{"gene":"SHB","run_date":"2026-04-28T20:42:07","timeline":{"discoveries":[{"year":1994,"finding":"SHB was identified as a novel SH2 domain-containing adaptor protein with proline-rich domains; its SH2 domain fusion protein binds the autophosphorylated PDGF β-receptor but not the EGF receptor, establishing SHB as a signal transduction adaptor linking SH3 domain proteins to tyrosine kinase receptors.","method":"GST-SH2 fusion protein pulldown, Western blot, cDNA cloning and transient/stable transfection","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 2 — foundational characterization with multiple orthogonal methods (pulldown, immunoblot, transfection), replicated in subsequent studies","pmids":["8302579"],"is_preprint":false},{"year":1995,"finding":"The SHB SH2 domain preferentially binds the phosphopeptide motif pTyr-Thr/Val/Ile-X-Leu; it binds multiple autophosphorylation sites on the PDGF β-receptor and phosphorylated FGFR-1 (mainly via Y776); the proline-rich motifs (pro-4/pro-5) bind Src, p85α PI3-kinase, and Eps8 SH3 domains in vitro, and in vivo association with v-Src and Eps8 was confirmed by co-immunoprecipitation.","method":"Degenerate phosphopeptide library screening, competing peptides with PDGF receptor Y→F mutants, GST-SH3 fusion protein pulldowns, co-immunoprecipitation","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 1 — in vitro binding assays with mutagenesis plus co-IP validation, multiple orthogonal approaches","pmids":["7537362"],"is_preprint":false},{"year":1996,"finding":"Overexpression of SHB in NIH3T3 fibroblasts causes apoptosis (pyknotic nuclei by TUNEL) under low-serum conditions, which is rescued by PDGF-BB but not IGF-1, establishing SHB as a mediator of apoptotic signaling downstream of specific tyrosine kinase receptors.","method":"Stable transfection, TUNEL staining, cell counting, PDGF/IGF-1 rescue experiments","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 — clean overexpression with defined phenotypic readout (apoptosis), single lab","pmids":["8806685"],"is_preprint":false},{"year":1997,"finding":"SHB overexpression in NIH3T3 cells downregulates Eps8 protein and mRNA, increases basal PI3-kinase activity, and elevates STAT1 mRNA and protein levels, indicating that SHB modulates expression and activity of SH3 domain signaling proteins.","method":"Western blot, Northern blot, in vitro PI3-kinase assay in SHB-overexpressing cells","journal":"Experimental cell research","confidence":"Medium","confidence_rationale":"Tier 3 — overexpression correlation with signaling changes, single lab, single approach per readout","pmids":["9087167"],"is_preprint":false},{"year":1998,"finding":"SHB is expressed in Jurkat T cells and, upon TCR stimulation, forms multiprotein complexes: Grb2 binds SHB proline-rich motifs via its SH3 domains; the SHB SH2 domain associates with the TCR ζ-chain (p22); a central PTB domain (preferring Asp-Asp-X-pTyr) binds p36/38 (possibly Lnk); overexpression of SHB increases basal phosphorylation of associated proteins, and the R522K SH2-inactive mutant reduces CD3-stimulated tyrosine phosphorylation.","method":"Co-immunoprecipitation, phosphopeptide library, dominant-negative mutant overexpression, Western blot","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods (co-IP, peptide library, mutagenesis), replicated in subsequent TCR papers","pmids":["9484780"],"is_preprint":false},{"year":1998,"finding":"SHB overexpression in PC12 cells enhances NGF- and bFGF-induced neurite outgrowth in an SH2 domain-dependent manner; SHB is tyrosine phosphorylated and co-immunoprecipitates with a 140 kDa phosphotyrosine protein upon NGF treatment, placing SHB downstream of TrkA/FGFR in neuronal differentiation signaling.","method":"Stable transfection, neurite outgrowth assay, immunoprecipitation, Western blot","journal":"Cell growth & differentiation","confidence":"Medium","confidence_rationale":"Tier 2 — SH2 domain mutagenesis plus co-IP, clean cellular phenotype readout, single lab","pmids":["9751119"],"is_preprint":false},{"year":1999,"finding":"SHB associates with PLC-γ1 in Jurkat T cells; expression of SH2-defective SHB diminishes LAT phosphorylation, blocks PLC-γ1 phosphorylation, abolishes calcium rise, suppresses MAPK activation, prevents NFAT activation, and reduces endogenous IL-2 production upon TCR stimulation.","method":"Co-immunoprecipitation, dominant-negative overexpression, calcium imaging, NFAT reporter assay, cytokine ELISA","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 — multiple downstream readouts with dominant-negative mutant, mechanistic pathway placement","pmids":["10488157"],"is_preprint":false},{"year":1999,"finding":"Transgenic mice overexpressing SHB in β-cells (under rat insulin promoter) show increased β-cell area, enhanced glucose-stimulated insulin secretion, higher islet DNA content, and elevated apoptosis under cytokine or low-serum stress, establishing a dual role for SHB in β-cell proliferation and death.","method":"Transgenic mouse generation, glucose tolerance test, islet isolation, insulin secretion assay, TUNEL staining","journal":"Molecular medicine","confidence":"Medium","confidence_rationale":"Tier 2 — in vivo transgenic model with multiple functional readouts, single lab","pmids":["10404514"],"is_preprint":false},{"year":2000,"finding":"Endostatin induces