{"gene":"ARFGEF2","run_date":"2026-06-09T22:02:44","timeline":{"discoveries":[{"year":2003,"finding":"ARFGEF2/BIG2 is required for vesicle and membrane trafficking from the trans-Golgi network (TGN); inhibition by brefeldin A or dominant-negative ARFGEF2 cDNA decreases neural progenitor cell proliferation in vitro and disrupts intracellular localization of E-cadherin and beta-catenin by preventing their transport from the Golgi apparatus to the cell surface.","method":"Dominant-negative cDNA expression, brefeldin A inhibition, cell proliferation assays, immunofluorescence localization of E-cadherin and beta-catenin in cultured cells","journal":"Nature genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (dominant-negative, pharmacological inhibition, proliferation assay, trafficking assay) in a single rigorous study with clear phenotypic readouts","pmids":["14647276"],"is_preprint":false},{"year":2002,"finding":"BIG2 overexpression blocks BFA-induced redistribution of ARF1 and the AP-1 complex from TGN membranes but not the COPI complex, indicating BIG2 specifically regulates membrane association of AP-1 (but not COPI) through ARF activation at the TGN.","method":"Overexpression of BIG2 in cells, BFA treatment, immunofluorescence redistribution assays for ARF1, AP-1, and COPI coat proteins","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — cell-based gain-of-function with multiple coat protein readouts, single lab","pmids":["11777925"],"is_preprint":false},{"year":2002,"finding":"A dominant-negative BIG2 mutant induces redistribution of AP-1 and GGA1 coat proteins and membrane tubulation of the TGN, but does not affect COPI redistribution or Golgi tubulation, placing BIG2 specifically in the TGN-to-endosome trafficking pathway via AP-1 and GGA regulation.","method":"Dominant-negative BIG2 mutant expression, immunofluorescence for AP-1, GGA1, COPI, organelle markers","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — dominant-negative approach with multiple coat protein readouts, single lab, consistent with companion paper","pmids":["12051703"],"is_preprint":false},{"year":2004,"finding":"BIG2 localizes to both the TGN and recycling endosomes; expression of a catalytically inactive BIG2 mutant (E738K) selectively induces membrane tubules from the recycling endosome compartment. BIG2 has exchange activity toward class I ARFs (ARF1 and ARF3) in vivo, and inactivation of either ARF exaggerates tubulation induced by BIG2(E738K), indicating BIG2 maintains recycling endosome integrity via class I ARF activation.","method":"Catalytically inactive mutant (E738K) expression, immunofluorescence, ARF1/ARF3 inactivation epistasis, subcellular fractionation/localization","journal":"Molecular biology of the cell","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — active-site mutagenesis combined with genetic epistasis (ARF1/ARF3 inactivation) and localization, multiple orthogonal methods in one study","pmids":["15385626"],"is_preprint":false},{"year":2003,"finding":"BIG2 contains three A kinase-anchoring protein (AKAP) domains in its N-terminal region: domain A (residues 27–48) interacts with RI-alpha and RI-beta; domain B (284–301) interacts with RII-alpha and RII-beta; domain C (517–538) interacts with RI-alpha, RII-alpha, and RII-beta. BIG2 physically interacts with the PKA regulatory subunit RI-alpha, confirmed by coimmunoprecipitation of in vitro translated proteins and endogenous proteins. Elevation of cAMP (8-Br-cAMP or forskolin) induces translocation of BIG2 from cytosol to Golgi and other membranes.","method":"Yeast two-hybrid screen, coimmunoprecipitation of in vitro translated and endogenous proteins, 28 deletion mutants, Western blot subcellular fractionation","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — yeast two-hybrid confirmed by reciprocal Co-IP of endogenous proteins, systematic domain mapping with 28 deletion mutants, multiple orthogonal methods","pmids":["12571360"],"is_preprint":false},{"year":2005,"finding":"BIG2 physically interacts with exocyst protein Exo70 via its N-terminal region (amino acids 1–643); both BIG2 and Exo70 co-localize at trans-Golgi network membranes and at the microtubule-organizing center (MTOC)/centrosomes in HepG2 cells, suggesting functional association in vesicular trafficking from TGN to plasma membrane.","method":"Yeast two-hybrid screen, coimmunoprecipitation of in vitro translated proteins, immunofluorescence confocal microscopy, centrosome purification","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — yeast two-hybrid confirmed by Co-IP and co-localization, single lab","pmids":["15705715"],"is_preprint":false},{"year":2006,"finding":"BIG2 localizes specifically (not BIG1) to recycling endosome structures during transferrin uptake and transferrin receptor (TfnR) recycling in COS7 cells. BIG2 siRNA knockdown causes perinuclear accumulation of TfnR and significantly slows transferrin release, demonstrating a functional role for BIG2 in TfnR recycling. BIG2 interacts with Exo70 in recycling endosome fractions.","method":"Immunofluorescence microscopy, density-gradient fractionation, siRNA knockdown, transferrin recycling assay","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 / Strong — siRNA knockdown with functional trafficking readout, density-gradient fractionation, and localization; multiple orthogonal methods, replicated localization from prior study","pmids":["16477018"],"is_preprint":false},{"year":2006,"finding":"BIG2 (but not BIG1) is required for trafficking of Filamin A (FLNA) from the Golgi apparatus to the cell membrane in neuroblastoma cells; transfection of dominant-negative ARFGEF2 partially blocks FLNA transport. BIG2 and FLNA are co-expressed in neural progenitors along the neuroependyma.","method":"Dominant-negative ARFGEF2 transfection, immunofluorescence for FLNA localization, Western blot co-expression","journal":"The Journal of comparative neurology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — dominant-negative functional assay with specific cargo (FLNA) readout, single lab","pmids":["16320251"],"is_preprint":false},{"year":2007,"finding":"BIG2 (not BIG1) regulates constitutive release of TNFR1 exosome-like vesicles from human vascular endothelial cells via an ARF1- and ARF3-dependent mechanism. BIG2 co-localizes with TNFR1 in cytoplasmic vesicles, and this association is disrupted by BFA. ARF1 and ARF3 act nonredundantly and additively in TNFR1 exosome-like vesicle release.","method":"RNA interference (specific siRNA for BIG1, BIG2, ARF1, ARF3), TNFR1 release assay, immunofluorescence co-localization, BFA disruption","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — siRNA with functional release assay and mechanistic dissection of ARF isoforms, multiple orthogonal approaches, single lab but rigorous","pmids":["17276987"],"is_preprint":false},{"year":2007,"finding":"PKA phosphorylates BIG2 in vitro, decreasing its GEP activity; this phosphorylation is reversed by protein phosphatase 1gamma (PP1gamma) but not PP1alpha or PP1beta. Endogenous PP1gamma (not PP1alpha or PP1beta) co-immunoprecipitates with BIG2 from microsomal fractions, establishing PP1gamma as a regulator of BIG2 activity.","method":"In vitro PKA phosphorylation assay, siRNA depletion of BIG2, immunoprecipitation GEP activity assay, recombinant phosphatase treatment, Co-IP of PP1 isoforms","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro kinase and phosphatase assays combined with endogenous Co-IP and siRNA depletion, multiple orthogonal methods in one study","pmids":["17360629"],"is_preprint":false},{"year":2006,"finding":"AMY-1 (associate of Myc-1) co-immunoprecipitates with both BIG2 and BIG1 in vitro, but localizes to the TGN specifically through interaction with BIG2 (not BIG1) as demonstrated by RNAi: depletion of BIG2 (not BIG1) disperses AMY-1 from the TGN.","method":"Co-immunoprecipitation using FLAG-tagged AMY-1, siRNA knockdown of BIG1 or BIG2, immunofluorescence localization of AMY-1","journal":"Genes to cells : devoted to molecular & cellular mechanisms","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP combined with siRNA functional localization assay, single