{"gene":"ARAP1","run_date":"2026-06-09T22:02:44","timeline":{"discoveries":[{"year":2002,"finding":"ARAP1 has PIP3-dependent Arf GAP activity and Rho GAP activity in vitro. Its Rho GAP activity mediates cell rounding and loss of stress fibers when overexpressed. Its Arf GAP activity mediates changes in the Golgi apparatus and formation of filopodia via increased cellular Cdc42 activity. Both activities contribute to inhibiting cell spreading. ARAP1 associates with the Golgi.","method":"In vitro GAP assays, overexpression in cells, immunofluorescence/localization studies","journal":"Molecular cell","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — in vitro enzymatic assays combined with cell biological readouts and mutagenesis-level domain dissection, founding paper replicated by subsequent studies","pmids":["11804590"],"is_preprint":false},{"year":2003,"finding":"ARAP1 (the 493-aa isoform identified in this study, distinct from the multi-domain ARAP1) binds the carboxyl terminus of the AT1A angiotensin II receptor via yeast two-hybrid and co-immunoprecipitation, co-localizes with recycled AT1A at the plasma membrane, and promotes recycling of AT1A to the plasma membrane in HEK-293 cells, restoring Ca2+ release response to a second Ang II stimulation.","method":"Yeast two-hybrid, co-immunoprecipitation, immunocytochemistry, functional Ca2+ release assay","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2–3 / Moderate — reciprocal Co-IP and functional assay in single lab; the identified protein is a shorter isoform but same gene locus","pmids":["14559250"],"is_preprint":false},{"year":2008,"finding":"ARAP1 rapidly and transiently associates with the cell edge and with Rab5/rabaptin-5/EGFR-positive punctate structures that precede EEA1-positive early endosomes after EGF treatment. Recruitment requires active Rab5 and an EGFR-derived signal. siRNA knockdown of ARAP1 accelerates association of EGF with EEA1 endosomes, accelerates EGFR degradation, and diminishes/shortens ERK and JNK phosphorylation, demonstrating that ARAP1 retards early endocytic trafficking of EGFR and prolongs downstream signaling.","method":"siRNA knockdown, live-cell imaging, immunofluorescence colocalization, western blot for ERK/JNK phosphorylation","journal":"Traffic (Copenhagen, Denmark)","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean RNAi with defined trafficking and signaling phenotypes, replicated independently in a companion paper (PMID 18764928)","pmids":["18939958"],"is_preprint":false},{"year":2008,"finding":"ARAP1 localizes to the Golgi complex and to internal membranes of multivesicular bodies/late endosomes. Its distribution is controlled by phosphorylation and by binding to 3- and 4-phosphorylated phosphoinositides through its PH domains. ARAP1 knockdown causes EGFR accumulation in sorting/late endosomal compartments and inhibits EGFR degradation, resulting in prolonged EGF signaling, placing ARAP1 at a late step of EGFR endocytic trafficking.","method":"siRNA knockdown, immunofluorescence, subcellular fractionation, western blot","journal":"Traffic (Copenhagen, Denmark)","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean KD with defined compartment-specific phenotype, independently replicated by Yoon et al. 2008 (PMID 18939958)","pmids":["18764928"],"is_preprint":false},{"year":2009,"finding":"The first PH domain (PH1) of ARAP1 specifically binds PtdIns(3,4,5)P3 with ~1.6 µM affinity. PH1 does not mediate PtdIns(3,4,5)P3-dependent recruitment of ARAP1 to membranes in cells; instead, PtdIns(3,4,5)P3 binding to PH1 allosterically stimulates Arf GAP catalytic activity and is required for ARAP1's in vivo function in regulating EGFR endocytic trafficking.","method":"In vitro lipid-binding assay, in vitro Arf GAP activity assay, live-cell imaging, site-directed mutagenesis, EGFR trafficking assay","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution with mutagenesis plus in vivo trafficking readout, single lab with multiple orthogonal methods","pmids":["19666464"],"is_preprint":false},{"year":2010,"finding":"PTK6 (Brk) associates with ARAP1 in an EGF/EGFR-dependent manner via its SH2 domain (requiring Arg105). PTK6 phosphorylates ARAP1 at Tyr231. Phosphorylation of ARAP1 at Y231 is required for ARAP1 to inhibit EGFR down-regulation; the Y231F mutant fails to do so. Silencing PTK6 in breast carcinoma cells decreases EGFR levels, placing ARAP1 phosphorylation by PTK6 as a mechanism that sustains EGFR signaling.","method":"Co-immunoprecipitation (Flag-PTK6 pull-down, MALDI-TOF MS identification of ARAP1), in vitro kinase assay, site-directed mutagenesis (Y231F), EGFR down-regulation assay, PTK6 siRNA","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1–2 / Moderate — kinase assay, mutagenesis, and functional EGFR trafficking readout in single lab with multiple orthogonal methods","pmids":["20554524"],"is_preprint":false},{"year":2011,"finding":"ARAP1 associates with CIN85 via its PXPXXRX motif (requiring Arg86 and Arg90) interacting with CIN85 SH3 domains. A CIN85-binding-deficient ARAP1 mutant fails to rescue the effect of ARAP1 knockdown on EGFR trafficking to the early endosome. Overexpression of ARAP1 reduces Cbl-mediated ubiquitination of EGFR and slows Cbl-dependent EGFR degradation, with ARAP1 proposed to compete with Cbl for CIN85 binding to divert EGFR away from the early endosome/lysosome degradation pathway.","method":"Co-immunoprecipitation, site-directed mutagenesis, siRNA knockdown of CIN85/ARAP1, EGFR ubiquitination assay, EGFR degradation assay","journal":"Biology of the cell","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP, mutagenesis, and multiple functional assays in single lab","pmids":["21275903"],"is_preprint":false},{"year":2012,"finding":"Growth factor stimulation induces localization of ARAP1 to the plasma membrane inside the ring structure of circular dorsal ruffles (CDRs). ARAP1 overexpression increases CDR ring size in an Arf GAP activity-dependent manner, while ARAP1 knockdown produces smaller CDRs. Expression of dominant-negative Arf1 or Arf5 (the substrates of ARAP1) also expands CDR size, placing Arf1 and Arf5 downstream of ARAP1 in CDR ring-size control.","method":"Fluorescence microscopy, ARAP1 overexpression, siRNA knockdown, dominant-negative Arf1/Arf5, Arf GAP-dead mutant","journal":"Molecular biology of the cell","confidence":"High","confidence_rationale":"Tier 2 / Moderate — genetic epistasis with dominant-negative Arfs plus GAP-dead mutant, clean KD phenotype, single lab with multiple orthogonal approaches","pmids":["22573888"],"is_preprint":false},{"year":2008,"finding":"ARAP1 interacts with the intracellular portion of TRAIL death receptor DR4 (identified by yeast two-hybrid), co-precipitates with DR4, and co-localizes with it in the ER/Golgi, plasma membrane, and early endosomes of TRAIL-treated cells. ARAP1 knockdown significantly reduces DR4 surface localization in multiple tumor cell lines and slows TRAIL-induced cell death, implicating ARAP1 in DR4 trafficking to the cell surface.","method":"Yeast two-hybrid, co-immunoprecipitation, immunofluorescence colocalization, siRNA knockdown, flow cytometry (surface DR4), cell death assay","journal":"Apoptosis : an international journal on programmed cell death","confidence":"Medium","confidence_rationale":"Tier 2–3 / Moderate — yeast two-hybrid corroborated by Co-IP and functional siRNA data, single lab","pmids":["18165900"],"is_preprint":false},{"year":2018,"finding":"In osteoclasts, ARAP1 is part of a protein complex at podosomes/sealing zones where its RhoGAP domain regulates actin dynamics. At endosomes, ARAP1 interacts with AP-3 adaptor complexes where its Arf GAP domain regulates Arf1-dependent AP-3 binding to membranes and lysosomal membrane protein transport to ruffled borders. ARAP1 or AP-3 depletion in osteoclasts impairs their capacity to digest bone in vitro.","method":"Co-immunoprecipitation, immunofluorescence, siRNA knockdown, bone resorption assay in vitro, domain-specific mutant analysis","journal":"iScience","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP and functional bone-resorption assay with domain dissection, single lab","pmids":["30240610"],"is_preprint":false},{"year":2018,"finding":"The ARAP1 PXPXXRX(except P)XXR/H/K motif binds the CIN85 SH3B domain with high affinity and specificity. Crystal/biochemical structure shows that the β2–β3 loops of CIN85 SH3 domains and the H87(ARAP1)/E132(CIN85) interaction are critical for binding specificity. ARAP1 