc42 and their downstream effectors; a dominant-negative GEFT mutant inhibits myogenesis; GEFT inhibits insulin-induced adipogenesis in 3T3L1 preadipocytes; endogenous GEFT protein levels are modulated during skeletal muscle regeneration in vivo.","method":"Gene transfer in cardiotoxin-injured mouse tibialis anterior; C2C12 differentiation assay; dominant-negative mutant; GTPase activation assays; 3T3L1 adipogenesis assay","journal":"Molecular and cellular biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo gene transfer plus cell-based loss- and gain-of-function with dominant-negative and GTPase assays, single lab","pmids":["16314529"],"is_preprint":false},{"year":2008,"finding":"Bves (an integral membrane protein) directly physically interacts with GEFT; Bves expression reduces Rac1 and Cdc42 (but not RhoA) activity, and alters cell locomotion speed and cell roundness, positioning Bves as a negative regulator of GEFT-mediated Rac1/Cdc42 signaling.","method":"Co-immunoprecipitation; colocalization in adult skeletal muscle; active Rac1/Cdc42/RhoA pull-down assays; cell morphology and migration assays","journal":"Proceedings of the National Academy of Sciences","confidence":"Medium","confidence_rationale":"Tier 2-3 / Moderate — Co-IP plus active GTPase pull-downs and functional cellular readouts, single lab","pmids":["18541910"],"is_preprint":false},{"year":2008,"finding":"MLK3 (a MAP3K) binds directly to p63RhoGEF/GEFT and thereby prevents Gαq from activating p63RhoGEF, limiting RhoA activation; this scaffolding function of MLK3 is independent of its kinase activity and is required for normal cell migration.","method":"Co-immunoprecipitation; kinase-dead MLK3 mutants; RhoA activation assays; cell migration assays","journal":"Molecular cell","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP with kinase-dead mutants and RhoA activation assays establishing mechanism, single lab","pmids":["18851832"],"is_preprint":false},{"year":2011,"finding":"p63RhoGEF is palmitoylated at N-terminal cysteines (Cys-23/25/26); this palmitoylation is required for plasma membrane localization and for full basal GEF activity in cells; mutation of these cysteines to serine relocates p63RhoGEF to the cytoplasm and reduces basal activity, which can be rescued by forced membrane targeting or co-expression with wild-type (but not palmitoylation-deficient) Gαq.","method":"Site-directed mutagenesis (Cys→Ser); subcellular fractionation; palmitoylation assay; RhoA activation assays; rapamycin-inducible membrane-recruitment rescue","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — mutagenesis with palmitoylation assay, localization and functional rescue experiments; multiple orthogonal methods in one study","pmids":["21832057"],"is_preprint":false},{"year":2011,"finding":"p63RhoGEF selectively couples Gαq/11 (but not Gα12/13) to RhoA activation in vascular smooth muscle; silencing endogenous p63RhoGEF in mouse portal vein preferentially reduces contractile force induced by the Gαq/11-coupled agonist endothelin-1 and phenylephrine over the Gα12/13-coupled agonist U46619; introduction of the isolated PH domain of p63RhoGEF into permeabilized rabbit portal vein inhibited Ca2+-sensitized force and RhoA activation.","method":"siRNA knockdown in mouse portal vein; ex vivo force measurements; permeabilized tissue PH-domain introduction; RhoA activation assays","journal":"Circulation research","confidence":"High","confidence_rationale":"Tier 2 / Strong — endogenous knockdown in intact tissue with functional force readout plus PH-domain dominant-negative experiment, replicated across two agonist systems","pmids":["21885830"],"is_preprint":false},{"year":2010,"finding":"In rat aortic smooth muscle cells, endogenous p63RhoGEF is the dominant mediator of fast angiotensin II–induced (Gq/11-dependent) RhoA activation; its knockdown abolished ANG II-induced stress fiber formation and cell elongation, reduced the mitogenic response, and impaired ANG II-driven contraction in a 3-D collagen model; p63RhoGEF did not activate Rac1 in this context.","method":"siRNA knockdown; RhoA/Rac1 activation assays; 2-D cell morphology; 3-D collagen contraction model; proliferation assay","journal":"FASEB journal","confidence":"High","confidence_rationale":"Tier 2 / Strong — endogenous loss-of-function with multiple orthogonal functional readouts (GTPase activity, morphology, contraction, proliferation)","pmids":["20739613"],"is_preprint":false},{"year":2009,"finding":"p63RhoGEF binds to constitutively active Gα16QL (a Gαq family member) via Co-IP; overexpressed p63RhoGEF competitively displaces PLCβ2 and TTC1 from Gα16QL, inhibiting IP3 production, Ras activation, STAT3 phosphorylation, and SRE transcriptional activation.","method":"Co-immunoprecipitation in HEK293 cells; IP3 production assay; STAT3 phosphorylation; SRE luciferase reporter; competition binding assays","journal":"Cellular signalling","confidence":"Medium","confidence_rationale":"Tier 2-3 / Moderate — Co-IP plus multiple downstream signaling readouts, single lab","pmids":["19332116"],"is_preprint":false},{"year":2013,"finding":"Pasteurella multocida toxin inhibits osteoblast differentiation via Gαq/11 activation of p63RhoGEF, which activates RhoA; activated RhoA then transactivates the MAP kinase cascade (Rho kinase → Ras → MEK → ERK), blocking osteoblast differentiation; p63RhoGEF does not interact with Gα12/13 or Gαi in this pathway.","method":"Primary osteoblast and ST-2 cell differentiation models; alkaline phosphatase assay; mineralization nodule formation; pharmacological inhibitors; siRNA; GTPase activation assays","journal":"PLoS pathogens","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — pathway placement via pharmacological inhibitors, siRNA knockdown, and multiple differentiation markers; single lab","pmids":["23696743"],"is_preprint":false},{"year":2013,"finding":"GPR116 (adhesion GPCR) promotes breast cancer cell migration, invasion, and lamellipodia/stress fiber formation through the Gαq–p63RhoGEF–RhoA/Rac1 pathway; GPR116 knockdown reduces RhoA and Rac1 activation, and p63RhoGEF knockdown phenocopies GPR116 knockdown.","method":"siRNA knockdown of GPR116 and p63RhoGEF; RhoA/Rac1 activation assays; cell migration and invasion assays; mouse mammary tumor metastasis models","journal":"Cancer research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — epistasis established by double knockdown plus GTPase activation and in vivo metastasis assays, single lab","pmids":["24008316"],"is_preprint":false},{"year":2014,"finding":"FRET-based live-cell imaging showed that Gαq and p63RhoGEF form a direct, dynamic complex upon GPCR activation; on/off kinetics of the Gαq–p63RhoGEF interaction closely match Gαq activity kinetics; RGS2 accelerates both Gαq deactivation and Gαq–p63RhoGEF complex dissociation; activation-dependent FRET between RGS2 and p63RhoGEF was detected, supporting a functional Gαq–p63RhoGEF–RGS2 complex.","method":"FRET (Gαq-CFP/Venus-p63RhoGEF) in single living cells; GPCR stimulation (H1, M3); RGS2 co-expression; downstream signaling assays","journal":"The Biochemical journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — FRET-based interaction kinetics in living cells with regulatory perturbation; single lab","pmids":["24299002"],"is_preprint":false},{"year":2016,"finding":"Three ARHGEF25 isoforms exist (p63RhoGEF580, GEFT, p63RhoGEF619); p63RhoGEF580 is constitutively plasma-membrane-localized while p63RhoGEF619 is cytosolic and translocates to the plasma membrane upon Gαq-coupled GPCR stimulation; both activate RhoA similarly after GPCR stimulation; synthetic membrane recruitment of p63RhoGEF619 increases RhoGEF activity but full activation requires allosteric activation by Gαq, revealing a dual role for Gαq (recruitment + allosteric activation) for cytosolic isoforms.","method":"Live-cell imaging; FRET; rapamycin-inducible membrane recruitment; FRAP (diffusion coefficients); RhoA activity FRET biosensor; GPCR stimulation","journal":"Scientific reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — live imaging with multiple quantitative methods; single lab but multiple orthogonal approaches","pmids":["27833100"],"is_preprint":false},{"year":2013,"finding":"p63RhoGEF (plasma membrane) signals more efficiently downstream of Gαq than GEFT (cytoplasmic); forced membrane recruitment of GEFT via rapamycin-inducible system restores efficient Gαq-mediated signaling; membrane localization increases effective concentration rather than encounter time.","method":"Live-cell imaging; FRET-based calcium signaling assay; rapamycin-dependent membrane recruitment; FRAP for diffusion coefficients","journal":"Scientific reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — quantitative live-cell imaging with inducible localization control; single lab","pmids":["23884432"],"is_preprint":false},{"year":2006,"finding":"GEFT protein is concentrated at actin-enriched regions in retinoic acid-induced primary neurites and at the growth cone tip in cAMP-induced axon-like extensions; GEFT promotes neurite outgrowth in both undifferentiated and differentiated Neuro2A cells.","method":"Immunofluorescence/confocal localization in differentiating Neuro2A cells; neurite outgrowth quantification with RA and dbcAMP treatment","journal":"Journal of neuroscience research","confidence":"Low","confidence_rationale":"Tier 3 / Weak — localization by immunofluorescence and overexpression phenotype, no pathway placement or mechanistic follow-up","pmids":["16496360"],"is_preprint":false},{"year":2011,"finding":"GEFT promotes lens fiber differentiation (cell elongation, lentoid formation, crystallin expression) in N/N1003A lens epithelial cells via a Rac1-dependent mechanism; Rac1 nuclear localization is required; pharmacological inhibition of Rac1 blocks GEFT-induced differentiation in ex vivo mouse lens explants.","method":"Transfection of lens epithelial cells; crystallin promoter luciferase assays; Rac1 inhibitor (NSC23766); ex vivo lens explant; immunohistochemistry","journal":"Current molecular medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — pharmacological and reporter-based pathway placement with ex vivo validation; single lab","pmids":["21663592"],"is_preprint":false},{"year":2015,"finding":"In cardiac fibroblasts, p63RhoGEF mediates angiotensin II-dependent RhoA activation, serum response factor activation, and CTGF expression/secretion; p63RhoGEF is localized to the trans-Golgi network in cardiac fibroblasts; its expression in engineered heart/connective tissue models increases tissue stiffness and contractile tension.","method":"siRNA knockdown; dominant-negative p63ΔN; RhoA activation assays; SRF reporter; CTGF ELISA; engineered heart muscle and connective tissue models; confocal colocalization","journal":"Journal of molecular and cellular cardiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — endogenous knockdown plus dominant-negative, multiple functional readouts in 2D and 3D models; single lab","pmids":["26392029"],"is_preprint":false},{"year":2019,"finding":"GEFT activates the Rac1/Cdc42-PAK1 signaling pathway to promote EMT (upregulation of N-cadherin, Snail, Slug, Twist, Zeb1, Zeb2; downregulation of E-cadherin) and thereby drives rhabdomyosarcoma invasion and metastasis; GEFT gene promoter hypomethylation is associated with elevated GEFT expression in RMS.","method":"RMS cell lines; BALB/c nude mouse xenografts; siRNA/overexpression; active Rac1/Cdc42 assays; EMT marker western blot; bisulfite sequencing for methylation","journal":"EBioMedicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — GTPase activation assays and downstream EMT markers with in vivo xenograft validation; single lab","pmids":["31761617"],"is_preprint":false},{"year":2021,"finding":"GEFT inhibits autophagy and apoptosis in rhabdomyosarcoma cells via Rac1/Cdc42 activation of mTOR; Rac1/Cdc42 inhibition reduces the anti-autophagy/anti-apoptosis effect of GEFT.","method":"GEFT overexpression/knockdown in RMS cells; Rac1/Cdc42 inhibitor; autophagy markers (Beclin1, LC3); apoptosis markers (Bcl-2, Bax); mTOR activity assays","journal":"Frontiers in oncology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — pharmacological inhibitor-based pathway placement without direct mechanistic demonstration; single lab","pmids":["34221974"],"is_preprint":false},{"year":2025,"finding":"GNAQ forms a complex with ARHGEF25 (Co-IP) and promotes RhoA activation in NK/T-cell lymphoma; GNAQ T96S mutation abolishes wild-type GNAQ ability to activate the GNAQ-ARHGEF25-RhoA pathway and trigger apoptosis.","method":"Co-immunoprecipitation; mRNA sequencing; Western blotting; RhoA pathway activity; CCK-8 and flow cytometry","journal":"Cancer biology & therapy","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single Co-IP plus indirect downstream assays; single study with limited mechanistic depth","pmids":["41362935"],"is_preprint":false},{"year":2012,"finding":"Conditional knockout of Geft in the second heart field (using Mef2c-Cre) results in mice that develop normally with no discernible cardiac phenotype, indicating Geft is dispensable for second heart field development.","method":"Conditional knockout mouse (loxP-flanked exons 5-17, Mef2c-Cre); cardiac morphology assessment","journal":"BMB reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean conditional KO with defined developmental readout; finding is a rigorous negative result","pmids":["22449701"],"is_preprint":false}],"current_model":"ARHGEF25 (p63RhoGEF/GEFT) is a Dbl-family RhoA guanine nucleotide exchange factor that is constitutively palmitoylated at N-terminal cysteines and localized to the plasma membrane; activated Gαq/11 directly binds the C-terminal extension of its PH domain (as revealed by the crystal structure of the Gαq–p63RhoGEF–RhoA ternary complex), relieving autoinhibition of the catalytic DH domain by the PH domain and thereby activating RhoA, which mediates downstream processes including vascular smooth muscle Ca²⁺ sensitization and contraction, actin stress fiber formation, and cardiac fibroblast remodeling; MLK3 acts as a scaffold that binds p63RhoGEF and limits Gαq-mediated RhoA activation, while RGS2 accelerates Gαq–p63RhoGEF dissociation; a longer cytosolic isoform (p63RhoGEF619) requires both membrane recruitment and allosteric activation by Gαq for full activity."},"narrative":{"mechanistic_narrative":"ARHGEF25 (p63RhoGEF/GEFT) is a Dbl-family guanine nucleotide exchange factor that couples Gαq/11-linked GPCR signaling to Rho-family GTPase activation, controlling actin cytoskeletal remodeling, smooth muscle contraction, and tissue differentiation [PMID:18096806, PMID:11861769, PMID:21885830]. The full-length p63RhoGEF catalyzes GDP/GTP exchange selectively on RhoA in vitro, an activity that requires its PH domain and drives actin stress fiber formation and SRF-mediated transcription [PMID:11861769, PMID:15069594]. Activation is governed by an autoinhibitory arrangement in which the PH domain restrains the catalytic DH domain; active Gαq/11 (but not Gα12/13) directly engages a conserved C-terminal extension of the PH domain, relieving this autoinhibition and activating RhoA, as defined by the Gαq–p63RhoGEF–RhoA ternary crystal structure and reconstituted biochemistry [PMID:18096806, PMID:17606614, PMID:15632174]. N-terminal palmitoylation (Cys-23/25/26) targets the protein to the plasma membrane and is required for full basal activity, while a longer cytosolic isoform (p63RhoGEF619) requires both Gαq-driven membrane recruitment and allosteric activation for full activity [PMID:21832057, PMID:27833100]. Endogenous p63RhoGEF is the dominant mediator of Gαq/11-coupled agonist (angiotensin II, endothelin-1, phenylephrine)-induced RhoA activation, Ca²⁺-sensitized contractile force, stress fiber formation, and cardiac fibroblast CTGF expression and tissue stiffening [PMID:21885830, PMID:20739613, PMID:26392029]. The pathway is regulated by MLK3, which binds p63RhoGEF and limits Gαq-mediated RhoA activation independent of its kinase activity, and