lab","pmids":["16866877"],"is_preprint":false},{"year":2007,"finding":"BIG2 (and BIG1) form homodimers through interactions between their conserved DCB domains; within each homodimer, the DCB domain also interacts with the HUS domain. The HUS box is the most conserved motif in large ArfGEFs after the Sec7 domain and mediates the DCB/HUS interaction.","method":"Yeast two-hybrid assays, biochemical interaction assays, deletion mutant analysis, cellular dimerization assays in mammalian cells","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — yeast two-hybrid confirmed by biochemical assays and cellular dimerization assays, single lab with multiple methods","pmids":["17640864"],"is_preprint":false},{"year":2008,"finding":"Simultaneous knockdown of both BIG2 and BIG1 causes mislocalization of TGN/recycling endosome-associated proteins and blocks retrograde transport of furin from late endosomes to the TGN, a phenotype similar to depletion of AP-1, establishing BIG2 and BIG1 as redundant regulators of AP-1-dependent trafficking between TGN and endosomes.","method":"RNAi double knockdown, immunofluorescence localization of furin and TGN markers, comparison to AP-1 depletion","journal":"Molecular biology of the cell","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — RNAi double knockdown with genetic epistasis comparison to AP-1 depletion, single lab","pmids":["18417613"],"is_preprint":false},{"year":2008,"finding":"cAMP-induced release of TNFR1 exosome-like vesicles requires PKA activity and is mediated through BIG2's AKAP function: PKA regulatory subunit RIIbeta binds specifically to BIG2 AKAP domains B and C, and this interaction is required for both constitutive and cAMP-induced TNFR1 exosome-like vesicle release.","method":"siRNA knockdown of PKA regulatory subunits (RIIbeta), TNFR1 release assay, domain mapping of BIG2 AKAP sequences, 8-bromo-cAMP stimulation","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — siRNA with functional assay and domain mapping, single lab, builds directly on prior BIG2/TNFR1 study","pmids":["18625701"],"is_preprint":false},{"year":2009,"finding":"Phosphodiesterase 3A (PDE3A) physically associates with BIG2 (and BIG1) complexes; specific depletion of PDE3A by siRNA or its inhibition by cilostamide significantly decreases membrane-associated BIG2 and BIG1 and reduces activated ARF1-GTP, linking PDE3A-dependent cAMP regulation within BIG2 AKAP complexes to ARF1 activation.","method":"siRNA depletion of PDE3A, PDE3A-specific inhibitor cilostamide, confocal immunofluorescence, ARF1-GTP measurement","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — siRNA and pharmacological inhibition with ARF activation readout, single lab","pmids":["19332778"],"is_preprint":false},{"year":2010,"finding":"Depletion of BIG2 (but not BIG1) by siRNA induces tubulation of the recycling endosomal compartment, while BIG1 depletion causes Golgi fragmentation into mini-stacks; this demonstrates non-redundant and distinct functions for BIG2 (recycling endosome integrity) vs. BIG1 (Golgi morphology).","method":"siRNA knockdown, fixed and live-cell fluorescence imaging of Golgi and endosomal markers","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — siRNA with live and fixed imaging, comparative study of BIG1 vs BIG2, single lab","pmids":["20360857"],"is_preprint":false},{"year":2012,"finding":"The small G protein Arl1 is necessary and sufficient for Golgi recruitment of BIG2 (and BIG1) but not GBF1. Arl1 binds directly to the N-terminal region of Sec71 (the Drosophila ortholog of BIG1/BIG2), establishing Arl1 as the upstream recruiter that directs BIG2 specifically to the trans-Golgi.","method":"Liposome-based affinity purification to identify Arl1 effectors, Arl1 knockdown in mammalian cells, immunofluorescence of BIG1/BIG2/GBF1 Golgi localization","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — novel liposome-based affinity purification for direct binding combined with mammalian cell Arl1 knockdown functional localization, orthologous validation in Drosophila","pmids":["22291037"],"is_preprint":false},{"year":2012,"finding":"BIG2 siRNA depletion causes perinuclear accumulation of integrin beta1 and delayed return to the cell surface, decreased cell motility, and reduced actin-based membrane protrusions; cytosolic levels of Arp2, Arp3, cofilin-1, phosphocofilin, vinculin, and Grb2 are increased, establishing BIG2 as a regulator of integrin beta1 recycling and actin dynamics in cell migration.","method":"siRNA knockdown, difference gel electrophoresis (DIGE) proteomics, immunofluorescence, wound-healing migration assay, integrin beta1 trafficking assay","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — siRNA with proteomics, migration assay, and integrin trafficking assay; single lab, multiple orthogonal readouts","pmids":["22908276"],"is_preprint":false},{"year":2013,"finding":"GBF1-activated ARFs (ARF4 and ARF5, but not ARF3) facilitate BIG2 and BIG1 recruitment to the TGN, establishing a functional GEF cascade: GBF1 (pre-Golgi/Golgi/TGN) → ARF4/ARF5 activation → BIG1/BIG2 TGN recruitment → ARF activation for AP-1/GGA clathrin adaptor recruitment.","method":"GBF1 dominant-negative expression, ARF isoform-specific depletion, immunofluorescence of BIG1/BIG2 TGN localization, ultrastructural localization by immuno-EM","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — dominant-negative and ARF knockdown epistasis with ultrastructural validation, single lab","pmids":["23386609"],"is_preprint":false},{"year":2013,"finding":"BIG2 physically associates (reciprocal Co-IP) with nonmuscle myosin IIA in HeLa cells independently of its ARF-GEF activity; depletion of BIG2 (or BIG1) enhances phosphorylation of myosin regulatory light chain (T18/S19) and increases F-actin content, impairing cell migration. BIG2 anchors a myosin phosphatase complex containing myosin IIA, protein phosphatase 1delta, and myosin phosphatase-targeting subunit 1 (MYPT1).","method":"Reciprocal Co-IP of endogenous proteins, siRNA depletion, phospho-myosin light chain measurement, F-actin quantification, Transwell cell migration assay, rescue by BIG2 C-terminal overexpression","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — reciprocal endogenous Co-IP, siRNA depletion, rescue experiments, multiple functional readouts (phosphorylation, F-actin, migration), single lab but comprehensive","pmids":["23918382"],"is_preprint":false},{"year":2016,"finding":"BIG2 (and BIG1) physically interact with beta-catenin; depletion of BIG1/BIG2 or expression of GEF-inactive mutants causes perinuclear Golgi accumulation of beta-catenin and reduces PKA-phosphorylated beta-catenin (S675). BIG2 AKAP-C sequence is required for PKA-dependent S675 phosphorylation and beta-catenin transcription coactivator function, requiring both ARF-GEF activity and phospholipase D-dependent vesicular trafficking.","method":"Co-IP (BIG1/BIG2 antibodies), yeast two-hybrid, in vitro protein synthesis, siRNA depletion, GEF-inactive mutant expression, phospho-beta-catenin Western blot, transcription reporter assay","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — yeast two-hybrid confirmed by Co-IP and functional assays, single lab with multiple orthogonal methods","pmids":["27162341"],"is_preprint":false},{"year":2018,"finding":"BIG2 co-localizes with the Golgi apparatus in hippocampal neurons and is required for Golgi deployment into major dendrites. BIG2 acts through ARF1 to activate RhoA and its downstream effector mDia1, forming a BIG2-ARF1-RhoA-mDia1 signaling axis that regulates dendritic Golgi polarization and dendrite growth/maintenance. In vivo, ARFGEF2 shRNA delivered by in utero electroporation impairs Golgi deployment into the apical dendrite.","method":"shRNA knockdown, constitutively active ARF1 Q71L rescue, RhoA activation assay, LPA treatment rescue, immunofluorescence, in utero electroporation in mouse embryos","journal":"Molecular neurobiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — shRNA with epistasis rescue experiments (ARF1 Q71L, RhoA activator), in vivo validation by in utero electroporation, single lab","pmids":["29455446"],"is_preprint":false},{"year":2019,"finding":"BIG2 (and BIG1) knockdown significantly decreases VEGF mRNA and protein levels in glioblastoma U251 cells and HUVECs, and inhibits HUVEC angiogenesis by diminishing cell migration. Knockdown of the BIG2 homolog arfgef2 in zebrafish impairs angioblast migration and intersegmental vessel sprouting, and CRISPR/Cas9 deletion of arfgef2 causes vascular development defects, establishing a role for BIG2 in VEGF expression and angiogenesis beyond vesicular trafficking.","method":"siRNA knockdown, VEGF mRNA/protein quantification, HUVEC migration and angiogenesis assays, zebrafish morpholino knockdown and CRISPR/Cas9 deletion with vascular GFP imaging","journal":"FASEB journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — siRNA and CRISPR/Cas9 in zebrafish with functional angiogenesis readouts, single lab with in vitro and in vivo validation","pmids":["31199673"],"is_preprint":false},{"year":2025,"finding":"In Drosophila neuroblasts, Arf1 and its GEF ARFGEF2/Sec71 control asymmetric division by facilitating cortical localization of nonmuscle myosin II regulatory light chain (Sqh). Arf1 physically associates with Sqh and with Vibrator (a type I PITP), and Arf1/Sec71 facilitate PI(4)P localization to the neuroblast cortex, linking PI(4)P production to myosin II cortical anchoring during asymmetric division.","method":"Genetic epistasis in Drosophila, Co-immunoprecipitation of Arf1 with Sqh and Vibrator, immunofluorescence of PI(4)P and myosin II cortical localization, loss-of-function neuroblast division assays","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP combined with in vivo genetic epistasis in Drosophila, single study; ortholog of ARFGEF2 (Sec71) in a model organism","pmids":["40208939"],"is_preprint":false}],"current_model":"ARFGEF2/BIG2 is a large (~200 kDa) brefeldin A-sensitive guanine nucleotide exchange factor (GEF) for class I ARFs (ARF1 and ARF3) that localizes to the trans-Golgi network (TGN) and recycling endosomes, where it activates ARFs to recruit AP-1/GGA clathrin adaptors and maintain organelle integrity; it is recruited to the TGN by Arl1 (downstream of a GBF1→ARF4/5 cascade), functions as an A kinase-anchoring protein (AKAP) that coordinates PKA and PP1gamma signaling to regulate its own GEF activity, scaffolds myosin phosphatase complexes to control actomyosin dynamics and cell migration, regulates integrin beta1 and TNFR1 exosome-like vesicle recycling, modulates beta-catenin trafficking and transcriptional activity, and drives dendritic Golgi polarization via a BIG2-ARF1-RhoA-mDia1 axis in neurons."},"narrative":{"mechanistic_narrative":"ARFGEF2 (BIG2) is a brefeldin A-sensitive guanine nucleotide exchange factor that activates class I ARFs (ARF1 and ARF3) to drive membrane trafficking at the trans-Golgi network (TGN) and recycling endosomes, and through this activity it controls cargo delivery, organelle integrity, and several downstream signaling outputs [PMID:14647276, PMID:15385626]. By activating ARFs at the TGN, BIG2 recruits the clathrin adaptors AP-1 and GGA — but not the COPI coat — placing it specifically in the TGN-to-endosome arm of membrane traffic, and it acts redundantly with its homolog BIG1 in AP-1-dependent retrograde transport while retaining a non-redundant role in maintaining recycling endosome integrity [PMID:11777925, PMID:12051703, PMID:18417613, PMID:20360857]. Its catalytic activity is required for recycling of cargoes including the transferrin receptor and integrin beta1, and for release of TNFR1 exosome-like vesicles, and BIG2 transports E-cadherin, beta-catenin, and Filamin A from the Golgi to the cell surface [PMID:14647276, PMID:15385626, PMID:16477018, PMID:16320251, PMID:17276987, PMID:22908276]. BIG2 is recruited to the TGN by the small G protein Arl1 acting downstream of a GBF1→ARF4/ARF5 cascade, and it homodimerizes through an intramolecular DCB/HUS interaction [PMID:22291037, PMID:23386609, PMID:17640864]. Beyond catalysis, BIG2 functions as an A-kinase-anchoring protein (AKAP) with three N-terminal domains that bind PKA regulatory subunits; PKA phosphorylation lowers its GEF activity and is reversed by PP1gamma, and this AKAP/cAMP module — also engaging PDE3A — couples BIG2 to TNFR1 vesicle release and beta-catenin S675 phosphorylation and transcriptional coactivation [PMID:12571360, PMID:17360629, PMID:18625701, PMID:19332778, PMID:27162341]. BIG2 additionally scaffolds a myosin phosphatase complex (myosin IIA, PP1delta, MYPT1) independently of its GEF activity to control myosin light-chain phosphorylation, F-actin content, and cell migration, and drives a BIG2-ARF1-RhoA-mDia1 axis governing dendritic Golgi polarization in neurons [PMID:23918382, PMID:29455446]. BIG2 is also required for VEGF expression and angiogenesis [PMID:31199673].","teleology":[{"year":2002,"claim":"Established that BIG2 selectively controls the membrane association of the AP-1/GGA clathrin adaptors at the TGN rather than the COPI coat, defining which trafficking step it serves.","evidence":"BIG2 overexpression and dominant-negative mutant expression with immunofluorescence redistribution of ARF1, AP-1, GGA1, and COPI in cells","pmids":["11777925","12051703"],"confidence":"Medium","gaps":["Did not establish direct catalytic GEF activity toward specific ARF isoforms","Cargo specificity of the AP-1/GGA pathway not defined"]},{"year":2003,"claim":"Showed BIG2-dependent TGN trafficking is needed for neural progenitor proliferation and for surface delivery of E-cadherin and beta-catenin, linking the GEF to a physiological/developmental output.","evidence":"Dominant-negative cDNA, brefeldin A inhibition, proliferation and immunolocalization assays in cultured cells","pmids":["14647276"],"confidence":"High","gaps":["Did not resolve direct vs indirect effect on cargo transport","ARF isoform specificity not addressed"]},{"year":2003,"claim":"Identified BIG2 as an AKAP with three mapped PKA-regulatory-subunit-binding domains whose membrane recruitment responds to cAMP, defining a non-catalytic scaffolding function.","evidence":"Yeast two-hybrid, reciprocal Co-IP of endogenous proteins, 28 deletion mutants, subcellular fractionation with cAMP elevation","pmids":["12571360"],"confidence":"High","gaps":["Did not show how PKA anchoring feeds back on GEF activity","Functional consequence of cAMP-induced translocation not established"]},{"year":2004,"claim":"Defined BIG2 catalytic specificity toward class I ARFs (ARF1/ARF3) and demonstrated via active-site mutagenesis and ARF epistasis that it maintains recycling endosome integrity.","evidence":"Catalytically inactive E738K mutant, ARF1/ARF3 inactivation epistasis, localization in cells","pmids":["15385626"],"confidence":"High","gaps":["Mechanism distinguishing TGN vs recycling endosome pools not resolved","Recruitment determinants to each compartment not defined"]},{"year":2005,"claim":"Linked BIG2 to the exocyst by identifying an N-terminal Exo70 interaction and shared TGN/centrosomal localization, extending its reach toward plasma-membrane-directed traffic.","evidence":"Yeast two-hybrid, Co-IP of in vitro translated proteins, confocal microscopy, centrosome purification in HepG2 cells","pmids":["15705715"],"confidence":"Medium","gaps":["Functional consequence of Exo70 binding not tested","Endogenous interaction not confirmed in this study"]},{"year":2006,"claim":"Demonstrated a non-redundant, BIG2-specific role (distinct from BIG1) in transferrin receptor recycling and in trafficking the cytoskeletal cargo Filamin A, plus TGN anchoring of AMY-1.","evidence":"siRNA knockdown with transferrin recycling assay and density-gradient fractionation; dominant-negative FLNA trafficking assay; reciprocal Co-IP and RNAi for AMY-1 localization","pmids":["16477018","16320251","16866877"],"confidence":"High","gaps":["Molecular basis for BIG2 vs BIG1 cargo discrimination unresolved","Direct GEF-cargo coupling not established"]},{"year":2007,"claim":"Connected BIG2 GEF activity to a secretory output (TNFR1 exosome-like vesicle release) via nonredundant ARF1/ARF3 action, and established the PKA/PP1gamma phosphoregulatory loop controlling BIG2 catalysis.","evidence":"Isoform-specific siRNA with