competes with Cbl for CIN85 binding as demonstrated by competitive analytical gel-filtration chromatography and isothermal titration calorimetry.","method":"Biochemical binding assays, structural (domain-swap analysis, structure alignment), isothermal titration calorimetry (ITC), analytical gel-filtration chromatography","journal":"Biochemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — structural and thermodynamic characterization with ITC, competitive binding assay, multiple orthogonal biophysical methods in single study","pmids":["29589748"],"is_preprint":false},{"year":2013,"finding":"Arap1-deficient mice show accelerated sepsis-induced hypotension and reduced vascular sensitivity to angiotensin II (measured in isolated perfused kidney), confirming that Arap1 is required for normal AT1 receptor-dependent vasoconstriction. During endotoxemia, Arap1 expression is successively down-regulated in wildtype mice (to <10% baseline), and this down-regulation can be recapitulated in cultured mesangial cells by TNFα and IFNγ.","method":"Arap1 knockout mice, telemetry blood pressure measurement, isolated perfused kidney assay, LPS-induced endotoxemia model, cytokine treatment of cultured cells","journal":"Critical care (London, England)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic KO with defined vascular phenotype and in vitro mechanistic follow-up, single lab","pmids":["23844607"],"is_preprint":false},{"year":2006,"finding":"Proximal-tubule-specific overexpression of ARAP1 in transgenic mice causes hypertension (~20–25 mmHg increase in systolic BP), decreased urine volume, and kidney hypertrophy. The hypertension is completely normalized by renin-angiotensin system inhibition and prevented by low-salt diet, placing renal ARAP1 in regulation of BP via the intrarenal renin-angiotensin system.","method":"Transgenic mouse overexpression (proximal tubule-specific), telemetry/tail-cuff BP measurement, pharmacological RAS inhibition, dietary salt manipulation","journal":"Hypertension (Dallas, Tex. : 1979)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo transgenic model with pharmacological rescue, single lab","pmids":["16801480"],"is_preprint":false},{"year":2012,"finding":"In vivo, Arap1 protein is restricted to the renal vasculature and glomerular mesangial cells (absent from tubular epithelia). Angiotensin II infusion suppresses renal Arap1 mRNA and protein, while AT1 antagonism (losartan) increases Arap1 expression. Angiotensin II also suppresses Arap1 in cultured mesangial cells in a time- and dose-dependent manner, establishing a negative feedback loop between Ang II signaling and Arap1 expression.","method":"Immunohistochemistry (localization in mouse and human kidneys), in vivo Ang II infusion, losartan treatment, renal artery stenosis, water restriction models; western blot and RT-PCR of Arap1","journal":"American journal of physiology. Renal physiology","confidence":"Medium","confidence_rationale":"Tier 2–3 / Moderate — direct localization by IHC with functional regulation confirmed by multiple in vivo manipulations, single lab","pmids":["22357923"],"is_preprint":false},{"year":2017,"finding":"Arap1 knockout mice develop photoreceptor degeneration starting at 4 weeks postnatal. Immunohistochemistry detects Arap1 predominantly in Müller glia (not photoreceptors), implicating a non-cell-autonomous Müller glia-dependent mechanism for photoreceptor survival.","method":"Germline Arap1 knockout mice (KOMP2), optical coherence tomography, fundus photography, immunohistochemistry, electroretinography","journal":"Investigative ophthalmology & visual science","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — clean KO phenotype with localization data, but mechanism not fully defined; single lab/screen","pmids":["28324111"],"is_preprint":false},{"year":2022,"finding":"Conditional knockout of Arap1 in RPE (Vmd2-Cre) but not Müller glia (Glast-Cre) recapitulates the photoreceptor degeneration of germline Arap1-/- mice. Arap1-/- mice show a clear phagocytic defect in RPE outer segment phagocytosis in vivo. Mass spectrometry of ARAP1 co-immunoprecipitation identifies candidate interactors involved in phagocytosis, cytoskeletal organization, intracellular trafficking and endocytosis, establishing that ARAP1 expression in RPE is required for photoreceptor survival via its role in RPE phagocytosis.","method":"Conditional (cell-type-specific) Arap1 knockout mice, in vivo outer segment phagocytosis quantification, mass spectrometry of ARAP1 co-IP","journal":"Disease models & mechanisms","confidence":"High","confidence_rationale":"Tier 2 / Moderate — cell-type-specific KO with defined cellular phenotype (phagocytosis assay) and MS interactome, single lab with multiple orthogonal approaches","pmids":["35758026"],"is_preprint":false},{"year":2020,"finding":"ARAP1 maintains persistent EGFR activation in high-glucose-treated renal tubular cells by reducing EGFR ubiquitination through competing with Cbl for CIN85 binding, as shown by co-immunoprecipitation and ubiquitination assays. The lncRNA ARAP1-AS2 directly interacts with ARAP1 (RNA pulldown), and overexpression of ARAP1-AS2 promotes this EGFR/TGF-β/Smad3 signaling.","method":"Co-immunoprecipitation, ubiquitination assay, RNA pulldown, dual-immunofluorescence, siRNA knockdown/overexpression","journal":"Journal of cellular and molecular medicine","confidence":"Medium","confidence_rationale":"Tier 2–3 / Moderate — Co-IP and ubiquitination assay corroborate the CIN85-competition model from PMID 21275903, single lab","pmids":["32969198"],"is_preprint":false},{"year":2023,"finding":"ARAP1 overexpression significantly inhibits migration and invasion of lung adenocarcinoma cells in vitro and in vivo, and this effect depends on its RhoGAP activity; the mechanism is suppression of Rho signaling leading to inhibition of stress fiber formation.","method":"Overexpression of wild-type vs. RhoGAP-dead ARAP1 mutant, transwell migration/invasion assays, mouse metastasis model, F-actin staining","journal":"Discover oncology","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — domain-specific mutant with functional phenotype, single lab, single study","pmids":["38008882"],"is_preprint":false},{"year":2015,"finding":"ARAP1 knockdown in high-glucose-treated HK-2 renal tubular cells decreases Cdc42-GTP levels and reduces cytoskeleton reorganization, cell viability, migration, and EMT/fibrosis marker expression, placing ARAP1 upstream of Cdc42 activation in this cellular context.","method":"siRNA knockdown of ARAP1, Cdc42-GTP pull-down (CRIB assay), cell migration assay, western blot for EMT markers","journal":"Journal of cellular physiology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single KD experiment with downstream Cdc42-GTP measurement, single lab","pmids":["31975379"],"is_preprint":false},{"year":2025,"finding":"ARAP1 is transiently recruited to cell protrusions following chemokine stimulation in lymphocytes. Its Ras-association (RA) domain binds Rap1 and Rac1, and this binding is required for ARAP1-mediated RhoA inhibition. ARAP1-deficient cells show enhanced chemokine-directed migration with increased RhoA activation and F-actin polymerization. ARAP1 overexpression inhibits migration in a RhoGAP domain-dependent manner.","method":"ARAP1 knockout cells, FRET-based RhoA biosensor, Rap1/Rac1 pulldown/binding assay, live-cell imaging of ARAP1 localization, domain-mutant overexpression, migration assay","journal":"Frontiers in immunology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic KO with FRET biosensor readout and domain-specific rescue/mutant analysis, single lab with multiple orthogonal methods","pmids":["41488654"],"is_preprint":false},{"year":2025,"finding":"In Hep3B hepatocellular carcinoma cells, ARAP1 localizes to circular dorsal ruffles (CDRs) and to mitochondria (not seen in control HCC lines). ARAP1 KO reduces CDR size, disrupts lamellipodia within CDRs, attenuates extracellular solute uptake (macropinocytosis), and reduces cell growth and malignant potential. ARAP1 is actively degraded via the proteasome in Hep3B cells (MG132 restores levels), and mitochondrial dysfunction (CCCP) blocks CDRs, linking mitochondrial activity to ARAP1-dependent CDR formation.","method":"ARAP1 CRISPR knockout, confocal microscopy, scanning electron microscopy, macropinocytosis uptake assay, proteasome inhibitor (MG132), mitochondrial inhibitor (CCCP), ARF1 inhibitor (Golgicide A), cell proliferation/invasion assays","journal":"Cell communication and signaling : CCS","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — CRISPR KO with multiple cell-biological readouts and pharmacological perturbations, single lab","pmids":["39934854"],"is_preprint":false}],"current_model":"ARAP1 is a PtdIns(3,4,5)P3-dependent dual GTPase-activating protein (Arf GAP and Rho GAP) that localizes to the Golgi, endosomes, and cell protrusions, where it acts as a signaling hub: its Arf GAP activity (stimulated allosterically by PIP3 binding to PH1 and directed at Arf1/Arf5) controls circular dorsal ruffle size, AP-3-dependent lysosomal trafficking in osteoclasts, and the early-to-late endosomal transit of EGFR, while its Rho GAP activity suppresses RhoA-driven actin stress fiber formation and cell migration; PTK6 phosphorylates ARAP1 at Tyr231 to enhance EGFR retention, and ARAP1 competes with Cbl for CIN85 SH3B binding (structurally defined) to reduce EGFR ubiquitination and slow receptor degradation; ARAP1 also traffics DR4 and AT1 receptors to the plasma membrane and, in retinal pigment epithelium, is required for outer-segment phagocytosis and photoreceptor survival."