by RGS2, which accelerates Gαq–p63RhoGEF complex dissociation [PMID:18851832, PMID:24299002]. The N-terminally truncated GEFT isoform additionally exchanges on Rac1 and Cdc42 in vitro and promotes neurite outgrowth, myogenesis, lens fiber differentiation, and—through Rac1/Cdc42–PAK1 signaling—epithelial–mesenchymal transition in rhabdomyosarcoma, indicating context-dependent substrate usage [PMID:12547822, PMID:15322108, PMID:21663592, PMID:31761617].","teleology":[{"year":2002,"claim":"Established the core enzymatic identity: that p63RhoGEF is a RhoA-specific exchange factor requiring its PH domain, answering what GTPase it acts on and where it functions.","evidence":"In vitro nucleotide exchange assay, confocal localization, and stress fiber assay in fibroblasts/cardiac myoblasts","pmids":["11861769"],"confidence":"High","gaps":["Did not identify the upstream activating signal","Mechanism of PH-domain requirement unresolved"]},{"year":2003,"claim":"Showed that the N-terminally truncated GEFT isoform has exchange activity for Rac1 and Cdc42, introducing the question of isoform-dependent substrate specificity.","evidence":"In vitro exchange assay, GST-PAK pull-down, and NIH3T3 focus/migration assays","pmids":["12547822"],"confidence":"Medium","gaps":["Substrate specificity conflicts with RhoA-selective full-length data","Overexpression-based readouts"]},{"year":2004,"claim":"Resolved that p63RhoGEF and GEFT are isoforms of one gene and that both activate RhoA and SRF transcription in cells, unifying the gene identity.","evidence":"RT-PCR isoform detection, GTPase activation assays, SRF reporter, and C3 transferase inhibition","pmids":["15069594","15322108"],"confidence":"High","gaps":["Context-dependence of Rac1/Cdc42 versus RhoA usage not fully reconciled"]},{"year":2005,"claim":"Identified the upstream activator: active Gαq/11, but not Gα12/13, directly binds p63RhoGEF and enhances RhoA activation, placing it in Gq-coupled GPCR signaling.","evidence":"Co-IP, Gq/11-coupled receptor stimulation, RhoA assays, and dominant-negative Gα mutants; plus C2C12/3T3L1 differentiation models for GEFT","pmids":["15632174","16314529"],"confidence":"High","gaps":["Structural basis of Gαq binding not yet defined","Mechanism of autoinhibition relief unknown"]},{"year":2007,"claim":"Defined the activation mechanism at atomic resolution: Gαq engages the PH-domain C-terminal extension to relieve DH-domain autoinhibition, explaining how GPCR signals are transduced to RhoA.","evidence":"X-ray crystallography of the Gαq–p63RhoGEF–RhoA ternary complex and reconstituted biochemistry with purified proteins","pmids":["18096806","17606614"],"confidence":"High","gaps":["Did not address membrane targeting requirements","Dynamics in living cells unresolved"]},{"year":2008,"claim":"Identified negative regulators: MLK3 scaffolds and limits Gαq-driven activation, and Bves dampens GEFT-mediated Rac1/Cdc42 signaling, revealing regulatory inputs beyond Gαq.","evidence":"Co-IP, kinase-dead MLK3 mutants, active GTPase pull-downs, and migration assays","pmids":["18851832","18541910"],"confidence":"Medium","gaps":["Single-lab Co-IP for each interaction","Stoichiometry and competition with Gαq not quantified"]},{"year":2011,"claim":"Established that palmitoylation-driven plasma membrane localization is required for activity, and demonstrated the endogenous physiological role in vascular smooth muscle Ca²⁺ sensitization.","evidence":"Cys→Ser mutagenesis with palmitoylation/fractionation assays plus siRNA knockdown in portal vein with ex vivo force measurements","pmids":["21832057","21885830","20739613","21663592"],"confidence":"High","gaps":["Palmitoyl acyltransferase responsible not identified","Tissue specificity of contractile coupling incomplete"]},{"year":2014,"claim":"Captured the activation dynamics in living cells and the role of RGS2, showing Gαq–p63RhoGEF complex kinetics track Gαq activity and RGS2 accelerates dissociation.","evidence":"FRET imaging in single living cells with GPCR stimulation and RGS2 co-expression; plus pathological pathway placement in osteoblast and breast cancer models","pmids":["24299002","23696743","24008316","23884432"],"confidence":"Medium","gaps":["FRET interactions are single-lab","Quantitative contribution of RGS2 in vivo unknown"]},{"year":2016,"claim":"Distinguished isoform behavior, showing the cytosolic p63RhoGEF619 requires dual Gαq input (recruitment plus allosteric activation) whereas membrane-anchored p63RhoGEF580 is constitutively localized.","evidence":"Live-cell imaging, FRET, rapamycin-inducible recruitment, FRAP, and RhoA biosensors","pmids":["27833100"],"confidence":"Medium","gaps":["Physiological role of distinct isoforms in tissues not established"]},{"year":2025,"claim":"Extended the Gαq–ARHGEF25–RhoA axis to disease, linking a GNAQ mutation to loss of pathway activation and apoptosis in NK/T-cell lymphoma.","evidence":"Co-IP, RhoA pathway assays, and apoptosis readouts in lymphoma cells; plus EMT/autophagy roles in rhabdomyosarcoma","pmids":["41362935","31761617","34221974"],"confidence":"Low","gaps":["Single Co-IP without reciprocal validation","Mechanism of mutation-dependent loss not structurally resolved"]},{"year":null,"claim":"How the conflicting RhoA versus Rac1/Cdc42 substrate selectivity of full-length and truncated isoforms is determined in physiological contexts, and what endogenous loss-of-function reveals beyond the second heart field, remain unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No in vivo whole-organism phenotype beyond a dispensable second-heart-field knockout (22449701)","Structural basis of isoform-specific substrate switching unknown","Endogenous determinants of Rac1/Cdc42 versus RhoA usage uncharacterized"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[3,5,9]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[3,0,1]},{"term_id":"GO:0060089","term_label":"molecular transducer activity","supporting_discovery_ids":[0,2,11]}],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[10,17,11]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[10,17,18]},{"term_id":"GO:0005794","term_label":"Golgi apparatus","supporting_discovery_ids":[21]},{"term_id":"GO:0005856","term_label":"cytoskeleton","supporting_discovery_ids":[3,19]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0,2,11]},{"term_id":"R-HSA-397014","term_label":"Muscle contraction","supporting_discovery_ids":[11,12]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[6,7,20]}],"complexes":["Gαq–p63RhoGEF–RhoA ternary complex"],"partners":["GNAQ","GNA11","RHOA","MLK3","RGS2","BVES","GPR116"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q86VW2","full_name":"Rho guanine nucleotide exchange factor 25","aliases":["Guanine nucleotide exchange factor GEFT","Rac/Cdc42/Rho exchange factor GEFT","RhoA/Rac/Cdc42 guanine nucleotide exchange factor GEFT","p63RhoGEF"],"length_aa":580,"mass_kda":63.8,"function":"May play a role in actin cytoskeleton reorganization in different tissues since its activation induces formation of actin stress fibers. It works as a guanine nucleotide exchange factor for Rho family of small GTPases. Links specifically G alpha q/11-coupled receptors to RHOA activation. May be an important regulator of processes involved in axon and dendrite formation. In neurons seems to be an exchange factor primarily for RAC1. Involved in skeletal myogenesis (By similarity)","subcellular_location":"Cell membrane; Cytoplasm, myofibril, sarcomere","url":"https://www.uniprot.org/uniprotkb/Q86VW2/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/ARHGEF25","classification":"Not Classified","n_dependent_lines":19,"n_total_lines":1208,"dependency_fraction":0.015728476821192054},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/ARHGEF25","total_profiled":1310},"omim":[{"mim_id":"610215","title":"RHO GUANINE NUCLEOTIDE EXCHANGE FACTOR 25; ARHGEF25","url":"https://www.omim.org/entry/610215"},{"mim_id":"604577","title":"POPEYE DOMAIN cAMP EFFECTOR 1; POPDC1","url":"https://www.omim.org/entry/604577"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in many","driving_tissues":[],"url":"https://www.proteinatlas.org/search/ARHGEF25"},"hgnc":{"alias_symbol":["GEFT","p63RhoGEF"],"prev_symbol":[]},"alphafold":{"accession":"Q86VW2","domains":[{"cath_id":"1.20.900.10","chopping":"151-341","consensus_level":"high","plddt":93.9014,"start":151,"end":341},{"cath_id":"2.30.29.30","chopping":"347-396_405-488","consensus_level":"high","plddt":86.5633,"start":347,"end":488}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q86VW2","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q86VW2-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q86VW2-F1-predicted_aligned_error_v6.png","plddt_mean":67.69},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=ARHGEF25","jax_strain_url":"https://www.jax.org/strain/search?query=ARHGEF25"},"sequence":{"accession":"Q86VW2","fasta_url":"https://rest.uniprot.org/uniprotkb/Q86VW2.