TNFR1 release assay and BFA disruption; in vitro PKA phosphorylation/GEP activity assay, recombinant PP1 isoform treatment, endogenous Co-IP","pmids":["17276987","17360629"],"confidence":"High","gaps":["In vivo relevance of PKA/PP1gamma regulation not shown","Site of phosphorylation on BIG2 not mapped"]},{"year":2007,"claim":"Defined the structural basis of BIG2 self-association through DCB-mediated homodimerization and an intramolecular DCB/HUS interaction.","evidence":"Yeast two-hybrid, biochemical interaction and deletion-mutant analysis, cellular dimerization assays","pmids":["17640864"],"confidence":"Medium","gaps":["No structural model of the dimer","Functional requirement of dimerization for GEF activity untested"]},{"year":2008,"claim":"Established BIG2/BIG1 redundancy in AP-1-dependent retrograde furin transport and showed cAMP-induced TNFR1 vesicle release operates through BIG2 AKAP domains binding RIIbeta.","evidence":"RNAi double knockdown with furin localization vs AP-1 depletion comparison; PKA subunit siRNA, TNFR1 release assay, AKAP domain mapping","pmids":["18417613","18625701"],"confidence":"Medium","gaps":["Degree of redundancy across cargoes not generalized","Mechanism coupling AKAP-bound PKA to ARF activation incomplete"]},{"year":2009,"claim":"Placed PDE3A within BIG2 AKAP complexes as a cAMP-degrading regulator required for membrane association of BIG2 and ARF1 activation.","evidence":"PDE3A siRNA and cilostamide inhibition, confocal microscopy, ARF1-GTP measurement","pmids":["19332778"],"confidence":"Medium","gaps":["Direct vs indirect PDE3A-BIG2 interaction not resolved","Cargo-level consequences not measured"]},{"year":2010,"claim":"Distinguished non-redundant morphological roles: BIG2 depletion tubulates recycling endosomes while BIG1 depletion fragments the Golgi.","evidence":"siRNA knockdown with fixed and live-cell imaging of Golgi and endosomal markers","pmids":["20360857"],"confidence":"Medium","gaps":["Molecular determinants of compartment-specific action unknown"]},{"year":2012,"claim":"Identified Arl1 as the upstream small G protein necessary and sufficient to recruit BIG2 to the TGN, defining how the GEF is targeted to its compartment.","evidence":"Liposome-based affinity purification, Arl1 knockdown in mammalian cells, Drosophila Sec71 ortholog binding, immunofluorescence","pmids":["22291037"],"confidence":"High","gaps":["How Arl1 recruitment is itself initiated unresolved at this step","Recycling endosome recruitment mechanism not addressed"]},{"year":2012,"claim":"Extended BIG2's recycling function to integrin beta1 and linked it to actin dynamics and cell motility through proteomic and migration readouts.","evidence":"siRNA knockdown, DIGE proteomics, integrin beta1 trafficking and wound-healing migration assays","pmids":["22908276"],"confidence":"Medium","gaps":["Direct mechanism connecting integrin recycling to actin regulators not defined","GEF dependence of the migration phenotype not isolated"]},{"year":2013,"claim":"Positioned BIG2 in a GEF cascade (GBF1→ARF4/ARF5→BIG2 recruitment) and revealed a GEF-independent scaffolding role anchoring a myosin phosphatase complex that controls actomyosin and migration.","evidence":"GBF1 dominant-negative and ARF-isoform depletion with immuno-EM; reciprocal endogenous Co-IP of myosin IIA, siRNA, phospho-MLC and F-actin assays, Transwell migration, C-terminal rescue","pmids":["23386609","23918382"],"confidence":"High","gaps":["How catalytic and scaffolding functions are coordinated within one molecule unclear","Structural basis of myosin phosphatase anchoring not defined"]},{"year":2016,"claim":"Connected BIG2 trafficking and AKAP function to beta-catenin biology, showing it controls beta-catenin Golgi exit, PKA-dependent S675 phosphorylation, and transcriptional coactivation.","evidence":"Co-IP, yeast two-hybrid, siRNA, GEF-inactive mutants, phospho-beta-catenin Western blot, transcription reporter assays","pmids":["27162341"],"confidence":"Medium","gaps":["Direct vs trafficking-mediated effect on beta-catenin phosphorylation not fully separated","Target gene specificity not mapped"]},{"year":2018,"claim":"Defined a neuronal BIG2-ARF1-RhoA-mDia1 axis required for dendritic Golgi polarization and dendrite growth, validated in vivo.","evidence":"shRNA knockdown, ARF1 Q71L and LPA rescue, RhoA activation assay, immunofluorescence, in utero electroporation in mouse","pmids":["29455446"],"confidence":"Medium","gaps":["How ARF1 activates RhoA mechanistically not resolved","Behavioral/developmental consequences not assessed"]},{"year":2019,"claim":"Revealed a role for BIG2 in VEGF expression and angiogenesis, extending its function beyond intracellular trafficking, with in vivo zebrafish validation.","evidence":"siRNA, VEGF mRNA/protein quantification, HUVEC migration/angiogenesis assays, zebrafish morpholino and CRISPR/Cas9 deletion with vascular imaging","pmids":["31199673"],"confidence":"Medium","gaps":["Mechanism linking BIG2 to VEGF transcription not defined","Whether the angiogenesis role is GEF-dependent unclear"]},{"year":2025,"claim":"Showed in a Drosophila ortholog context that Arf1/Sec71 anchor cortical myosin II during asymmetric neuroblast division by directing PI(4)P localization, linking lipid production to actomyosin organization.","evidence":"Drosophila genetic epistasis, Co-IP of Arf1 with Sqh and Vibrator, PI(4)P and myosin II cortical imaging, loss-of-function division assays","pmids":["40208939"],"confidence":"Medium","gaps":["Conservation of the PI(4)P-myosin mechanism in mammalian ARFGEF2 not tested","Direct ARFGEF2 (vs Arf1) requirement in this lipid pathway not isolated"]},{"year":null,"claim":"How BIG2 integrates its catalytic ARF-GEF activity, AKAP/cAMP phosphoregulation, and GEF-independent myosin phosphatase scaffolding into a single coordinated program across distinct compartments and cell types remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No integrated structural model of full-length BIG2 with its partners","Mechanism switching BIG2 between catalytic and scaffolding modes unknown","In vivo relevance of most regulatory loops not established in mammals"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[3,1,16]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[4,19,9]}],"localization":[{"term_id":"GO:0005768","term_label":"endosome","supporting_discovery_ids":[3,6,15]},{"term_id":"GO:0005815","term_label":"microtubule organizing center","supporting_discovery_ids":[5]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[4]}],"pathway":[{"term_id":"R-HSA-5653656","term_label":"Vesicle-mediated transport","supporting_discovery_ids":[0,1,2,6,12]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[9,20,21]},{"term_id":"R-HSA-9609507","term_label":"Protein localization","supporting_discovery_ids":[3,7,8,17]}],"complexes":["myosin phosphatase complex (myosin IIA / PP1delta / MYPT1)","BIG2 AKAP-PKA complex"],"partners":["ARF1","ARF3","ARL1","EXO70","MYH9 (NONMUSCLE MYOSIN IIA)","PPP1CC (PP1GAMMA)","PDE3A","CTNNB1 (BETA-CATENIN)"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9Y6D5","full_name":"Brefeldin A-inhibited guanine nucleotide-exchange protein 2","aliases":["ADP-ribosylation factor guanine nucleotide-exchange factor 2"],"length_aa":1785,"mass_kda":202.0,"function":"Promotes guanine-nucleotide exchange on ARF1 and ARF3 and to a lower extent on ARF5 and ARF6. 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inhibition by brefeldin A or dominant-negative ARFGEF2 cDNA decreases neural progenitor cell proliferation in vitro and disrupts intracellular localization of E-cadherin and beta-catenin by preventing their transport from the Golgi apparatus to the cell surface.\",\n      \"method\": \"Dominant-negative cDNA expression, brefeldin A inhibition, cell proliferation assays, immunofluorescence localization of E-cadherin and beta-catenin in cultured cells\",\n      \"journal\": \"Nature genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (dominant-negative, pharmacological inhibition, proliferation assay, trafficking assay) in a single rigorous study with clear phenotypic readouts\",\n      \"pmids\": [\"14647276\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"BIG2 overexpression blocks BFA-induced redistribution of ARF1 and the AP-1 complex from TGN membranes but not the COPI complex, indicating BIG2 specifically regulates membrane association of AP-1 (but not COPI) through ARF activation at the TGN.