},"narrative":{"mechanistic_narrative":"ARAP1 is a phosphoinositide-regulated dual GTPase-activating protein that integrates membrane lipid signals with Arf and Rho family GTPase output to control membrane trafficking and actin-dependent cell-surface dynamics [PMID:11804590]. It carries both an Arf GAP and a Rho GAP activity: PtdIns(3,4,5)P3 binding to its first PH domain allosterically stimulates the Arf GAP catalytic activity that acts on Arf1 and Arf5, while the Rho GAP activity drives loss of stress fibers and inhibits cell spreading [PMID:11804590, PMID:19666464, PMID:22573888]. Through these activities ARAP1 localizes to the Golgi and to late endosomal/multivesicular compartments and governs growth-factor receptor trafficking: it is recruited in a Rab5- and EGFR-dependent manner to early endocytic structures and retards the transit of EGFR into degradative compartments, thereby prolonging downstream ERK/JNK signaling [PMID:18939958, PMID:18764928]. ARAP1 slows EGFR degradation by binding the adaptor CIN85 through a proline-arginine motif and competing with Cbl for the CIN85 SH3B domain, reducing EGFR ubiquitination — an interaction defined structurally and thermodynamically [PMID:21275903, PMID:29589748]; PTK6 phosphorylates ARAP1 at Tyr231 to reinforce EGFR retention [PMID:20554524]. The Arf GAP activity also sets the size of growth-factor-induced circular dorsal ruffles downstream of Arf1/Arf5 and supports macropinocytosis [PMID:22573888, PMID:39934854], and ARAP1 directs surface delivery of the death receptor DR4 and the AT1 angiotensin II receptor [PMID:18165900, PMID:14559250]. The Rho GAP activity, dependent on Rap1/Rac1 binding through the Ras-association domain, suppresses RhoA-driven actin polymerization and cell migration in lymphocytes and tumor cells [PMID:38008882, PMID:41488654]. In vivo, ARAP1 functions in osteoclast bone resorption via AP-3-dependent lysosomal protein transport [PMID:30240610], in renal vascular angiotensin II responsiveness and blood-pressure control [PMID:23844607, PMID:16801480], and in retinal pigment epithelium, where it is required for outer-segment phagocytosis and photoreceptor survival [PMID:35758026].","teleology":[{"year":2002,"claim":"Established ARAP1 as a bifunctional PIP3-dependent Arf GAP and Rho GAP that couples phosphoinositide signaling to both Golgi/filopodial dynamics and stress-fiber loss, defining its core enzymatic identity.","evidence":"In vitro GAP assays plus overexpression and localization studies in cells","pmids":["11804590"],"confidence":"High","gaps":["Did not define the physiological substrate Arf isoforms in vivo","Mechanism of PIP3 dependence not yet resolved at the domain level"]},{"year":2003,"claim":"Linked an ARAP1 isoform to G-protein-coupled receptor recycling, showing it promotes AT1A angiotensin receptor return to the plasma membrane to restore signaling competence.","evidence":"Yeast two-hybrid, reciprocal Co-IP, immunocytochemistry, and Ca2+ release assay in HEK-293 cells","pmids":["14559250"],"confidence":"Medium","gaps":["Used a short 493-aa isoform distinct from full-length ARAP1","GAP-domain involvement in recycling not tested"]},{"year":2008,"claim":"Resolved ARAP1's role in EGFR trafficking from both ends of the endocytic route, showing it is recruited to early Rab5/EGFR structures and retards transit to EEA1 endosomes while also acting at late sorting/MVB compartments to slow receptor degradation and prolong signaling.","evidence":"siRNA knockdown, live-cell imaging, colocalization, subcellular fractionation, and ERK/JNK phospho-blots (two companion studies)","pmids":["18939958","18764928"],"confidence":"High","gaps":["Did not identify the molecular tether retaining EGFR","Relative contribution of early vs late steps unresolved"]},{"year":2008,"claim":"Extended ARAP1's trafficking function to death-receptor delivery, implicating it in routing DR4 to the cell surface to enable TRAIL-induced apoptosis.","evidence":"Yeast two-hybrid, Co-IP, colocalization, siRNA, surface flow cytometry, and cell-death assays in tumor lines","pmids":["18165900"],"confidence":"Medium","gaps":["GAP-domain dependence not dissected","Single-lab interaction without structural detail"]},{"year":2009,"claim":"Defined the mechanism of phosphoinositide control, showing PH1 binds PtdIns(3,4,5)P3 not to recruit ARAP1 but to allosterically stimulate its Arf GAP catalysis, which is required for EGFR trafficking function.","evidence":"In vitro lipid-binding and Arf GAP assays, mutagenesis, and EGFR trafficking readouts","pmids":["19666464"],"confidence":"High","gaps":["Membrane recruitment mechanism left unexplained","Structural basis of allostery not solved"]},{"year":2010,"claim":"Identified an upstream regulatory input, showing PTK6 binds and phosphorylates ARAP1 at Tyr231 to enforce EGFR retention and sustain receptor signaling.","evidence":"Co-IP/MS, in vitro kinase assay, Y231F mutagenesis, and EGFR down-regulation and PTK6 siRNA assays","pmids":["20554524"],"confidence":"High","gaps":["How Y231 phosphorylation alters ARAP1 activity is unknown","Crosstalk with PIP3 regulation untested"]},{"year":2011,"claim":"Established the adaptor mechanism by which ARAP1 slows EGFR degradation, showing it binds CIN85 via a PXPXXRX motif and competes with Cbl to reduce EGFR ubiquitination and divert it from the degradative pathway.","evidence":"Co-IP, mutagenesis, CIN85/ARAP1 siRNA, ubiquitination and degradation assays","pmids":["21275903"],"confidence":"High","gaps":["Competition shown functionally but not yet structurally","Did not measure binding affinities"]},{"year":2012,"claim":"Placed Arf1/Arf5 as direct effectors of ARAP1 in actin remodeling, demonstrating that ARAP1 Arf GAP activity sets circular dorsal ruffle ring size.","evidence":"Microscopy with overexpression, knockdown, dominant-negative Arf1/Arf5, and GAP-dead mutant epistasis","pmids":["22573888"],"confidence":"High","gaps":["Functional purpose of CDR size control not established","Link to receptor internalization untested"]},{"year":2012,"claim":"Located endogenous ARAP1 to renal vasculature/mesangium and revealed a negative feedback loop in which angiotensin II suppresses ARAP1 expression and AT1 blockade raises it.","evidence":"IHC localization with in vivo Ang II infusion, losartan, and mesangial cell culture","pmids":["22357923"],"confidence":"Medium","gaps":["Molecular mechanism of transcriptional suppression unknown","Connection to AT1 trafficking not directly demonstrated in vivo"]},{"year":2013,"claim":"Provided genetic evidence that ARAP1 is required for AT1-dependent vasoconstriction, with knockout mice showing impaired angiotensin II vascular sensitivity and worsened sepsis-induced hypotension.","evidence":"Arap1 knockout mice, telemetry, isolated perfused kidney, LPS endotoxemia, and cytokine treatment of cells","pmids":["23844607"],"confidence":"Medium","gaps":["Did not pinpoint the cellular site of action","Mechanistic link to AT1 receptor trafficking inferred not proven"]},{"year":2006,"claim":"Showed renal ARAP1 controls blood pressure, with proximal-tubule overexpression causing RAS-dependent, salt-sensitive hypertension.","evidence":"Proximal-tubule-specific transgenic mice with BP telemetry, RAS inhibition, and dietary salt manipulation","pmids":["16801480"],"confidence":"Medium","gaps":["Molecular mechanism downstream of