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q86VW2/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q86VW2"}},"corpus_meta":[{"pmid":"18096806","id":"PMC_18096806","title":"Structure of Galphaq-p63RhoGEF-RhoA complex reveals a pathway for the activation of RhoA by GPCRs.","date":"2007","source":"Science (New York, N.Y.)","url":"https://pubmed.ncbi.nlm.nih.gov/18096806","citation_count":181,"is_preprint":false},{"pmid":"15632174","id":"PMC_15632174","title":"The guanine nucleotide exchange factor p63RhoGEF, a specific link between Gq/11-coupled receptor signaling and RhoA.","date":"2005","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/15632174","citation_count":164,"is_preprint":false},{"pmid":"17606614","id":"PMC_17606614","title":"Galphaq directly activates p63RhoGEF and Trio via a conserved extension of the Dbl homology-associated pleckstrin homology domain.","date":"2007","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/17606614","citation_count":118,"is_preprint":false},{"pmid":"24008316","id":"PMC_24008316","title":"GPR116, an adhesion G-protein-coupled receptor, promotes breast cancer metastasis via the Gαq-p63RhoGEF-Rho GTPase pathway.","date":"2013","source":"Cancer research","url":"https://pubmed.ncbi.nlm.nih.gov/24008316","citation_count":95,"is_preprint":false},{"pmid":"12547822","id":"PMC_12547822","title":"A Rac/Cdc42-specific exchange factor, GEFT, induces cell proliferation, transformation, and migration.","date":"2003","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/12547822","citation_count":71,"is_preprint":false},{"pmid":"15322108","id":"PMC_15322108","title":"GEFT, a Rho family guanine nucleotide exchange factor, regulates neurite outgrowth and dendritic spine formation.","date":"2004","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/15322108","citation_count":70,"is_preprint":false},{"pmid":"16314529","id":"PMC_16314529","title":"Modulation of muscle regeneration, myogenesis, and adipogenesis by the Rho family guanine nucleotide exchange factor GEFT.","date":"2005","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/16314529","citation_count":69,"is_preprint":false},{"pmid":"21885830","id":"PMC_21885830","title":"p63RhoGEF couples Gα(q/11)-mediated signaling to Ca2+ sensitization of vascular smooth muscle contractility.","date":"2011","source":"Circulation research","url":"https://pubmed.ncbi.nlm.nih.gov/21885830","citation_count":60,"is_preprint":false},{"pmid":"18541910","id":"PMC_18541910","title":"Bves directly interacts with GEFT, and controls cell shape and movement through regulation of Rac1/Cdc42 activity.","date":"2008","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/18541910","citation_count":57,"is_preprint":false},{"pmid":"24356540","id":"PMC_24356540","title":"Increased level of p63RhoGEF and RhoA/Rho kinase activity in hypertensive patients.","date":"2014","source":"Journal of hypertension","url":"https://pubmed.ncbi.nlm.nih.gov/24356540","citation_count":54,"is_preprint":false},{"pmid":"11861769","id":"PMC_11861769","title":"Human p63RhoGEF, a novel RhoA-specific guanine nucleotide exchange factor, is localized in cardiac sarcomere.","date":"2002","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/11861769","citation_count":52,"is_preprint":false},{"pmid":"20739613","id":"PMC_20739613","title":"p63RhoGEF--a key mediator of angiotensin II-dependent signaling and processes in vascular smooth muscle cells.","date":"2010","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/20739613","citation_count":52,"is_preprint":false},{"pmid":"15069594","id":"PMC_15069594","title":"p63RhoGEF and GEFT are Rho-specific guanine nucleotide exchange factors encoded by the same gene.","date":"2004","source":"Naunyn-Schmiedeberg's archives of pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/15069594","citation_count":43,"is_preprint":false},{"pmid":"18851832","id":"PMC_18851832","title":"MLK3 limits activated Galphaq signaling to Rho by binding to p63RhoGEF.","date":"2008","source":"Molecular cell","url":"https://pubmed.ncbi.nlm.nih.gov/18851832","citation_count":40,"is_preprint":false},{"pmid":"22902181","id":"PMC_22902181","title":"p63RhoGEF: a new switch for G(q)-mediated activation of smooth muscle.","date":"2012","source":"Trends in cardiovascular medicine","url":"https://pubmed.ncbi.nlm.nih.gov/22902181","citation_count":33,"is_preprint":false},{"pmid":"31761617","id":"PMC_31761617","title":"Epigenetically upregulated GEFT-derived invasion and metastasis of rhabdomyosarcoma via epithelial mesenchymal transition promoted by the Rac1/Cdc42-PAK signalling pathway.","date":"2019","source":"EBioMedicine","url":"https://pubmed.ncbi.nlm.nih.gov/31761617","citation_count":31,"is_preprint":false},{"pmid":"23696743","id":"PMC_23696743","title":"Pasteurella multocida toxin prevents osteoblast differentiation by transactivation of the MAP-kinase cascade via the Gα(q/11)--p63RhoGEF--RhoA axis.","date":"2013","source":"PLoS pathogens","url":"https://pubmed.ncbi.nlm.nih.gov/23696743","citation_count":25,"is_preprint":false},{"pmid":"16496360","id":"PMC_16496360","title":"The Rho-family guanine nucleotide exchange factor GEFT enhances retinoic acid- and cAMP-induced neurite outgrowth.","date":"2006","source":"Journal of neuroscience research","url":"https://pubmed.ncbi.nlm.nih.gov/16496360","citation_count":21,"is_preprint":false},{"pmid":"27833100","id":"PMC_27833100","title":"Kinetics of recruitment and allosteric activation of ARHGEF25 isoforms by the heterotrimeric G-protein Gαq.","date":"2016","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/27833100","citation_count":19,"is_preprint":false},{"pmid":"21832057","id":"PMC_21832057","title":"Plasma membrane association of p63 Rho guanine nucleotide exchange factor (p63RhoGEF) is mediated by palmitoylation and is required for basal activity in cells.","date":"2011","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/21832057","citation_count":18,"is_preprint":false},{"pmid":"26392029","id":"PMC_26392029","title":"p63RhoGEF regulates auto- and paracrine signaling in cardiac fibroblasts.","date":"2015","source":"Journal of molecular and cellular cardiology","url":"https://pubmed.ncbi.nlm.nih.gov/26392029","citation_count":15,"is_preprint":false},{"pmid":"32269740","id":"PMC_32269740","title":"MicroRNA-29 family inhibits rhabdomyosarcoma formation and progression by regulating GEFT function.","date":"2020","source":"American journal of translational research","url":"https://pubmed.ncbi.nlm.nih.gov/32269740","citation_count":15,"is_preprint":false},{"pmid":"19332116","id":"PMC_19332116","title":"The RhoA-specific guanine nucleotide exchange factor p63RhoGEF binds to activated Galpha(16) and inhibits the canonical phospholipase Cbeta pathway.","date":"2009","source":"Cellular signalling","url":"https://pubmed.ncbi.nlm.nih.gov/19332116","citation_count":13,"is_preprint":false},{"pmid":"34221974","id":"PMC_34221974","title":"GEFT Inhibits Autophagy and Apoptosis in Rhabdomyosarcoma via Activation of the Rac1/Cdc42-mTOR Signaling Pathway.","date":"2021","source":"Frontiers in