\",\n      \"method\": \"Overexpression of BIG2 in cells, BFA treatment, immunofluorescence redistribution assays for ARF1, AP-1, and COPI coat proteins\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — cell-based gain-of-function with multiple coat protein readouts, single lab\",\n      \"pmids\": [\"11777925\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"A dominant-negative BIG2 mutant induces redistribution of AP-1 and GGA1 coat proteins and membrane tubulation of the TGN, but does not affect COPI redistribution or Golgi tubulation, placing BIG2 specifically in the TGN-to-endosome trafficking pathway via AP-1 and GGA regulation.\",\n      \"method\": \"Dominant-negative BIG2 mutant expression, immunofluorescence for AP-1, GGA1, COPI, organelle markers\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — dominant-negative approach with multiple coat protein readouts, single lab, consistent with companion paper\",\n      \"pmids\": [\"12051703\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"BIG2 localizes to both the TGN and recycling endosomes; expression of a catalytically inactive BIG2 mutant (E738K) selectively induces membrane tubules from the recycling endosome compartment. BIG2 has exchange activity toward class I ARFs (ARF1 and ARF3) in vivo, and inactivation of either ARF exaggerates tubulation induced by BIG2(E738K), indicating BIG2 maintains recycling endosome integrity via class I ARF activation.\",\n      \"method\": \"Catalytically inactive mutant (E738K) expression, immunofluorescence, ARF1/ARF3 inactivation epistasis, subcellular fractionation/localization\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — active-site mutagenesis combined with genetic epistasis (ARF1/ARF3 inactivation) and localization, multiple orthogonal methods in one study\",\n      \"pmids\": [\"15385626\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"BIG2 contains three A kinase-anchoring protein (AKAP) domains in its N-terminal region: domain A (residues 27–48) interacts with RI-alpha and RI-beta; domain B (284–301) interacts with RII-alpha and RII-beta; domain C (517–538) interacts with RI-alpha, RII-alpha, and RII-beta. BIG2 physically interacts with the PKA regulatory subunit RI-alpha, confirmed by coimmunoprecipitation of in vitro translated proteins and endogenous proteins. Elevation of cAMP (8-Br-cAMP or forskolin) induces translocation of BIG2 from cytosol to Golgi and other membranes.\",\n      \"method\": \"Yeast two-hybrid screen, coimmunoprecipitation of in vitro translated and endogenous proteins, 28 deletion mutants, Western blot subcellular fractionation\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — yeast two-hybrid confirmed by reciprocal Co-IP of endogenous proteins, systematic domain mapping with 28 deletion mutants, multiple orthogonal methods\",\n      \"pmids\": [\"12571360\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"BIG2 physically interacts with exocyst protein Exo70 via its N-terminal region (amino acids 1–643); both BIG2 and Exo70 co-localize at trans-Golgi network membranes and at the microtubule-organizing center (MTOC)/centrosomes in HepG2 cells, suggesting functional association in vesicular trafficking from TGN to plasma membrane.\",\n      \"method\": \"Yeast two-hybrid screen, coimmunoprecipitation of in vitro translated proteins, immunofluorescence confocal microscopy, centrosome purification\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — yeast two-hybrid confirmed by Co-IP and co-localization, single lab\",\n      \"pmids\": [\"15705715\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"BIG2 localizes specifically (not BIG1) to recycling endosome structures during transferrin uptake and transferrin receptor (TfnR) recycling in COS7 cells. BIG2 siRNA knockdown causes perinuclear accumulation of TfnR and significantly slows transferrin release, demonstrating a functional role for BIG2 in TfnR recycling. BIG2 interacts with Exo70 in recycling endosome fractions.\",\n      \"method\": \"Immunofluorescence microscopy, density-gradient fractionation, siRNA knockdown, transferrin recycling assay\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — siRNA knockdown with functional trafficking readout, density-gradient fractionation, and localization; multiple orthogonal methods, replicated localization from prior study\",\n      \"pmids\": [\"16477018\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"BIG2 (but not BIG1) is required for trafficking of Filamin A (FLNA) from the Golgi apparatus to the cell membrane in neuroblastoma cells; transfection of dominant-negative ARFGEF2 partially blocks FLNA transport. BIG2 and FLNA are co-expressed in neural progenitors along the neuroependyma.\",\n      \"method\": \"Dominant-negative ARFGEF2 transfection, immunofluorescence for FLNA localization, Western blot co-expression\",\n      \"journal\": \"The Journal of comparative neurology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — dominant-negative functional assay with specific cargo (FLNA) readout, single lab\",\n      \"pmids\": [\"16320251\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"BIG2 (not BIG1) regulates constitutive release of TNFR1 exosome-like vesicles from human vascular endothelial cells via an ARF1- and ARF3-dependent mechanism. BIG2 co-localizes with TNFR1 in cytoplasmic vesicles, and this association is disrupted by BFA. ARF1 and ARF3 act nonredundantly and additively in TNFR1 exosome-like vesicle release.\",\n      \"method\": \"RNA interference (specific siRNA for BIG1, BIG2, ARF1, ARF3), TNFR1 release assay, immunofluorescence co-localization, BFA disruption\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — siRNA with functional release assay and mechanistic dissection of ARF isoforms, multiple orthogonal approaches, single lab but rigorous\",\n      \"pmids\": [\"17276987\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"PKA phosphorylates BIG2 in vitro, decreasing its GEP activity; this phosphorylation is reversed by protein phosphatase 1gamma (PP1gamma) but not PP1alpha or PP1beta. Endogenous PP1gamma (not PP1alpha or PP1beta) co-immunoprecipitates with BIG2 from microsomal fractions, establishing PP1gamma as a regulator of BIG2 activity.\",\n      \"method\": \"In vitro PKA phosphorylation assay, siRNA depletion of BIG2, immunoprecipitation GEP activity assay, recombinant phosphatase treatment, Co-IP of PP1 isoforms\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro kinase and phosphatase assays combined with endogenous Co-IP and siRNA depletion, multiple orthogonal methods in one study\",\n      \"pmids\": [\"17360629\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"AMY-1 (associate of Myc-1) co-immunoprecipitates with both BIG2 and BIG1 in vitro, but localizes to the TGN specifically through interaction with BIG2 (not BIG1) as demonstrated by RNAi: depletion of BIG2 (not BIG1) disperses AMY-1 from the TGN.\",\n      \"method\": \"Co-immunoprecipitation using FLAG-tagged AMY-1, siRNA knockdown of BIG1 or BIG2, immunofluorescence localization of AMY-1\",\n      \"journal\": \"Genes to cells : devoted to molecular & cellular mechanisms\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP combined with siRNA functional localization assay, single lab\",\n      \"pmids\": [\"16866877\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"BIG2 (and BIG1) form homodimers through interactions between their conserved DCB domains; within each homodimer, the DCB domain also interacts with the HUS domain. The HUS box is the most conserved motif in large ArfGEFs after the Sec7 domain and mediates the DCB/HUS interaction.