ARAP1 overexpression unresolved","Cell-autonomous tubular pathway not defined"]},{"year":2018,"claim":"Solved the structural and thermodynamic basis of the ARAP1–CIN85 interaction, mapping the SH3B-binding motif and confirming direct competition with Cbl by ITC and gel filtration.","evidence":"Structural domain-swap analysis, ITC, and competitive analytical gel-filtration chromatography","pmids":["29589748"],"confidence":"High","gaps":["Did not test the structural model in cellular EGFR trafficking","In vivo stoichiometry with Cbl unknown"]},{"year":2018,"claim":"Extended ARAP1's dual-GAP logic to osteoclast bone resorption, with the RhoGAP domain acting at podosomes and the Arf GAP domain governing Arf1-dependent AP-3 recruitment for lysosomal protein transport.","evidence":"Co-IP, immunofluorescence, siRNA, domain-mutant analysis, and in vitro bone resorption assay","pmids":["30240610"],"confidence":"Medium","gaps":["Single-lab interactome","How the two GAP activities are spatially coordinated is unclear"]},{"year":2017,"claim":"Implicated ARAP1 in photoreceptor survival, with knockout mice degenerating and initial localization pointing to a non-cell-autonomous Müller glia mechanism.","evidence":"Germline Arap1 knockout mice with OCT, fundus imaging, IHC, and ERG","pmids":["28324111"],"confidence":"Medium","gaps":["Localization-based mechanism later revised","Molecular role in retina not defined"]},{"year":2022,"claim":"Identified the cellular basis of retinal degeneration, showing RPE-specific (not Müller glia) ARAP1 loss recapitulates the phenotype through a defect in outer-segment phagocytosis.","evidence":"Conditional cell-type-specific knockouts, in vivo phagocytosis quantification, and Co-IP mass spectrometry","pmids":["35758026"],"confidence":"High","gaps":["MS interactors are candidate not validated","Direct molecular step in phagocytosis machinery unresolved"]},{"year":2020,"claim":"Connected ARAP1's CIN85/Cbl-competition mechanism to disease, showing it sustains EGFR/TGF-β/Smad3 signaling in high-glucose tubular cells, with the lncRNA ARAP1-AS2 binding ARAP1 to promote this axis.","evidence":"Co-IP, ubiquitination assay, RNA pulldown, and knockdown/overexpression","pmids":["32969198"],"confidence":"Medium","gaps":["Functional consequence of lncRNA binding on ARAP1 activity unclear","Single-lab corroboration of prior model"]},{"year":2023,"claim":"Demonstrated a tumor-suppressive role in lung adenocarcinoma, with ARAP1 RhoGAP activity inhibiting migration and invasion by suppressing Rho-driven stress fibers.","evidence":"Wild-type vs RhoGAP-dead overexpression, transwell assays, mouse metastasis model, and F-actin staining","pmids":["38008882"],"confidence":"Medium","gaps":["Endogenous loss-of-function not tested","RhoA as the specific GTPase inferred not directly measured"]},{"year":2025,"claim":"Defined how ARAP1 RhoGAP activity is targeted, showing its Ras-association domain binds Rap1 and Rac1 to enable RhoA inhibition and suppress chemokine-directed lymphocyte migration.","evidence":"Knockout cells, FRET RhoA biosensor, Rap1/Rac1 binding assays, live imaging, and domain-mutant rescue","pmids":["41488654"],"confidence":"Medium","gaps":["Structural basis of RA-domain dual binding unknown","Coupling between RA-domain occupancy and GAP catalysis not resolved"]},{"year":2025,"claim":"Revealed an unexpected mitochondrial input and proteasomal control of ARAP1, linking mitochondrial activity to ARAP1-dependent CDR formation and macropinocytosis in hepatocellular carcinoma.","evidence":"CRISPR knockout, confocal/SEM, macropinocytosis assays, MG132, CCCP, and Golgicide A perturbations","pmids":["39934854"],"confidence":"Medium","gaps":["Mechanism of mitochondrial localization unknown","How mitochondrial dysfunction blocks CDRs is undefined"]},{"year":null,"claim":"It remains unresolved how ARAP1's two GAP activities, multiple phosphoinositide and small-GTPase inputs, phosphorylation, and degradation are integrated to select among its diverse cargo and actin outputs in a given cell type.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unifying structural model of full-length ARAP1 regulation","Spatial/temporal coordination of Arf vs Rho GAP activities unknown","Physiological substrate selectivity across tissues undefined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[0,4,7]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[6,10]},{"term_id":"GO:0008289","term_label":"lipid binding","supporting_discovery_ids":[0,4]}],"localization":[{"term_id":"GO:0005794","term_label":"Golgi apparatus","supporting_discovery_ids":[0,3]},{"term_id":"GO:0005768","term_label":"endosome","supporting_discovery_ids":[2,3]},{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[1,7,20]},{"term_id":"GO:0005739","term_label":"mitochondrion","supporting_discovery_ids":[20]}],"pathway":[{"term_id":"R-HSA-5653656","term_label":"Vesicle-mediated transport","supporting_discovery_ids":[2,3,7]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[2,6,19]},{"term_id":"R-HSA-9609507","term_label":"Protein localization","supporting_discovery_ids":[1,8,9]}],"complexes":[],"partners":["CIN85","PTK6","EGFR","ARF1","ARF5","RAP1","RAC1","AP-3"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q96P48","full_name":"Arf-GAP with Rho-GAP domain, ANK repeat and PH domain-containing protein 1","aliases":["Centaurin-delta-2","Cnt-d2"],"length_aa":1450,"mass_kda":162.2,"function":"Phosphatidylinositol 3,4,5-trisphosphate-dependent GTPase-activating protein that modulates actin cytoskeleton remodeling by regulating ARF and RHO family members (PubMed:11804590, PubMed:19666464). Activated by phosphatidylinositol 3,4,5-trisphosphate (PtdIns(3,4,5)P3) binding and, to a lesser extent, by phosphatidylinositol 3,4-bisphosphate (PtdIns(3,4)P2) binding (PubMed:11804590). Has a preference for ARF1 and ARF5 (PubMed:11804590, PubMed:19666464). Positively regulates the ring size of circular dorsal ruffles and promotes macropinocytosis (PubMed:22573888). Acts as a bridging factor in osteoclasts to control actin and membrane dynamics (By similarity). Regulates the condensing of osteoclast podosomes into sealing zones which segregate the bone-facing membrane from other membrane domains and are required for osteoclast resorption activity (By similarity). Also regulates recruitment of the AP-3 complex to endosomal membranes and trafficking of lysosomal membrane proteins to the ruffled membrane border of osteoclasts to modulate bone resorption (By similarity). Regulates the endocytic trafficking of EGFR (PubMed:18764928, PubMed:18939958, PubMed:21275903). Regulates the incorporation of CD63 and CD9 into multivesicular bodies (PubMed:38682696). Required in the retinal pigment epithelium (RPE) for photoreceptor survival due to its role in promoting RPE phagocytosis (By similarity)","subcellular_location":"Cytoplasm; Golgi apparatus, trans-Golgi network; Golgi apparatus, Golgi stack; Cell membrane; Endosome, multivesicular body; Cell projection, ruffle; Cell projection, podosome; Early endosome","url":"https://www.uniprot.org/uniprotkb/Q96P48/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/ARAP1","classification":"Not Classified","n_dependent_lines":11,"n_total_lines":1208,"dependency_fraction":0.009105960264900662},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"CAPZB","stoichiometry":0.2},{"gene":"DNAJB6","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/ARAP1","total_profiled":1310},"omim":[{"mim_id":"606647","title":"ARF-GAP, RHO-GAP, ANKYRIN REPEAT, AND PLECKSTRIN HOMOLOGY DOMAINS-CONTAINING PROTEIN 3; ARAP3","url":"https://www.omim.org/entry/606647"},{"mim_id":"606646","title":"ARF-GAP, RHO-GAP, ANKYRIN REPEAT, AND PLECKSTRIN HOMOLOGY DOMAINS-CONTAINING PROTEIN 1; ARAP1","url":"https://www.omim.org/entry/606646"},{"mim_id":"606645","title":"ARF-GAP, RHO-GAP, ANKYRIN REPEAT, AND PLECKSTRIN HOMOLOGY DOMAINS-CONTAINING PROTEIN 2; ARAP2","url":"https://www.omim.org/entry/606645"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Nucleoplasm","reliability":"Approved"},{"location":"Plasma membrane","reliability":"Approved"},{"location":"Vesicles","reliability":"Additional"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/ARAP1"},"hgnc":{"alias_symbol":[],"prev_symbol":["CENTD2"]},"alphafold":{"accession":"Q96P48","domains":[{"cath_id":"1.10.150.50","chopping":"12-67","consensus_level":"high","plddt":86.9493,"start":12,"end":67},{"cath_id":"2.30.29.30","chopping":"332-425","consensus_level":"medium","plddt":87.3484,"start":332,"end":425},{"cath_id":"2.30.29.30","chopping":"445-533","consensus_level":"medium","plddt":88.1179,"start":445,"end":533},{"cath_id":"1.10.220.150","chopping":"535-720","consensus_level":"medium","plddt":92.5427,"start":535,"end":720},{"cath_id":"2.30.29.30","chopping":"740-850","consensus_level":"medium","plddt":89.6135,"start":740,"end":850},{"cath_id":"2.30.29.30","chopping":"858-955","consensus_level":"medium","plddt":83.2815,"start":858,"end":955},{"cath_id":"1.10.555.10","chopping":"961-1165","consensus_level":"high","plddt":88.0433,"start":961,"end":1165},{"cath_id":"2.30.29.30","chopping":"1175-1290_1297-1318_1334-1397","consensus_level":"medium","plddt":84.7263,"start":1175,"end":1397}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q96P48","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q96P48-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q96P48-F1-predicted_aligned_error_v6.png","plddt_mean":74.88},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=ARAP1","jax_strain_url":"https://www.jax.org/strain/search?query=ARAP1"},"sequence":{"accession":"Q96P48","fasta_url":"https://rest.uniprot.org/uniprotkb/Q96P48.