oncology","url":"https://pubmed.ncbi.nlm.nih.gov/34221974","citation_count":12,"is_preprint":false},{"pmid":"31105995","id":"PMC_31105995","title":"MicroRNA-874 functions as a tumor suppressor in rhabdomyosarcoma by directly targeting GEFT.","date":"2019","source":"American journal of cancer research","url":"https://pubmed.ncbi.nlm.nih.gov/31105995","citation_count":12,"is_preprint":false},{"pmid":"23884432","id":"PMC_23884432","title":"Signaling efficiency of Gαq through its effectors p63RhoGEF and GEFT depends on their subcellular location.","date":"2013","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/23884432","citation_count":11,"is_preprint":false},{"pmid":"21663592","id":"PMC_21663592","title":"GEFT, A Rho family guanine nucleotide exchange factor, regulates lens differentiation through a Rac1-mediated mechanism.","date":"2011","source":"Current molecular medicine","url":"https://pubmed.ncbi.nlm.nih.gov/21663592","citation_count":11,"is_preprint":false},{"pmid":"24299002","id":"PMC_24299002","title":"Dynamics of Gαq-protein-p63RhoGEF interaction and its regulation by RGS2.","date":"2014","source":"The Biochemical journal","url":"https://pubmed.ncbi.nlm.nih.gov/24299002","citation_count":10,"is_preprint":false},{"pmid":"28840514","id":"PMC_28840514","title":"Gαq/p63RhoGEF interaction in RhoA/Rho kinase signaling: investigation in Gitelman's syndrome and implications with hypertension.","date":"2017","source":"Journal of endocrinological investigation","url":"https://pubmed.ncbi.nlm.nih.gov/28840514","citation_count":4,"is_preprint":false},{"pmid":"38225540","id":"PMC_38225540","title":"Lnc-PSMA8-1 activated by GEFT promotes rhabdomyosarcoma progression via upregulation of mTOR expression by sponging miR-144-3p.","date":"2024","source":"BMC cancer","url":"https://pubmed.ncbi.nlm.nih.gov/38225540","citation_count":4,"is_preprint":false},{"pmid":"35116743","id":"PMC_35116743","title":"GEFT aberrant expression in soft tissue sarcomas.","date":"2019","source":"Translational cancer research","url":"https://pubmed.ncbi.nlm.nih.gov/35116743","citation_count":2,"is_preprint":false},{"pmid":"39616223","id":"PMC_39616223","title":"GEFT inhibits the GSDM-mediated proptosis signalling pathway, promoting the progression and drug resistance of rhabdomyosarcoma.","date":"2024","source":"Cell death & disease","url":"https://pubmed.ncbi.nlm.nih.gov/39616223","citation_count":1,"is_preprint":false},{"pmid":"22449701","id":"PMC_22449701","title":"Geft is dispensable for the development of the second heart field.","date":"2012","source":"BMB reports","url":"https://pubmed.ncbi.nlm.nih.gov/22449701","citation_count":1,"is_preprint":false},{"pmid":"41362935","id":"PMC_41362935","title":"GNAQ inhibits tumorigenesis via the ARHGEF25-mediated RHOA pathway in NK/T-cell lymphoma.","date":"2025","source":"Cancer biology & therapy","url":"https://pubmed.ncbi.nlm.nih.gov/41362935","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":19138,"output_tokens":6658,"usd":0.078642,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":15634,"output_tokens":3841,"usd":0.087097,"stage2_stop_reason":"end_turn"},"total_usd":0.165739,"stage1_batch_id":"msgbatch_0179Z2pxRYBsXi2xADneafRw","stage2_batch_id":"msgbatch_01LaY9ZaVdgjWArcZo9eqQE5","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2007,\n      \"finding\": \"Crystal structure of the Gαq–p63RhoGEF–RhoA ternary complex revealed that Gαq engages p63RhoGEF via its effector-binding site and C-terminal region, and that this interaction relieves autoinhibition of the catalytic DH domain imposed by the adjacent PH domain, thereby activating RhoA.\",\n      \"method\": \"X-ray crystallography of ternary complex; functional validation in vitro and in intact cells\",\n      \"journal\": \"Science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure of ternary complex with in vitro and cell-based functional validation in a single rigorous study\",\n      \"pmids\": [\"18096806\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Activated Gαq directly relieves autoinhibition of p63RhoGEF by interacting with a highly conserved C-terminal extension of the PH domain; basally, the DH domain is autoinhibited by the PH domain.\",\n      \"method\": \"Biochemical/biophysical assays with purified proteins; deletion and mutant analysis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — reconstituted in vitro with purified components, multiple orthogonal methods, independently consistent with crystal structure paper\",\n      \"pmids\": [\"17606614\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Active Gαq or Gα11, but not Gα12 or Gα13, directly interacts with p63RhoGEF at its C-terminal half and strongly enhances p63RhoGEF-induced RhoA activation; this activation is independent of and competes with canonical phospholipase Cβ activation.\",\n      \"method\": \"Co-immunoprecipitation; Gq/11-coupled receptor stimulation (M3-cholinoceptor, H1 receptor); RhoA activation assays; dominant-negative Gα mutants\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP plus multiple receptor and mutant Gα conditions, replicated by structural study\",\n      \"pmids\": [\"15632174\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"p63RhoGEF specifically catalyzes GDP/GTP exchange on RhoA (not Rac1 or Cdc42) in vitro; RhoA activation in intact cells requires the presence of the PH domain; p63RhoGEF is localized to the sarcomeric I-band (cardiac sarcomeric actin) in human heart.\",\n      \"method\": \"In vitro guanine nucleotide exchange assay; confocal immunocytochemistry; stress fiber formation assay in fibroblasts and cardiac myoblasts\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — in vitro exchange assay for substrate specificity plus cellular localization and functional readout, foundational study independently replicated\",\n      \"pmids\": [\"11861769\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"p63RhoGEF and GEFT are isoforms encoded by the same gene; when expressed in cells both activate RhoA (not Rac1 or Cdc42) and induce SRF-mediated gene transcription in a C3-transferase-sensitive (Rho-dependent) manner, and both induce actin stress fibers.\",\n      \"method\": \"RT-PCR for isoform detection; RhoA/Rac1/Cdc42 activation assays; SRF reporter assay; C3 transferase inhibition; actin stress fiber morphology\",\n      \"journal\": \"Naunyn-Schmiedeberg's archives of pharmacology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (GTPase assay, reporter, pharmacological inhibition), establishes gene identity and RhoA specificity of both isoforms\",\n      \"pmids\": [\"15069594\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"GEFT (N-terminally truncated isoform of ARHGEF25) has exchange activity for Rac1 and Cdc42 in vitro and promotes foci formation, cell proliferation, migration, and actin cytoskeletal reorganization (filopodia, lamellipodia) upon overexpression in NIH3T3 cells.\",\n      \"method\": \"In vitro GTPase exchange assay; GST-PAK pull-down for GTP-bound Rac1/Cdc42; NIH3T3 focus formation; cell proliferation and migration assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro exchange assay plus multiple cellular readouts; note that Lutz 2004 showed full-length p63RhoGEF/GEFT activates RhoA not Rac1/Cdc42 in other cell contexts, so substrate specificity is context-dependent\",\n      \"pmids\": [\"12547822\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"GEFT promotes neurite outgrowth in neuroblastoma cells via activation of Rac1, Cdc42, and RhoA; neurite outgrowth is primarily mediated by Rac1 and requires downstream effectors PAK1 and PAK5; GEFT also promotes dendritic spine enlargement in hippocampal neurons.