\",\n      \"method\": \"Yeast two-hybrid assays, biochemical interaction assays, deletion mutant analysis, cellular dimerization assays in mammalian cells\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — yeast two-hybrid confirmed by biochemical assays and cellular dimerization assays, single lab with multiple methods\",\n      \"pmids\": [\"17640864\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Simultaneous knockdown of both BIG2 and BIG1 causes mislocalization of TGN/recycling endosome-associated proteins and blocks retrograde transport of furin from late endosomes to the TGN, a phenotype similar to depletion of AP-1, establishing BIG2 and BIG1 as redundant regulators of AP-1-dependent trafficking between TGN and endosomes.\",\n      \"method\": \"RNAi double knockdown, immunofluorescence localization of furin and TGN markers, comparison to AP-1 depletion\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — RNAi double knockdown with genetic epistasis comparison to AP-1 depletion, single lab\",\n      \"pmids\": [\"18417613\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"cAMP-induced release of TNFR1 exosome-like vesicles requires PKA activity and is mediated through BIG2's AKAP function: PKA regulatory subunit RIIbeta binds specifically to BIG2 AKAP domains B and C, and this interaction is required for both constitutive and cAMP-induced TNFR1 exosome-like vesicle release.\",\n      \"method\": \"siRNA knockdown of PKA regulatory subunits (RIIbeta), TNFR1 release assay, domain mapping of BIG2 AKAP sequences, 8-bromo-cAMP stimulation\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — siRNA with functional assay and domain mapping, single lab, builds directly on prior BIG2/TNFR1 study\",\n      \"pmids\": [\"18625701\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"Phosphodiesterase 3A (PDE3A) physically associates with BIG2 (and BIG1) complexes; specific depletion of PDE3A by siRNA or its inhibition by cilostamide significantly decreases membrane-associated BIG2 and BIG1 and reduces activated ARF1-GTP, linking PDE3A-dependent cAMP regulation within BIG2 AKAP complexes to ARF1 activation.\",\n      \"method\": \"siRNA depletion of PDE3A, PDE3A-specific inhibitor cilostamide, confocal immunofluorescence, ARF1-GTP measurement\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — siRNA and pharmacological inhibition with ARF activation readout, single lab\",\n      \"pmids\": [\"19332778\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Depletion of BIG2 (but not BIG1) by siRNA induces tubulation of the recycling endosomal compartment, while BIG1 depletion causes Golgi fragmentation into mini-stacks; this demonstrates non-redundant and distinct functions for BIG2 (recycling endosome integrity) vs. BIG1 (Golgi morphology).\",\n      \"method\": \"siRNA knockdown, fixed and live-cell fluorescence imaging of Golgi and endosomal markers\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — siRNA with live and fixed imaging, comparative study of BIG1 vs BIG2, single lab\",\n      \"pmids\": [\"20360857\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"The small G protein Arl1 is necessary and sufficient for Golgi recruitment of BIG2 (and BIG1) but not GBF1. Arl1 binds directly to the N-terminal region of Sec71 (the Drosophila ortholog of BIG1/BIG2), establishing Arl1 as the upstream recruiter that directs BIG2 specifically to the trans-Golgi.\",\n      \"method\": \"Liposome-based affinity purification to identify Arl1 effectors, Arl1 knockdown in mammalian cells, immunofluorescence of BIG1/BIG2/GBF1 Golgi localization\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — novel liposome-based affinity purification for direct binding combined with mammalian cell Arl1 knockdown functional localization, orthologous validation in Drosophila\",\n      \"pmids\": [\"22291037\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"BIG2 siRNA depletion causes perinuclear accumulation of integrin beta1 and delayed return to the cell surface, decreased cell motility, and reduced actin-based membrane protrusions; cytosolic levels of Arp2, Arp3, cofilin-1, phosphocofilin, vinculin, and Grb2 are increased, establishing BIG2 as a regulator of integrin beta1 recycling and actin dynamics in cell migration.\",\n      \"method\": \"siRNA knockdown, difference gel electrophoresis (DIGE) proteomics, immunofluorescence, wound-healing migration assay, integrin beta1 trafficking assay\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — siRNA with proteomics, migration assay, and integrin trafficking assay; single lab, multiple orthogonal readouts\",\n      \"pmids\": [\"22908276\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"GBF1-activated ARFs (ARF4 and ARF5, but not ARF3) facilitate BIG2 and BIG1 recruitment to the TGN, establishing a functional GEF cascade: GBF1 (pre-Golgi/Golgi/TGN) → ARF4/ARF5 activation → BIG1/BIG2 TGN recruitment → ARF activation for AP-1/GGA clathrin adaptor recruitment.\",\n      \"method\": \"GBF1 dominant-negative expression, ARF isoform-specific depletion, immunofluorescence of BIG1/BIG2 TGN localization, ultrastructural localization by immuno-EM\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — dominant-negative and ARF knockdown epistasis with ultrastructural validation, single lab\",\n      \"pmids\": [\"23386609\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"BIG2 physically associates (reciprocal Co-IP) with nonmuscle myosin IIA in HeLa cells independently of its ARF-GEF activity; depletion of BIG2 (or BIG1) enhances phosphorylation of myosin regulatory light chain (T18/S19) and increases F-actin content, impairing cell migration. BIG2 anchors a myosin phosphatase complex containing myosin IIA, protein phosphatase 1delta, and myosin phosphatase-targeting subunit 1 (MYPT1).\",\n      \"method\": \"Reciprocal Co-IP of endogenous proteins, siRNA depletion, phospho-myosin light chain measurement, F-actin quantification, Transwell cell migration assay, rescue by BIG2 C-terminal overexpression\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — reciprocal endogenous Co-IP, siRNA depletion, rescue experiments, multiple functional readouts (phosphorylation, F-actin, migration), single lab but comprehensive\",\n      \"pmids\": [\"23918382\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"BIG2 (and BIG1) physically interact with beta-catenin; depletion of BIG1/BIG2 or expression of GEF-inactive mutants causes perinuclear Golgi accumulation of beta-catenin and reduces PKA-phosphorylated beta-catenin (S675). BIG2 AKAP-C sequence is required for PKA-dependent S675 phosphorylation and beta-catenin transcription coactivator function, requiring both ARF-GEF activity and phospholipase D-dependent vesicular trafficking.\",\n      \"method\": \"Co-IP (BIG1/BIG2 antibodies), yeast two-hybrid, in vitro protein synthesis, siRNA depletion, GEF-inactive mutant expression, phospho-beta-catenin Western blot, transcription reporter assay\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — yeast two-hybrid confirmed by Co-IP and functional assays, single lab with multiple orthogonal methods\",\n      \"pmids\": [\"27162341\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"BIG2 co-localizes with the Golgi apparatus in hippocampal neurons and is required for Golgi deployment into major dendrites. BIG2 acts through ARF1 to activate RhoA and its downstream effector mDia1, forming a BIG2-ARF1-RhoA-mDia1 signaling axis that regulates dendritic Golgi polarization and dendrite growth/maintenance. In vivo, ARFGEF2 shRNA delivered by in utero electroporation impairs Golgi deployment into the apical dendrite.\",\n      \"method\": \"shRNA knockdown, constitutively active ARF1 Q71L rescue, RhoA activation assay, LPA treatment rescue, immunofluorescence, in utero electroporation in mouse embryos\",\n      \"journal\": \"Molecular neurobiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — shRNA with epistasis rescue experiments (ARF1 Q71L, RhoA activator), in vivo validation by in utero electroporation, single lab\",\n      \"pmids\": [\"29455446\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"BIG2 (and BIG1) knockdown significantly decreases VEGF mRNA and protein levels in glioblastoma U251 cells and HUVECs, and inhibits HUVEC angiogenesis by diminishing cell migration. Knockdown of the BIG2 homolog arfgef2 in zebrafish impairs angioblast migration and intersegmental vessel sprouting, and CRISPR/Cas9 deletion of arfgef2 causes vascular development defects, establishing a role for BIG2 in VEGF expression and angiogenesis beyond vesicular trafficking.