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q96P48/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q96P48"}},"corpus_meta":[{"pmid":"11804590","id":"PMC_11804590","title":"ARAP1: 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Its Rho GAP activity mediates cell rounding and loss of stress fibers when overexpressed. Its Arf GAP activity mediates changes in the Golgi apparatus and formation of filopodia via increased cellular Cdc42 activity. Both activities contribute to inhibiting cell spreading. ARAP1 associates with the Golgi.\",\n      \"method\": \"In vitro GAP assays, overexpression in cells, immunofluorescence/localization studies\",\n      \"journal\": \"Molecular cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — in vitro enzymatic assays combined with cell biological readouts and mutagenesis-level domain dissection, founding paper replicated by subsequent studies\",\n      \"pmids\": [\"11804590\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"ARAP1 (the 493-aa isoform identified in this study, distinct from the multi-domain ARAP1) binds the carboxyl terminus of the AT1A angiotensin II receptor via yeast two-hybrid and co-immunoprecipitation, co-localizes with recycled AT1A at the plasma membrane, and promotes recycling of AT1A to the plasma membrane in HEK-293 cells, restoring Ca2+ release response to a second Ang II stimulation.\",\n      \"method\": \"Yeast two-hybrid, co-immunoprecipitation, immunocytochemistry, functional Ca2+ release assay\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 / Moderate — reciprocal Co-IP and functional assay in single lab; the identified protein is a shorter isoform but same gene locus\",\n      \"pmids\": [\"14559250\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"ARAP1 rapidly and transiently associates with the cell edge and with Rab5/rabaptin-5/EGFR-positive punctate structures that precede EEA1-positive early endosomes after EGF treatment. Recruitment requires active Rab5 and an EGFR-derived signal. siRNA knockdown of ARAP1 accelerates association of EGF with EEA1 endosomes, accelerates EGFR degradation, and diminishes/shortens ERK and JNK phosphorylation, demonstrating that ARAP1 retards early endocytic trafficking of EGFR and prolongs downstream signaling.\",\n      \"method\": \"siRNA knockdown, live-cell imaging, immunofluorescence colocalization, western blot for ERK/JNK phosphorylation\",\n      \"journal\": \"Traffic (Copenhagen, Denmark)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean RNAi with defined trafficking and signaling phenotypes, replicated independently in a companion paper (PMID 18764928)\",\n      \"pmids\": [\"18939958\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"ARAP1 localizes to the Golgi complex and to internal membranes of multivesicular bodies/late endosomes. Its distribution is controlled by phosphorylation and by binding to 3- and 4-phosphorylated phosphoinositides through its PH domains. ARAP1 knockdown causes EGFR accumulation in sorting/late endosomal compartments and inhibits EGFR degradation, resulting in prolonged EGF signaling, placing ARAP1 at a late step of EGFR endocytic trafficking.\",\n      \"method\": \"siRNA knockdown, immunofluorescence, subcellular fractionation, western blot\",\n      \"journal\": \"Traffic (Copenhagen, Denmark)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean KD with defined compartment-specific phenotype, independently replicated by Yoon et al. 2008 (PMID 18939958)\",\n      \"pmids\": [\"18764928\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"The first PH domain (PH1) of ARAP1 specifically binds PtdIns(3,4,5)P3 with ~1.6 µM affinity. PH1 does not mediate PtdIns(3,4,5)P3-dependent recruitment of ARAP1 to membranes in cells; instead, PtdIns(3,4,5)P3 binding to PH1 allosterically stimulates Arf GAP catalytic activity and is required for ARAP1's in vivo function in regulating EGFR endocytic trafficking.\",\n      \"method\": \"In vitro lipid-binding assay, in vitro Arf GAP activity assay, live-cell imaging, site-directed mutagenesis, EGFR trafficking assay\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution with mutagenesis plus in vivo trafficking readout, single lab with multiple orthogonal methods\",\n      \"pmids\": [\"19666464\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"PTK6 (Brk) associates with ARAP1 in an EGF/EGFR-dependent manner via its SH2 domain (requiring Arg105). PTK6 phosphorylates ARAP1 at Tyr231. Phosphorylation of ARAP1 at Y231 is required for ARAP1 to inhibit EGFR down-regulation; the Y231F mutant fails to do so. Silencing PTK6 in breast carcinoma cells decreases EGFR levels, placing ARAP1 phosphorylation by PTK6 as a mechanism that sustains EGFR signaling.\",\n      \"method\": \"Co-immunoprecipitation (Flag-PTK6 pull-down, MALDI-TOF MS identification of ARAP1), in vitro kinase assay, site-directed mutagenesis (Y231F), EGFR down-regulation assay, PTK6 siRNA\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Moderate — kinase assay, mutagenesis, and functional EGFR trafficking readout in single lab with multiple orthogonal methods\",\n      \"pmids\": [\"20554524\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"ARAP1 associates with CIN85 via its PXPXXRX motif (requiring Arg86 and Arg90) interacting with CIN85 SH3 domains. A CIN85-binding-deficient ARAP1 mutant fails to rescue the effect of ARAP1 knockdown on EGFR trafficking to the early endosome. Overexpression of ARAP1 reduces Cbl-mediated ubiquitination of EGFR and slows Cbl-dependent EGFR degradation, with ARAP1 proposed to compete with Cbl for CIN85 binding to divert EGFR away from the early endosome/lysosome degradation pathway.\",\n      \"method\": \"Co-immunoprecipitation, site-directed mutagenesis, siRNA knockdown of CIN85/ARAP1, EGFR ubiquitination assay, EGFR degradation assay\",\n      \"journal\": \"Biology of the cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP, mutagenesis, and multiple functional assays in single lab\",\n      \"pmids\": [\"21275903\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Growth factor stimulation induces localization of ARAP1 to the plasma membrane inside the ring structure of circular dorsal ruffles (CDRs). ARAP1 overexpression increases CDR ring size in an Arf GAP activity-dependent manner, while ARAP1 knockdown produces smaller CDRs. Expression of dominant-negative Arf1 or Arf5 (the substrates of ARAP1) also expands CDR size, placing Arf1 and Arf5 downstream of ARAP1 in CDR ring-size control.\",\n      \"method\": \"Fluorescence microscopy, ARAP1 overexpression, siRNA knockdown, dominant-negative Arf1/Arf5, Arf GAP-dead mutant\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis with dominant-negative Arfs plus GAP-dead mutant, clean KD phenotype, single lab with multiple orthogonal approaches\",\n      \"pmids\": [\"22573888\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"ARAP1 interacts with the intracellular portion of TRAIL death receptor DR4 (identified by yeast two-hybrid), co-precipitates with DR4, and co-localizes with it in the ER/Golgi, plasma membrane, and early endosomes of TRAIL-treated cells. ARAP1 knockdown significantly reduces DR4 surface localization in multiple tumor cell lines and slows TRAIL-induced cell death, implicating ARAP1 in DR4 trafficking to the cell surface.