\",\n      \"method\": \"GTP-bound GTPase pull-down; dominant-negative constructs; PAK1/PAK5 expression; Neuro2A cell neurite outgrowth assay; hippocampal neuron morphology\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — active GTPase pull-down plus dominant-negative pathway placement, single lab\",\n      \"pmids\": [\"15322108\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"GEFT promotes myogenesis of C2C12 cells via activation of RhoA, Rac1, and Cdc42 and their downstream effectors; a dominant-negative GEFT mutant inhibits myogenesis; GEFT inhibits insulin-induced adipogenesis in 3T3L1 preadipocytes; endogenous GEFT protein levels are modulated during skeletal muscle regeneration in vivo.\",\n      \"method\": \"Gene transfer in cardiotoxin-injured mouse tibialis anterior; C2C12 differentiation assay; dominant-negative mutant; GTPase activation assays; 3T3L1 adipogenesis assay\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo gene transfer plus cell-based loss- and gain-of-function with dominant-negative and GTPase assays, single lab\",\n      \"pmids\": [\"16314529\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Bves (an integral membrane protein) directly physically interacts with GEFT; Bves expression reduces Rac1 and Cdc42 (but not RhoA) activity, and alters cell locomotion speed and cell roundness, positioning Bves as a negative regulator of GEFT-mediated Rac1/Cdc42 signaling.\",\n      \"method\": \"Co-immunoprecipitation; colocalization in adult skeletal muscle; active Rac1/Cdc42/RhoA pull-down assays; cell morphology and migration assays\",\n      \"journal\": \"Proceedings of the National Academy of Sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 / Moderate — Co-IP plus active GTPase pull-downs and functional cellular readouts, single lab\",\n      \"pmids\": [\"18541910\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"MLK3 (a MAP3K) binds directly to p63RhoGEF/GEFT and thereby prevents Gαq from activating p63RhoGEF, limiting RhoA activation; this scaffolding function of MLK3 is independent of its kinase activity and is required for normal cell migration.\",\n      \"method\": \"Co-immunoprecipitation; kinase-dead MLK3 mutants; RhoA activation assays; cell migration assays\",\n      \"journal\": \"Molecular cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP with kinase-dead mutants and RhoA activation assays establishing mechanism, single lab\",\n      \"pmids\": [\"18851832\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"p63RhoGEF is palmitoylated at N-terminal cysteines (Cys-23/25/26); this palmitoylation is required for plasma membrane localization and for full basal GEF activity in cells; mutation of these cysteines to serine relocates p63RhoGEF to the cytoplasm and reduces basal activity, which can be rescued by forced membrane targeting or co-expression with wild-type (but not palmitoylation-deficient) Gαq.\",\n      \"method\": \"Site-directed mutagenesis (Cys→Ser); subcellular fractionation; palmitoylation assay; RhoA activation assays; rapamycin-inducible membrane-recruitment rescue\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — mutagenesis with palmitoylation assay, localization and functional rescue experiments; multiple orthogonal methods in one study\",\n      \"pmids\": [\"21832057\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"p63RhoGEF selectively couples Gαq/11 (but not Gα12/13) to RhoA activation in vascular smooth muscle; silencing endogenous p63RhoGEF in mouse portal vein preferentially reduces contractile force induced by the Gαq/11-coupled agonist endothelin-1 and phenylephrine over the Gα12/13-coupled agonist U46619; introduction of the isolated PH domain of p63RhoGEF into permeabilized rabbit portal vein inhibited Ca2+-sensitized force and RhoA activation.\",\n      \"method\": \"siRNA knockdown in mouse portal vein; ex vivo force measurements; permeabilized tissue PH-domain introduction; RhoA activation assays\",\n      \"journal\": \"Circulation research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — endogenous knockdown in intact tissue with functional force readout plus PH-domain dominant-negative experiment, replicated across two agonist systems\",\n      \"pmids\": [\"21885830\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"In rat aortic smooth muscle cells, endogenous p63RhoGEF is the dominant mediator of fast angiotensin II–induced (Gq/11-dependent) RhoA activation; its knockdown abolished ANG II-induced stress fiber formation and cell elongation, reduced the mitogenic response, and impaired ANG II-driven contraction in a 3-D collagen model; p63RhoGEF did not activate Rac1 in this context.\",\n      \"method\": \"siRNA knockdown; RhoA/Rac1 activation assays; 2-D cell morphology; 3-D collagen contraction model; proliferation assay\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — endogenous loss-of-function with multiple orthogonal functional readouts (GTPase activity, morphology, contraction, proliferation)\",\n      \"pmids\": [\"20739613\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"p63RhoGEF binds to constitutively active Gα16QL (a Gαq family member) via Co-IP; overexpressed p63RhoGEF competitively displaces PLCβ2 and TTC1 from Gα16QL, inhibiting IP3 production, Ras activation, STAT3 phosphorylation, and SRE transcriptional activation.\",\n      \"method\": \"Co-immunoprecipitation in HEK293 cells; IP3 production assay; STAT3 phosphorylation; SRE luciferase reporter; competition binding assays\",\n      \"journal\": \"Cellular signalling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 / Moderate — Co-IP plus multiple downstream signaling readouts, single lab\",\n      \"pmids\": [\"19332116\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Pasteurella multocida toxin inhibits osteoblast differentiation via Gαq/11 activation of p63RhoGEF, which activates RhoA; activated RhoA then transactivates the MAP kinase cascade (Rho kinase → Ras → MEK → ERK), blocking osteoblast differentiation; p63RhoGEF does not interact with Gα12/13 or Gαi in this pathway.\",\n      \"method\": \"Primary osteoblast and ST-2 cell differentiation models; alkaline phosphatase assay; mineralization nodule formation; pharmacological inhibitors; siRNA; GTPase activation assays\",\n      \"journal\": \"PLoS pathogens\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — pathway placement via pharmacological inhibitors, siRNA knockdown, and multiple differentiation markers; single lab\",\n      \"pmids\": [\"23696743\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"GPR116 (adhesion GPCR) promotes breast cancer cell migration, invasion, and lamellipodia/stress fiber formation through the Gαq–p63RhoGEF–RhoA/Rac1 pathway; GPR116 knockdown reduces RhoA and Rac1 activation, and p63RhoGEF knockdown phenocopies GPR116 knockdown.\",\n      \"method\": \"siRNA knockdown of GPR116 and p63RhoGEF; RhoA/Rac1 activation assays; cell migration and invasion assays; mouse mammary tumor metastasis models\",\n      \"journal\": \"Cancer research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — epistasis established by double knockdown plus GTPase activation and in vivo metastasis assays, single lab\",\n      \"pmids\": [\"24008316\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"FRET-based live-cell imaging showed that Gαq and p63RhoGEF form a direct, dynamic complex upon GPCR activation; on/off kinetics of the Gαq–p63RhoGEF interaction closely match Gαq activity kinetics; RGS2 accelerates both Gαq deactivation and Gαq–p63RhoGEF complex dissociation; activation-dependent FRET between RGS2 and p63RhoGEF was detected, supporting a functional Gαq–p63RhoGEF–RGS2 complex.\",\n      \"method\": \"FRET (Gαq-CFP/Venus-p63RhoGEF) in single living cells; GPCR stimulation (H1, M3); RGS2 co-expression; downstream signaling assays\",\n      \"journal\": \"The Biochemical journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — FRET-based interaction kinetics in living cells with regulatory perturbation; single lab\",\n      \"pmids\": [\"24299002\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"Three ARHGEF25 isoforms exist (p63RhoGEF580, GEFT, p63RhoGEF619); p63RhoGEF580 is constitutively plasma-membrane-localized while p63RhoGEF619 is cytosolic and translocates to the plasma membrane upon Gαq-coupled GPCR stimulation; both activate RhoA similarly after GPCR stimulation; synthetic membrane recruitment of p63RhoGEF619 increases RhoGEF activity but full activation requires allosteric activation by Gαq, revealing a dual role for Gαq (recruitment + allosteric activation) for cytosolic isoforms.