\",\n      \"method\": \"siRNA knockdown, VEGF mRNA/protein quantification, HUVEC migration and angiogenesis assays, zebrafish morpholino knockdown and CRISPR/Cas9 deletion with vascular GFP imaging\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — siRNA and CRISPR/Cas9 in zebrafish with functional angiogenesis readouts, single lab with in vitro and in vivo validation\",\n      \"pmids\": [\"31199673\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"In Drosophila neuroblasts, Arf1 and its GEF ARFGEF2/Sec71 control asymmetric division by facilitating cortical localization of nonmuscle myosin II regulatory light chain (Sqh). Arf1 physically associates with Sqh and with Vibrator (a type I PITP), and Arf1/Sec71 facilitate PI(4)P localization to the neuroblast cortex, linking PI(4)P production to myosin II cortical anchoring during asymmetric division.\",\n      \"method\": \"Genetic epistasis in Drosophila, Co-immunoprecipitation of Arf1 with Sqh and Vibrator, immunofluorescence of PI(4)P and myosin II cortical localization, loss-of-function neuroblast division assays\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP combined with in vivo genetic epistasis in Drosophila, single study; ortholog of ARFGEF2 (Sec71) in a model organism\",\n      \"pmids\": [\"40208939\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"ARFGEF2/BIG2 is a large (~200 kDa) brefeldin A-sensitive guanine nucleotide exchange factor (GEF) for class I ARFs (ARF1 and ARF3) that localizes to the trans-Golgi network (TGN) and recycling endosomes, where it activates ARFs to recruit AP-1/GGA clathrin adaptors and maintain organelle integrity; it is recruited to the TGN by Arl1 (downstream of a GBF1→ARF4/5 cascade), functions as an A kinase-anchoring protein (AKAP) that coordinates PKA and PP1gamma signaling to regulate its own GEF activity, scaffolds myosin phosphatase complexes to control actomyosin dynamics and cell migration, regulates integrin beta1 and TNFR1 exosome-like vesicle recycling, modulates beta-catenin trafficking and transcriptional activity, and drives dendritic Golgi polarization via a BIG2-ARF1-RhoA-mDia1 axis in neurons.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"ARFGEF2 (BIG2) is a brefeldin A-sensitive guanine nucleotide exchange factor that activates class I ARFs (ARF1 and ARF3) to drive membrane trafficking at the trans-Golgi network (TGN) and recycling endosomes, and through this activity it controls cargo delivery, organelle integrity, and several downstream signaling outputs [#0, #3]. By activating ARFs at the TGN, BIG2 recruits the clathrin adaptors AP-1 and GGA — but not the COPI coat — placing it specifically in the TGN-to-endosome arm of membrane traffic, and it acts redundantly with its homolog BIG1 in AP-1-dependent retrograde transport while retaining a non-redundant role in maintaining recycling endosome integrity [#1, #2, #12, #15]. Its catalytic activity is required for recycling of cargoes including the transferrin receptor and integrin beta1, and for release of TNFR1 exosome-like vesicles, and BIG2 transports E-cadherin, beta-catenin, and Filamin A from the Golgi to the cell surface [#0, #3, #6, #7, #8, #17]. BIG2 is recruited to the TGN by the small G protein Arl1 acting downstream of a GBF1\\u2192ARF4/ARF5 cascade, and it homodimerizes through an intramolecular DCB/HUS interaction [#16, #18, #11]. Beyond catalysis, BIG2 functions as an A-kinase-anchoring protein (AKAP) with three N-terminal domains that bind PKA regulatory subunits; PKA phosphorylation lowers its GEF activity and is reversed by PP1gamma, and this AKAP/cAMP module — also engaging PDE3A — couples BIG2 to TNFR1 vesicle release and beta-catenin S675 phosphorylation and transcriptional coactivation [#4, #9, #13, #14, #20]. BIG2 additionally scaffolds a myosin phosphatase complex (myosin IIA, PP1delta, MYPT1) independently of its GEF activity to control myosin light-chain phosphorylation, F-actin content, and cell migration, and drives a BIG2-ARF1-RhoA-mDia1 axis governing dendritic Golgi polarization in neurons [#19, #21]. BIG2 is also required for VEGF expression and angiogenesis [#22].\",\n  \"teleology\": [\n    {\n      \"year\": 2002,\n      \"claim\": \"Established that BIG2 selectively controls the membrane association of the AP-1/GGA clathrin adaptors at the TGN rather than the COPI coat, defining which trafficking step it serves.\",\n      \"evidence\": \"BIG2 overexpression and dominant-negative mutant expression with immunofluorescence redistribution of ARF1, AP-1, GGA1, and COPI in cells\",\n      \"pmids\": [\"11777925\", \"12051703\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Did not establish direct catalytic GEF activity toward specific ARF isoforms\", \"Cargo specificity of the AP-1/GGA pathway not defined\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Showed BIG2-dependent TGN trafficking is needed for neural progenitor proliferation and for surface delivery of E-cadherin and beta-catenin, linking the GEF to a physiological/developmental output.\",\n      \"evidence\": \"Dominant-negative cDNA, brefeldin A inhibition, proliferation and immunolocalization assays in cultured cells\",\n      \"pmids\": [\"14647276\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not resolve direct vs indirect effect on cargo transport\", \"ARF isoform specificity not addressed\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Identified BIG2 as an AKAP with three mapped PKA-regulatory-subunit-binding domains whose membrane recruitment responds to cAMP, defining a non-catalytic scaffolding function.\",\n      \"evidence\": \"Yeast two-hybrid, reciprocal Co-IP of endogenous proteins, 28 deletion mutants, subcellular fractionation with cAMP elevation\",\n      \"pmids\": [\"12571360\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not show how PKA anchoring feeds back on GEF activity\", \"Functional consequence of cAMP-induced translocation not established\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Defined BIG2 catalytic specificity toward class I ARFs (ARF1/ARF3) and demonstrated via active-site mutagenesis and ARF epistasis that it maintains recycling endosome integrity.\",\n      \"evidence\": \"Catalytically inactive E738K mutant, ARF1/ARF3 inactivation epistasis, localization in cells\",\n      \"pmids\": [\"15385626\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism distinguishing TGN vs recycling endosome pools not resolved\", \"Recruitment determinants to each compartment not defined\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Linked BIG2 to the exocyst by identifying an N-terminal Exo70 interaction and shared TGN/centrosomal localization, extending its reach toward plasma-membrane-directed traffic.\",\n      \"evidence\": \"Yeast two-hybrid, Co-IP of in vitro translated proteins, confocal microscopy, centrosome purification in HepG2 cells\",\n      \"pmids\": [\"15705715\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional consequence of Exo70 binding not tested\", \"Endogenous interaction not confirmed in this study\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Demonstrated a non-redundant, BIG2-specific role (distinct from BIG1) in transferrin receptor recycling and in trafficking the cytoskeletal cargo Filamin A, plus TGN anchoring of AMY-1.\",\n      \"evidence\": \"siRNA knockdown with transferrin recycling assay and density-gradient fractionation; dominant-negative FLNA trafficking assay; reciprocal Co-IP and RNAi for AMY-1 localization\",\n      \"pmids\": [\"16477018\", \"16320251\", \"16866877\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular basis for BIG2 vs BIG1 cargo discrimination unresolved\", \"Direct GEF-cargo coupling not established\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Connected BIG2 GEF activity to a secretory output (TNFR1 exosome-like vesicle release) via nonredundant ARF1/ARF3 action, and established the PKA/PP1gamma phosphoregulatory loop controlling BIG2 catalysis.