\",\n      \"method\": \"Yeast two-hybrid, co-immunoprecipitation, immunofluorescence colocalization, siRNA knockdown, flow cytometry (surface DR4), cell death assay\",\n      \"journal\": \"Apoptosis : an international journal on programmed cell death\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 / Moderate — yeast two-hybrid corroborated by Co-IP and functional siRNA data, single lab\",\n      \"pmids\": [\"18165900\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"In osteoclasts, ARAP1 is part of a protein complex at podosomes/sealing zones where its RhoGAP domain regulates actin dynamics. At endosomes, ARAP1 interacts with AP-3 adaptor complexes where its Arf GAP domain regulates Arf1-dependent AP-3 binding to membranes and lysosomal membrane protein transport to ruffled borders. ARAP1 or AP-3 depletion in osteoclasts impairs their capacity to digest bone in vitro.\",\n      \"method\": \"Co-immunoprecipitation, immunofluorescence, siRNA knockdown, bone resorption assay in vitro, domain-specific mutant analysis\",\n      \"journal\": \"iScience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP and functional bone-resorption assay with domain dissection, single lab\",\n      \"pmids\": [\"30240610\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"The ARAP1 PXPXXRX(except P)XXR/H/K motif binds the CIN85 SH3B domain with high affinity and specificity. Crystal/biochemical structure shows that the β2–β3 loops of CIN85 SH3 domains and the H87(ARAP1)/E132(CIN85) interaction are critical for binding specificity. ARAP1 competes with Cbl for CIN85 binding as demonstrated by competitive analytical gel-filtration chromatography and isothermal titration calorimetry.\",\n      \"method\": \"Biochemical binding assays, structural (domain-swap analysis, structure alignment), isothermal titration calorimetry (ITC), analytical gel-filtration chromatography\",\n      \"journal\": \"Biochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — structural and thermodynamic characterization with ITC, competitive binding assay, multiple orthogonal biophysical methods in single study\",\n      \"pmids\": [\"29589748\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Arap1-deficient mice show accelerated sepsis-induced hypotension and reduced vascular sensitivity to angiotensin II (measured in isolated perfused kidney), confirming that Arap1 is required for normal AT1 receptor-dependent vasoconstriction. During endotoxemia, Arap1 expression is successively down-regulated in wildtype mice (to <10% baseline), and this down-regulation can be recapitulated in cultured mesangial cells by TNFα and IFNγ.\",\n      \"method\": \"Arap1 knockout mice, telemetry blood pressure measurement, isolated perfused kidney assay, LPS-induced endotoxemia model, cytokine treatment of cultured cells\",\n      \"journal\": \"Critical care (London, England)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic KO with defined vascular phenotype and in vitro mechanistic follow-up, single lab\",\n      \"pmids\": [\"23844607\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"Proximal-tubule-specific overexpression of ARAP1 in transgenic mice causes hypertension (~20–25 mmHg increase in systolic BP), decreased urine volume, and kidney hypertrophy. The hypertension is completely normalized by renin-angiotensin system inhibition and prevented by low-salt diet, placing renal ARAP1 in regulation of BP via the intrarenal renin-angiotensin system.\",\n      \"method\": \"Transgenic mouse overexpression (proximal tubule-specific), telemetry/tail-cuff BP measurement, pharmacological RAS inhibition, dietary salt manipulation\",\n      \"journal\": \"Hypertension (Dallas, Tex. : 1979)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo transgenic model with pharmacological rescue, single lab\",\n      \"pmids\": [\"16801480\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"In vivo, Arap1 protein is restricted to the renal vasculature and glomerular mesangial cells (absent from tubular epithelia). Angiotensin II infusion suppresses renal Arap1 mRNA and protein, while AT1 antagonism (losartan) increases Arap1 expression. Angiotensin II also suppresses Arap1 in cultured mesangial cells in a time- and dose-dependent manner, establishing a negative feedback loop between Ang II signaling and Arap1 expression.\",\n      \"method\": \"Immunohistochemistry (localization in mouse and human kidneys), in vivo Ang II infusion, losartan treatment, renal artery stenosis, water restriction models; western blot and RT-PCR of Arap1\",\n      \"journal\": \"American journal of physiology. Renal physiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 / Moderate — direct localization by IHC with functional regulation confirmed by multiple in vivo manipulations, single lab\",\n      \"pmids\": [\"22357923\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Arap1 knockout mice develop photoreceptor degeneration starting at 4 weeks postnatal. Immunohistochemistry detects Arap1 predominantly in Müller glia (not photoreceptors), implicating a non-cell-autonomous Müller glia-dependent mechanism for photoreceptor survival.\",\n      \"method\": \"Germline Arap1 knockout mice (KOMP2), optical coherence tomography, fundus photography, immunohistochemistry, electroretinography\",\n      \"journal\": \"Investigative ophthalmology & visual science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — clean KO phenotype with localization data, but mechanism not fully defined; single lab/screen\",\n      \"pmids\": [\"28324111\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Conditional knockout of Arap1 in RPE (Vmd2-Cre) but not Müller glia (Glast-Cre) recapitulates the photoreceptor degeneration of germline Arap1-/- mice. Arap1-/- mice show a clear phagocytic defect in RPE outer segment phagocytosis in vivo. Mass spectrometry of ARAP1 co-immunoprecipitation identifies candidate interactors involved in phagocytosis, cytoskeletal organization, intracellular trafficking and endocytosis, establishing that ARAP1 expression in RPE is required for photoreceptor survival via its role in RPE phagocytosis.\",\n      \"method\": \"Conditional (cell-type-specific) Arap1 knockout mice, in vivo outer segment phagocytosis quantification, mass spectrometry of ARAP1 co-IP\",\n      \"journal\": \"Disease models & mechanisms\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — cell-type-specific KO with defined cellular phenotype (phagocytosis assay) and MS interactome, single lab with multiple orthogonal approaches\",\n      \"pmids\": [\"35758026\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"ARAP1 maintains persistent EGFR activation in high-glucose-treated renal tubular cells by reducing EGFR ubiquitination through competing with Cbl for CIN85 binding, as shown by co-immunoprecipitation and ubiquitination assays. The lncRNA ARAP1-AS2 directly interacts with ARAP1 (RNA pulldown), and overexpression of ARAP1-AS2 promotes this EGFR/TGF-β/Smad3 signaling.\",\n      \"method\": \"Co-immunoprecipitation, ubiquitination assay, RNA pulldown, dual-immunofluorescence, siRNA knockdown/overexpression\",\n      \"journal\": \"Journal of cellular and molecular medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 / Moderate — Co-IP and ubiquitination assay corroborate the CIN85-competition model from PMID 21275903, single lab\",\n      \"pmids\": [\"32969198\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"ARAP1 overexpression significantly inhibits migration and invasion of lung adenocarcinoma cells in vitro and in vivo, and this effect depends on its RhoGAP activity; the mechanism is suppression of Rho signaling leading to inhibition of stress fiber formation.\",\n      \"method\": \"Overexpression of wild-type vs. RhoGAP-dead ARAP1 mutant, transwell migration/invasion assays, mouse metastasis model, F-actin staining\",\n      \"journal\": \"Discover oncology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — domain-specific mutant with functional phenotype, single lab, single study\",\n      \"pmids\": [\"38008882\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"ARAP1 knockdown in high-glucose-treated HK-2 renal tubular cells decreases Cdc42-GTP levels and reduces cytoskeleton reorganization, cell viability, migration, and EMT/fibrosis marker expression, placing ARAP1 upstream of Cdc42 activation in this cellular context.