\",\n      \"method\": \"Live-cell imaging; FRET; rapamycin-inducible membrane recruitment; FRAP (diffusion coefficients); RhoA activity FRET biosensor; GPCR stimulation\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — live imaging with multiple quantitative methods; single lab but multiple orthogonal approaches\",\n      \"pmids\": [\"27833100\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"p63RhoGEF (plasma membrane) signals more efficiently downstream of Gαq than GEFT (cytoplasmic); forced membrane recruitment of GEFT via rapamycin-inducible system restores efficient Gαq-mediated signaling; membrane localization increases effective concentration rather than encounter time.\",\n      \"method\": \"Live-cell imaging; FRET-based calcium signaling assay; rapamycin-dependent membrane recruitment; FRAP for diffusion coefficients\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — quantitative live-cell imaging with inducible localization control; single lab\",\n      \"pmids\": [\"23884432\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"GEFT protein is concentrated at actin-enriched regions in retinoic acid-induced primary neurites and at the growth cone tip in cAMP-induced axon-like extensions; GEFT promotes neurite outgrowth in both undifferentiated and differentiated Neuro2A cells.\",\n      \"method\": \"Immunofluorescence/confocal localization in differentiating Neuro2A cells; neurite outgrowth quantification with RA and dbcAMP treatment\",\n      \"journal\": \"Journal of neuroscience research\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — localization by immunofluorescence and overexpression phenotype, no pathway placement or mechanistic follow-up\",\n      \"pmids\": [\"16496360\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"GEFT promotes lens fiber differentiation (cell elongation, lentoid formation, crystallin expression) in N/N1003A lens epithelial cells via a Rac1-dependent mechanism; Rac1 nuclear localization is required; pharmacological inhibition of Rac1 blocks GEFT-induced differentiation in ex vivo mouse lens explants.\",\n      \"method\": \"Transfection of lens epithelial cells; crystallin promoter luciferase assays; Rac1 inhibitor (NSC23766); ex vivo lens explant; immunohistochemistry\",\n      \"journal\": \"Current molecular medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — pharmacological and reporter-based pathway placement with ex vivo validation; single lab\",\n      \"pmids\": [\"21663592\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"In cardiac fibroblasts, p63RhoGEF mediates angiotensin II-dependent RhoA activation, serum response factor activation, and CTGF expression/secretion; p63RhoGEF is localized to the trans-Golgi network in cardiac fibroblasts; its expression in engineered heart/connective tissue models increases tissue stiffness and contractile tension.\",\n      \"method\": \"siRNA knockdown; dominant-negative p63ΔN; RhoA activation assays; SRF reporter; CTGF ELISA; engineered heart muscle and connective tissue models; confocal colocalization\",\n      \"journal\": \"Journal of molecular and cellular cardiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — endogenous knockdown plus dominant-negative, multiple functional readouts in 2D and 3D models; single lab\",\n      \"pmids\": [\"26392029\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"GEFT activates the Rac1/Cdc42-PAK1 signaling pathway to promote EMT (upregulation of N-cadherin, Snail, Slug, Twist, Zeb1, Zeb2; downregulation of E-cadherin) and thereby drives rhabdomyosarcoma invasion and metastasis; GEFT gene promoter hypomethylation is associated with elevated GEFT expression in RMS.\",\n      \"method\": \"RMS cell lines; BALB/c nude mouse xenografts; siRNA/overexpression; active Rac1/Cdc42 assays; EMT marker western blot; bisulfite sequencing for methylation\",\n      \"journal\": \"EBioMedicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — GTPase activation assays and downstream EMT markers with in vivo xenograft validation; single lab\",\n      \"pmids\": [\"31761617\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"GEFT inhibits autophagy and apoptosis in rhabdomyosarcoma cells via Rac1/Cdc42 activation of mTOR; Rac1/Cdc42 inhibition reduces the anti-autophagy/anti-apoptosis effect of GEFT.\",\n      \"method\": \"GEFT overexpression/knockdown in RMS cells; Rac1/Cdc42 inhibitor; autophagy markers (Beclin1, LC3); apoptosis markers (Bcl-2, Bax); mTOR activity assays\",\n      \"journal\": \"Frontiers in oncology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — pharmacological inhibitor-based pathway placement without direct mechanistic demonstration; single lab\",\n      \"pmids\": [\"34221974\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"GNAQ forms a complex with ARHGEF25 (Co-IP) and promotes RhoA activation in NK/T-cell lymphoma; GNAQ T96S mutation abolishes wild-type GNAQ ability to activate the GNAQ-ARHGEF25-RhoA pathway and trigger apoptosis.\",\n      \"method\": \"Co-immunoprecipitation; mRNA sequencing; Western blotting; RhoA pathway activity; CCK-8 and flow cytometry\",\n      \"journal\": \"Cancer biology & therapy\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single Co-IP plus indirect downstream assays; single study with limited mechanistic depth\",\n      \"pmids\": [\"41362935\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Conditional knockout of Geft in the second heart field (using Mef2c-Cre) results in mice that develop normally with no discernible cardiac phenotype, indicating Geft is dispensable for second heart field development.\",\n      \"method\": \"Conditional knockout mouse (loxP-flanked exons 5-17, Mef2c-Cre); cardiac morphology assessment\",\n      \"journal\": \"BMB reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean conditional KO with defined developmental readout; finding is a rigorous negative result\",\n      \"pmids\": [\"22449701\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"ARHGEF25 (p63RhoGEF/GEFT) is a Dbl-family RhoA guanine nucleotide exchange factor that is constitutively palmitoylated at N-terminal cysteines and localized to the plasma membrane; activated Gαq/11 directly binds the C-terminal extension of its PH domain (as revealed by the crystal structure of the Gαq–p63RhoGEF–RhoA ternary complex), relieving autoinhibition of the catalytic DH domain by the PH domain and thereby activating RhoA, which mediates downstream processes including vascular smooth muscle Ca²⁺ sensitization and contraction, actin stress fiber formation, and cardiac fibroblast remodeling; MLK3 acts as a scaffold that binds p63RhoGEF and limits Gαq-mediated RhoA activation, while RGS2 accelerates Gαq–p63RhoGEF dissociation; a longer cytosolic isoform (p63RhoGEF619) requires both membrane recruitment and allosteric activation by Gαq for full activity.