\",\n      \"evidence\": \"Isoform-specific siRNA with TNFR1 release assay and BFA disruption; in vitro PKA phosphorylation/GEP activity assay, recombinant PP1 isoform treatment, endogenous Co-IP\",\n      \"pmids\": [\"17276987\", \"17360629\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"In vivo relevance of PKA/PP1gamma regulation not shown\", \"Site of phosphorylation on BIG2 not mapped\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Defined the structural basis of BIG2 self-association through DCB-mediated homodimerization and an intramolecular DCB/HUS interaction.\",\n      \"evidence\": \"Yeast two-hybrid, biochemical interaction and deletion-mutant analysis, cellular dimerization assays\",\n      \"pmids\": [\"17640864\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model of the dimer\", \"Functional requirement of dimerization for GEF activity untested\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Established BIG2/BIG1 redundancy in AP-1-dependent retrograde furin transport and showed cAMP-induced TNFR1 vesicle release operates through BIG2 AKAP domains binding RIIbeta.\",\n      \"evidence\": \"RNAi double knockdown with furin localization vs AP-1 depletion comparison; PKA subunit siRNA, TNFR1 release assay, AKAP domain mapping\",\n      \"pmids\": [\"18417613\", \"18625701\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Degree of redundancy across cargoes not generalized\", \"Mechanism coupling AKAP-bound PKA to ARF activation incomplete\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Placed PDE3A within BIG2 AKAP complexes as a cAMP-degrading regulator required for membrane association of BIG2 and ARF1 activation.\",\n      \"evidence\": \"PDE3A siRNA and cilostamide inhibition, confocal microscopy, ARF1-GTP measurement\",\n      \"pmids\": [\"19332778\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct vs indirect PDE3A-BIG2 interaction not resolved\", \"Cargo-level consequences not measured\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Distinguished non-redundant morphological roles: BIG2 depletion tubulates recycling endosomes while BIG1 depletion fragments the Golgi.\",\n      \"evidence\": \"siRNA knockdown with fixed and live-cell imaging of Golgi and endosomal markers\",\n      \"pmids\": [\"20360857\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular determinants of compartment-specific action unknown\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Identified Arl1 as the upstream small G protein necessary and sufficient to recruit BIG2 to the TGN, defining how the GEF is targeted to its compartment.\",\n      \"evidence\": \"Liposome-based affinity purification, Arl1 knockdown in mammalian cells, Drosophila Sec71 ortholog binding, immunofluorescence\",\n      \"pmids\": [\"22291037\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How Arl1 recruitment is itself initiated unresolved at this step\", \"Recycling endosome recruitment mechanism not addressed\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Extended BIG2's recycling function to integrin beta1 and linked it to actin dynamics and cell motility through proteomic and migration readouts.\",\n      \"evidence\": \"siRNA knockdown, DIGE proteomics, integrin beta1 trafficking and wound-healing migration assays\",\n      \"pmids\": [\"22908276\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct mechanism connecting integrin recycling to actin regulators not defined\", \"GEF dependence of the migration phenotype not isolated\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Positioned BIG2 in a GEF cascade (GBF1\\u2192ARF4/ARF5\\u2192BIG2 recruitment) and revealed a GEF-independent scaffolding role anchoring a myosin phosphatase complex that controls actomyosin and migration.\",\n      \"evidence\": \"GBF1 dominant-negative and ARF-isoform depletion with immuno-EM; reciprocal endogenous Co-IP of myosin IIA, siRNA, phospho-MLC and F-actin assays, Transwell migration, C-terminal rescue\",\n      \"pmids\": [\"23386609\", \"23918382\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How catalytic and scaffolding functions are coordinated within one molecule unclear\", \"Structural basis of myosin phosphatase anchoring not defined\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Connected BIG2 trafficking and AKAP function to beta-catenin biology, showing it controls beta-catenin Golgi exit, PKA-dependent S675 phosphorylation, and transcriptional coactivation.\",\n      \"evidence\": \"Co-IP, yeast two-hybrid, siRNA, GEF-inactive mutants, phospho-beta-catenin Western blot, transcription reporter assays\",\n      \"pmids\": [\"27162341\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct vs trafficking-mediated effect on beta-catenin phosphorylation not fully separated\", \"Target gene specificity not mapped\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Defined a neuronal BIG2-ARF1-RhoA-mDia1 axis required for dendritic Golgi polarization and dendrite growth, validated in vivo.\",\n      \"evidence\": \"shRNA knockdown, ARF1 Q71L and LPA rescue, RhoA activation assay, immunofluorescence, in utero electroporation in mouse\",\n      \"pmids\": [\"29455446\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"How ARF1 activates RhoA mechanistically not resolved\", \"Behavioral/developmental consequences not assessed\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Revealed a role for BIG2 in VEGF expression and angiogenesis, extending its function beyond intracellular trafficking, with in vivo zebrafish validation.\",\n      \"evidence\": \"siRNA, VEGF mRNA/protein quantification, HUVEC migration/angiogenesis assays, zebrafish morpholino and CRISPR/Cas9 deletion with vascular imaging\",\n      \"pmids\": [\"31199673\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism linking BIG2 to VEGF transcription not defined\", \"Whether the angiogenesis role is GEF-dependent unclear\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Showed in a Drosophila ortholog context that Arf1/Sec71 anchor cortical myosin II during asymmetric neuroblast division by directing PI(4)P localization, linking lipid production to actomyosin organization.\",\n      \"evidence\": \"Drosophila genetic epistasis, Co-IP of Arf1 with Sqh and Vibrator, PI(4)P and myosin II cortical imaging, loss-of-function division assays\",\n      \"pmids\": [\"40208939\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Conservation of the PI(4)P-myosin mechanism in mammalian ARFGEF2 not tested\", \"Direct ARFGEF2 (vs Arf1) requirement in this lipid pathway not isolated\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How BIG2 integrates its catalytic ARF-GEF activity, AKAP/cAMP phosphoregulation, and GEF-independent myosin phosphatase scaffolding into a single coordinated program across distinct compartments and cell types remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No integrated structural model of full-length BIG2 with its partners\", \"Mechanism switching BIG2 between catalytic and scaffolding modes unknown\", \"In vivo relevance of most regulatory loops not established in mammals\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [3, 1, 16]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [4, 19, 9]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005802\", \"supporting_discovery_ids\": [0, 1, 3, 16]},\n      {\"term_id\": \"GO:0005768\", \"supporting_discovery_ids\": [3, 6, 15]},\n      {\"term_id\": \"GO:0005815\", \"supporting_discovery_ids\": [5]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [4]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-5653656\", \"supporting_discovery_ids\": [0, 1, 2, 6, 12]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [9, 20, 21]},\n      {\"term_id\": \"R-HSA-9609507\", \"supporting_discovery_ids\": [3, 7, 8, 17]}\n    ],\n    \"complexes\": [\n      \"myosin phosphatase complex (myosin IIA / PP1delta / MYPT1)\",\n      \"BIG2 AKAP-PKA complex\"\n    ],\n    \"partners\": [\n      \"ARF1\",\n      \"ARF3\",\n      \"Arl1\",\n      \"Exo70\",\n      \"MYH9 (nonmuscle myosin IIA)\",\n      \"PPP1CC (PP1gamma)\",\n      \"PDE3A\",\n      \"CTNNB1 (beta-catenin)\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}