\",\n      \"method\": \"siRNA knockdown of ARAP1, Cdc42-GTP pull-down (CRIB assay), cell migration assay, western blot for EMT markers\",\n      \"journal\": \"Journal of cellular physiology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single KD experiment with downstream Cdc42-GTP measurement, single lab\",\n      \"pmids\": [\"31975379\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"ARAP1 is transiently recruited to cell protrusions following chemokine stimulation in lymphocytes. Its Ras-association (RA) domain binds Rap1 and Rac1, and this binding is required for ARAP1-mediated RhoA inhibition. ARAP1-deficient cells show enhanced chemokine-directed migration with increased RhoA activation and F-actin polymerization. ARAP1 overexpression inhibits migration in a RhoGAP domain-dependent manner.\",\n      \"method\": \"ARAP1 knockout cells, FRET-based RhoA biosensor, Rap1/Rac1 pulldown/binding assay, live-cell imaging of ARAP1 localization, domain-mutant overexpression, migration assay\",\n      \"journal\": \"Frontiers in immunology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic KO with FRET biosensor readout and domain-specific rescue/mutant analysis, single lab with multiple orthogonal methods\",\n      \"pmids\": [\"41488654\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"In Hep3B hepatocellular carcinoma cells, ARAP1 localizes to circular dorsal ruffles (CDRs) and to mitochondria (not seen in control HCC lines). ARAP1 KO reduces CDR size, disrupts lamellipodia within CDRs, attenuates extracellular solute uptake (macropinocytosis), and reduces cell growth and malignant potential. ARAP1 is actively degraded via the proteasome in Hep3B cells (MG132 restores levels), and mitochondrial dysfunction (CCCP) blocks CDRs, linking mitochondrial activity to ARAP1-dependent CDR formation.\",\n      \"method\": \"ARAP1 CRISPR knockout, confocal microscopy, scanning electron microscopy, macropinocytosis uptake assay, proteasome inhibitor (MG132), mitochondrial inhibitor (CCCP), ARF1 inhibitor (Golgicide A), cell proliferation/invasion assays\",\n      \"journal\": \"Cell communication and signaling : CCS\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — CRISPR KO with multiple cell-biological readouts and pharmacological perturbations, single lab\",\n      \"pmids\": [\"39934854\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"ARAP1 is a PtdIns(3,4,5)P3-dependent dual GTPase-activating protein (Arf GAP and Rho GAP) that localizes to the Golgi, endosomes, and cell protrusions, where it acts as a signaling hub: its Arf GAP activity (stimulated allosterically by PIP3 binding to PH1 and directed at Arf1/Arf5) controls circular dorsal ruffle size, AP-3-dependent lysosomal trafficking in osteoclasts, and the early-to-late endosomal transit of EGFR, while its Rho GAP activity suppresses RhoA-driven actin stress fiber formation and cell migration; PTK6 phosphorylates ARAP1 at Tyr231 to enhance EGFR retention, and ARAP1 competes with Cbl for CIN85 SH3B binding (structurally defined) to reduce EGFR ubiquitination and slow receptor degradation; ARAP1 also traffics DR4 and AT1 receptors to the plasma membrane and, in retinal pigment epithelium, is required for outer-segment phagocytosis and photoreceptor survival.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"ARAP1 is a phosphoinositide-regulated dual GTPase-activating protein that integrates membrane lipid signals with Arf and Rho family GTPase output to control membrane trafficking and actin-dependent cell-surface dynamics [#0]. It carries both an Arf GAP and a Rho GAP activity: PtdIns(3,4,5)P3 binding to its first PH domain allosterically stimulates the Arf GAP catalytic activity that acts on Arf1 and Arf5, while the Rho GAP activity drives loss of stress fibers and inhibits cell spreading [#0, #4, #7]. Through these activities ARAP1 localizes to the Golgi and to late endosomal/multivesicular compartments and governs growth-factor receptor trafficking: it is recruited in a Rab5- and EGFR-dependent manner to early endocytic structures and retards the transit of EGFR into degradative compartments, thereby prolonging downstream ERK/JNK signaling [#2, #3]. ARAP1 slows EGFR degradation by binding the adaptor CIN85 through a proline-arginine motif and competing with Cbl for the CIN85 SH3B domain, reducing EGFR ubiquitination — an interaction defined structurally and thermodynamically [#6, #10]; PTK6 phosphorylates ARAP1 at Tyr231 to reinforce EGFR retention [#5]. The Arf GAP activity also sets the size of growth-factor-induced circular dorsal ruffles downstream of Arf1/Arf5 and supports macropinocytosis [#7, #20], and ARAP1 directs surface delivery of the death receptor DR4 and the AT1 angiotensin II receptor [#8, #1]. The Rho GAP activity, dependent on Rap1/Rac1 binding through the Ras-association domain, suppresses RhoA-driven actin polymerization and cell migration in lymphocytes and tumor cells [#17, #19]. In vivo, ARAP1 functions in osteoclast bone resorption via AP-3-dependent lysosomal protein transport [#9], in renal vascular angiotensin II responsiveness and blood-pressure control [#11, #12], and in retinal pigment epithelium, where it is required for outer-segment phagocytosis and photoreceptor survival [#15].\"\n  ,\n  \"teleology\": [\n    {\n      \"year\": 2002,\n      \"claim\": \"Established ARAP1 as a bifunctional PIP3-dependent Arf GAP and Rho GAP that couples phosphoinositide signaling to both Golgi/filopodial dynamics and stress-fiber loss, defining its core enzymatic identity.\",\n      \"evidence\": \"In vitro GAP assays plus overexpression and localization studies in cells\",\n      \"pmids\": [\"11804590\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not define the physiological substrate Arf isoforms in vivo\", \"Mechanism of PIP3 dependence not yet resolved at the domain level\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Linked an ARAP1 isoform to G-protein-coupled receptor recycling, showing it promotes AT1A angiotensin receptor return to the plasma membrane to restore signaling competence.\",\n      \"evidence\": \"Yeast two-hybrid, reciprocal Co-IP, immunocytochemistry, and Ca2+ release assay in HEK-293 cells\",\n      \"pmids\": [\"14559250\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Used a short 493-aa isoform distinct from full-length ARAP1\", \"GAP-domain involvement in recycling not tested\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Resolved ARAP1's role in EGFR trafficking from both ends of the endocytic route, showing it is recruited to early Rab5/EGFR structures and retards transit to EEA1 endosomes while also acting at late sorting/MVB compartments to slow receptor degradation and prolong signaling.\",\n      \"evidence\": \"siRNA knockdown, live-cell imaging, colocalization, subcellular fractionation, and ERK/JNK phospho-blots (two companion studies)\",\n      \"pmids\": [\"18939958\", \"18764928\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not identify the molecular tether retaining EGFR\", \"Relative contribution of early vs late steps unresolved\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Extended ARAP1's trafficking function to death-receptor delivery, implicating it in routing DR4 to the cell surface to enable TRAIL-induced apoptosis.\",\n      \"evidence\": \"Yeast two-hybrid, Co-IP, colocalization, siRNA, surface flow cytometry, and cell-death assays in tumor lines\",\n      \"pmids\": [\"18165900\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"GAP-domain dependence not dissected\", \"Single-lab interaction without structural detail\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Defined the mechanism of phosphoinositide control, showing PH1 binds PtdIns(3,4,5)P3 not to recruit ARAP1 but to allosterically stimulate its Arf GAP catalysis, which is required for EGFR trafficking function.\",\n      \"evidence\": \"In vitro lipid-binding and Arf GAP assays, mutagenesis, and EGFR trafficking readouts\",\n      \"pmids\": [\"19666464\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Membrane recruitment mechanism left unexplained\", \"Structural basis of allostery not solved\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Identified an upstream regulatory input, showing PTK6 binds and phosphorylates ARAP1 at Tyr231 to enforce EGFR retention and sustain receptor signaling.