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"ARHGEF25 (p63RhoGEF/GEFT) is a Dbl-family guanine nucleotide exchange factor that couples Gαq/11-linked GPCR signaling to Rho-family GTPase activation, controlling actin cytoskeletal remodeling, smooth muscle contraction, and tissue differentiation [#0, #3, #11]. The full-length p63RhoGEF catalyzes GDP/GTP exchange selectively on RhoA in vitro, an activity that requires its PH domain and drives actin stress fiber formation and SRF-mediated transcription [#3, #4]. Activation is governed by an autoinhibitory arrangement in which the PH domain restrains the catalytic DH domain; active Gαq/11 (but not Gα12/13) directly engages a conserved C-terminal extension of the PH domain, relieving this autoinhibition and activating RhoA, as defined by the Gαq–p63RhoGEF–RhoA ternary crystal structure and reconstituted biochemistry [#0, #1, #2]. N-terminal palmitoylation (Cys-23/25/26) targets the protein to the plasma membrane and is required for full basal activity, while a longer cytosolic isoform (p63RhoGEF619) requires both Gαq-driven membrane recruitment and allosteric activation for full activity [#10, #17]. Endogenous p63RhoGEF is the dominant mediator of Gαq/11-coupled agonist (angiotensin II, endothelin-1, phenylephrine)-induced RhoA activation, Ca²⁺-sensitized contractile force, stress fiber formation, and cardiac fibroblast CTGF expression and tissue stiffening [#11, #12, #21]. The pathway is regulated by MLK3, which binds p63RhoGEF and limits Gαq-mediated RhoA activation independent of its kinase activity, and by RGS2, which accelerates Gαq–p63RhoGEF complex dissociation [#9, #16]. The N-terminally truncated GEFT isoform additionally exchanges on Rac1 and Cdc42 in vitro and promotes neurite outgrowth, myogenesis, lens fiber differentiation, and—through Rac1/Cdc42–PAK1 signaling—epithelial–mesenchymal transition in rhabdomyosarcoma, indicating context-dependent substrate usage [#5, #6, #20, #22].\",\n  \"teleology\": [\n    {\n      \"year\": 2002,\n      \"claim\": \"Established the core enzymatic identity: that p63RhoGEF is a RhoA-specific exchange factor requiring its PH domain, answering what GTPase it acts on and where it functions.\",\n      \"evidence\": \"In vitro nucleotide exchange assay, confocal localization, and stress fiber assay in fibroblasts/cardiac myoblasts\",\n      \"pmids\": [\"11861769\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not identify the upstream activating signal\", \"Mechanism of PH-domain requirement unresolved\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Showed that the N-terminally truncated GEFT isoform has exchange activity for Rac1 and Cdc42, introducing the question of isoform-dependent substrate specificity.\",\n      \"evidence\": \"In vitro exchange assay, GST-PAK pull-down, and NIH3T3 focus/migration assays\",\n      \"pmids\": [\"12547822\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Substrate specificity conflicts with RhoA-selective full-length data\", \"Overexpression-based readouts\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Resolved that p63RhoGEF and GEFT are isoforms of one gene and that both activate RhoA and SRF transcription in cells, unifying the gene identity.\",\n      \"evidence\": \"RT-PCR isoform detection, GTPase activation assays, SRF reporter, and C3 transferase inhibition\",\n      \"pmids\": [\"15069594\", \"15322108\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Context-dependence of Rac1/Cdc42 versus RhoA usage not fully reconciled\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Identified the upstream activator: active Gαq/11, but not Gα12/13, directly binds p63RhoGEF and enhances RhoA activation, placing it in Gq-coupled GPCR signaling.\",\n      \"evidence\": \"Co-IP, Gq/11-coupled receptor stimulation, RhoA assays, and dominant-negative Gα mutants; plus C2C12/3T3L1 differentiation models for GEFT\",\n      \"pmids\": [\"15632174\", \"16314529\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of Gαq binding not yet defined\", \"Mechanism of autoinhibition relief unknown\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Defined the activation mechanism at atomic resolution: Gαq engages the PH-domain C-terminal extension to relieve DH-domain autoinhibition, explaining how GPCR signals are transduced to RhoA.\",\n      \"evidence\": \"X-ray crystallography of the Gαq–p63RhoGEF–RhoA ternary complex and reconstituted biochemistry with purified proteins\",\n      \"pmids\": [\"18096806\", \"17606614\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not address membrane targeting requirements\", \"Dynamics in living cells unresolved\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Identified negative regulators: MLK3 scaffolds and limits Gαq-driven activation, and Bves dampens GEFT-mediated Rac1/Cdc42 signaling, revealing regulatory inputs beyond Gαq.\",\n      \"evidence\": \"Co-IP, kinase-dead MLK3 mutants, active GTPase pull-downs, and migration assays\",\n      \"pmids\": [\"18851832\", \"18541910\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab Co-IP for each interaction\", \"Stoichiometry and competition with Gαq not quantified\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Established that palmitoylation-driven plasma membrane localization is required for activity, and demonstrated the endogenous physiological role in vascular smooth muscle Ca²⁺ sensitization.\",\n      \"evidence\": \"Cys→Ser mutagenesis with palmitoylation/fractionation assays plus siRNA knockdown in portal vein with ex vivo force measurements\",\n      \"pmids\": [\"21832057\", \"21885830\", \"20739613\", \"21663592\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Palmitoyl acyltransferase responsible not identified\", \"Tissue specificity of contractile coupling incomplete\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Captured the activation dynamics in living cells and the role of RGS2, showing Gαq–p63RhoGEF complex kinetics track Gαq activity and RGS2 accelerates dissociation.\",\n      \"evidence\": \"FRET imaging in single living cells with GPCR stimulation and RGS2 co-expression; plus pathological pathway placement in osteoblast and breast cancer models\",\n      \"pmids\": [\"24299002\", \"23696743\", \"24008316\", \"23884432\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"FRET interactions are single-lab\", \"Quantitative contribution of RGS2 in vivo unknown\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Distinguished isoform behavior, showing the cytosolic p63RhoGEF619 requires dual Gαq input (recruitment plus allosteric activation) whereas membrane-anchored p63RhoGEF580 is constitutively localized.\",\n      \"evidence\": \"Live-cell imaging, FRET, rapamycin-inducible recruitment, FRAP, and RhoA biosensors\",\n      \"pmids\": [\"27833100\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Physiological role of distinct isoforms in tissues not established\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Extended the Gαq–ARHGEF25–RhoA axis to disease, linking a GNAQ mutation to loss of pathway activation and apoptosis in NK/T-cell lymphoma.\",\n      \"evidence\": \"Co-IP, RhoA pathway assays, and apoptosis readouts in lymphoma cells; plus EMT/autophagy roles in rhabdomyosarcoma\",\n      \"pmids\": [\"41362935\", \"31761617\", \"34221974\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Single Co-IP without reciprocal validation\", \"Mechanism of mutation-dependent loss not structurally resolved\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How the conflicting RhoA versus Rac1/Cdc42 substrate selectivity of full-length and truncated isoforms is determined in physiological contexts, and what endogenous loss-of-function reveals beyond the second heart field, remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No in vivo whole-organism phenotype beyond a dispensable second-heart-field knockout (22449701)\", \"Structural basis of isoform-specific substrate switching unknown\", \"Endogenous determinants of Rac1/Cdc42 versus RhoA usage uncharacterized\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [3, 5, 9]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [3, 0, 1]},\n      {\"term_id\": \"GO:0060089\", \"supporting_discovery_ids\": [0, 2, 11]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [10, 17, 11]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [10, 17, 18]},\n      {\"term_id\": \"GO:0005794\", \"supporting_discovery_ids\": [21]},\n      {\"term_id\": \"GO:0005856\", \"supporting_discovery_ids\": [3, 19]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 2, 11]},\n      {\"term_id\": \"R-HSA-397014\", \"supporting_discovery_ids\": [11, 12]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [6, 7, 20]}\n    ],\n    \"complexes\": [\"Gαq–p63RhoGEF–RhoA ternary complex\"],\n    \"partners\": [\"GNAQ\", \"GNA11\", \"RHOA\", \"MLK3\", \"RGS2\", \"BVES\", \"GPR116\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}