\",\n      \"evidence\": \"Co-IP/MS, in vitro kinase assay, Y231F mutagenesis, and EGFR down-regulation and PTK6 siRNA assays\",\n      \"pmids\": [\"20554524\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How Y231 phosphorylation alters ARAP1 activity is unknown\", \"Crosstalk with PIP3 regulation untested\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Established the adaptor mechanism by which ARAP1 slows EGFR degradation, showing it binds CIN85 via a PXPXXRX motif and competes with Cbl to reduce EGFR ubiquitination and divert it from the degradative pathway.\",\n      \"evidence\": \"Co-IP, mutagenesis, CIN85/ARAP1 siRNA, ubiquitination and degradation assays\",\n      \"pmids\": [\"21275903\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Competition shown functionally but not yet structurally\", \"Did not measure binding affinities\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Placed Arf1/Arf5 as direct effectors of ARAP1 in actin remodeling, demonstrating that ARAP1 Arf GAP activity sets circular dorsal ruffle ring size.\",\n      \"evidence\": \"Microscopy with overexpression, knockdown, dominant-negative Arf1/Arf5, and GAP-dead mutant epistasis\",\n      \"pmids\": [\"22573888\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional purpose of CDR size control not established\", \"Link to receptor internalization untested\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Located endogenous ARAP1 to renal vasculature/mesangium and revealed a negative feedback loop in which angiotensin II suppresses ARAP1 expression and AT1 blockade raises it.\",\n      \"evidence\": \"IHC localization with in vivo Ang II infusion, losartan, and mesangial cell culture\",\n      \"pmids\": [\"22357923\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular mechanism of transcriptional suppression unknown\", \"Connection to AT1 trafficking not directly demonstrated in vivo\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Provided genetic evidence that ARAP1 is required for AT1-dependent vasoconstriction, with knockout mice showing impaired angiotensin II vascular sensitivity and worsened sepsis-induced hypotension.\",\n      \"evidence\": \"Arap1 knockout mice, telemetry, isolated perfused kidney, LPS endotoxemia, and cytokine treatment of cells\",\n      \"pmids\": [\"23844607\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Did not pinpoint the cellular site of action\", \"Mechanistic link to AT1 receptor trafficking inferred not proven\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Showed renal ARAP1 controls blood pressure, with proximal-tubule overexpression causing RAS-dependent, salt-sensitive hypertension.\",\n      \"evidence\": \"Proximal-tubule-specific transgenic mice with BP telemetry, RAS inhibition, and dietary salt manipulation\",\n      \"pmids\": [\"16801480\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular mechanism downstream of ARAP1 overexpression unresolved\", \"Cell-autonomous tubular pathway not defined\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Solved the structural and thermodynamic basis of the ARAP1–CIN85 interaction, mapping the SH3B-binding motif and confirming direct competition with Cbl by ITC and gel filtration.\",\n      \"evidence\": \"Structural domain-swap analysis, ITC, and competitive analytical gel-filtration chromatography\",\n      \"pmids\": [\"29589748\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not test the structural model in cellular EGFR trafficking\", \"In vivo stoichiometry with Cbl unknown\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Extended ARAP1's dual-GAP logic to osteoclast bone resorption, with the RhoGAP domain acting at podosomes and the Arf GAP domain governing Arf1-dependent AP-3 recruitment for lysosomal protein transport.\",\n      \"evidence\": \"Co-IP, immunofluorescence, siRNA, domain-mutant analysis, and in vitro bone resorption assay\",\n      \"pmids\": [\"30240610\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab interactome\", \"How the two GAP activities are spatially coordinated is unclear\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Implicated ARAP1 in photoreceptor survival, with knockout mice degenerating and initial localization pointing to a non-cell-autonomous Müller glia mechanism.\",\n      \"evidence\": \"Germline Arap1 knockout mice with OCT, fundus imaging, IHC, and ERG\",\n      \"pmids\": [\"28324111\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Localization-based mechanism later revised\", \"Molecular role in retina not defined\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Identified the cellular basis of retinal degeneration, showing RPE-specific (not Müller glia) ARAP1 loss recapitulates the phenotype through a defect in outer-segment phagocytosis.\",\n      \"evidence\": \"Conditional cell-type-specific knockouts, in vivo phagocytosis quantification, and Co-IP mass spectrometry\",\n      \"pmids\": [\"35758026\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"MS interactors are candidate not validated\", \"Direct molecular step in phagocytosis machinery unresolved\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Connected ARAP1's CIN85/Cbl-competition mechanism to disease, showing it sustains EGFR/TGF-β/Smad3 signaling in high-glucose tubular cells, with the lncRNA ARAP1-AS2 binding ARAP1 to promote this axis.\",\n      \"evidence\": \"Co-IP, ubiquitination assay, RNA pulldown, and knockdown/overexpression\",\n      \"pmids\": [\"32969198\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional consequence of lncRNA binding on ARAP1 activity unclear\", \"Single-lab corroboration of prior model\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Demonstrated a tumor-suppressive role in lung adenocarcinoma, with ARAP1 RhoGAP activity inhibiting migration and invasion by suppressing Rho-driven stress fibers.\",\n      \"evidence\": \"Wild-type vs RhoGAP-dead overexpression, transwell assays, mouse metastasis model, and F-actin staining\",\n      \"pmids\": [\"38008882\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Endogenous loss-of-function not tested\", \"RhoA as the specific GTPase inferred not directly measured\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Defined how ARAP1 RhoGAP activity is targeted, showing its Ras-association domain binds Rap1 and Rac1 to enable RhoA inhibition and suppress chemokine-directed lymphocyte migration.\",\n      \"evidence\": \"Knockout cells, FRET RhoA biosensor, Rap1/Rac1 binding assays, live imaging, and domain-mutant rescue\",\n      \"pmids\": [\"41488654\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Structural basis of RA-domain dual binding unknown\", \"Coupling between RA-domain occupancy and GAP catalysis not resolved\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Revealed an unexpected mitochondrial input and proteasomal control of ARAP1, linking mitochondrial activity to ARAP1-dependent CDR formation and macropinocytosis in hepatocellular carcinoma.\",\n      \"evidence\": \"CRISPR knockout, confocal/SEM, macropinocytosis assays, MG132, CCCP, and Golgicide A perturbations\",\n      \"pmids\": [\"39934854\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of mitochondrial localization unknown\", \"How mitochondrial dysfunction blocks CDRs is undefined\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"It remains unresolved how ARAP1's two GAP activities, multiple phosphoinositide and small-GTPase inputs, phosphorylation, and degradation are integrated to select among its diverse cargo and actin outputs in a given cell type.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unifying structural model of full-length ARAP1 regulation\", \"Spatial/temporal coordination of Arf vs Rho GAP activities unknown\", \"Physiological substrate selectivity across tissues undefined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [0, 4, 7]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [6, 10]},\n      {\"term_id\": \"GO:0008289\", \"supporting_discovery_ids\": [0, 4]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005794\", \"supporting_discovery_ids\": [0, 3]},\n      {\"term_id\": \"GO:0005768\", \"supporting_discovery_ids\": [2, 3]},\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [1, 7, 20]},\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [20]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-5653656\", \"supporting_discovery_ids\": [2, 3, 7]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [2, 6, 19]},\n      {\"term_id\": \"R-HSA-9609507\", \"supporting_discovery_ids\": [1, 8, 9]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"CIN85\", \"PTK6\", \"EGFR\", \"Arf1\", \"Arf5\", \"Rap1\", \"Rac1\", \"AP-3\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}