tyrosine phosphorylation of SHB and formation of multiprotein complexes in endothelial cells; the SHB SH2 domain pull-down co-precipitates a 125 kDa phosphotyrosyl protein with intrinsic or associated tyrosine kinase activity; SHB overexpression in IBE cells enhances endostatin-induced apoptosis in an SH2 domain- and endostatin heparin-binding-dependent manner.","method":"Western blot for pTyr-SHB, SH2 domain fusion protein pulldown, overexpression with SH2 mutant, apoptosis assays","journal":"Blood","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods (pulldown, co-IP, mutagenesis, functional apoptosis assay), highly cited","pmids":["10828022"],"is_preprint":false},{"year":2000,"finding":"GTK (FRK/RAK) overexpression in PC12 cells causes increased FAK content, phosphorylation of SHB, and association between SHB and FAK; this correlates with CrkII complex formation with p130Cas, FAK and SHB, and Rap1 activation required for neurite outgrowth, placing SHB downstream of GTK in a FAK/CrkII/Rap1 pathway.","method":"Western blot, co-immunoprecipitation, Rap1 activity assay (RalGDS-RBD pulldown), dominant-negative transfection, neurite outgrowth assay","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 — co-IP plus functional pathway validation with dominant negatives, single lab","pmids":["10878015"],"is_preprint":false},{"year":2000,"finding":"SHB overexpression in PC12 cells enables NGF- and EGF- (but not FGF-2-) induced Rap1 activation in an SH2 domain-dependent manner; CrkII SH2 domain interacts with SHB and a 130-135 kDa phosphotyrosine protein; blocking Rap1 signaling (RalGDS-RBD or Rap1GAP) reduces SHB-dependent neurite outgrowth.","method":"Rap1 activity assay, co-immunoprecipitation, dominant-negative transfection, neurite outgrowth assay","journal":"Experimental cell research","confidence":"Medium","confidence_rationale":"Tier 2 — Rap1 pull-down activity assay plus functional pathway validation, single lab","pmids":["10964504"],"is_preprint":false},{"year":2000,"finding":"SHB binds the PDGF-α receptor via its SH2 domain at tyrosine 720 in the kinase insert domain; wild-type SHB overexpression (but not R522K mutant) reduces PDGF-induced membrane ruffle formation, stimulates filopodia, and diminishes Rac activation, indicating SHB regulates PDGF-dependent cytoskeletal organization through Rac.","method":"Co-immunoprecipitation, PDGF receptor Y→F mutants, overexpression of WT vs. R522K SHB, Rac activation assay, morphological analysis","journal":"Experimental cell research","confidence":"Medium","confidence_rationale":"Tier 2 — receptor binding mapped by mutagenesis, Rac activity assay, functional morphology readout","pmids":["10837138"],"is_preprint":false},{"year":2002,"finding":"The SHB SH2 domain binds FGFR-1 at tyrosine 766; overexpression of SH2-inactive SHB (R522K) dramatically reduces FGFR-1-mediated FRS2 phosphorylation and attenuates Ras/MEK/MAPK pathway activation and cell proliferation, placing SHB between FGFR-1 pY766 and FRS2 in mitogenic signaling.","method":"Chimeric receptor expression, Y766F mutation, GST-SH2 pulldown, dominant-negative overexpression, FRS2/MAPK Western blot, thymidine incorporation proliferation assay","journal":"Molecular biology of the cell","confidence":"High","confidence_rationale":"Tier 1/2 — receptor mutagenesis, dominant-negative, and multiple downstream pathway readouts in combination","pmids":["12181353"],"is_preprint":false},{"year":2002,"finding":"SHB links SLP-76, Gads, Vav, and ZAP70 with the TCR/CD3 complex in Jurkat T cells; SLP-76 and ZAP70 co-immunoprecipitate with SHB; SHB and Vav co-immunoprecipitate when co-transfected in COS cells; different domains of SHB independently bind SLP-76, Gads, and Vav; SH2-defective SHB reduces SLP-76/Vav phosphorylation and JNK activation; SHB localizes to lipid rafts/GEMs upon TCR stimulation.","method":"Co-immunoprecipitation, GST fusion protein pulldowns, dominant-negative overexpression, JNK kinase assay, lipid raft fractionation","journal":"European journal of biochemistry","confidence":"High","confidence_rationale":"Tier 2 — multiple co-IPs, domain mapping, functional consequence with dominant-negative, localization by biochemical fractionation","pmids":["12084069"],"is_preprint":false},{"year":2002,"finding":"SHB overexpression in RINm5F β-cells and primary islets increases basal IRS-1 tyrosine phosphorylation and assembles a multiunit complex containing SHB, IRS-1, IRS-2, FAK, and PI3K, leading to enhanced basal Akt phosphorylation and increased cell proliferation.","method":"Stable transfection, immunoprecipitation, in vitro kinase assay, Western blot for pAkt, flow cytometry for proliferation","journal":"Molecular medicine","confidence":"Medium","confidence_rationale":"Tier 2 — co-IP complex identification plus multiple downstream signaling readouts, single lab","pmids":["12520086"],"is_preprint":false},{"year":2002,"finding":"SHB overexpression in murine brain endothelial cells (IBE) increases apoptosis on serum withdrawal; both WT and R522K SHB induce spreading and cytoskeletal rearrangements via altered Rac1/Rap1 activation independent of PI3K but dependent on Src family kinases; SH2-mutant SHB (R522K) impairs FGF-2-induced tubular morphogenesis in collagen gels.","method":"Stable overexpression, Rac1/Rap1 activation assays, PI3K inhibitor treatment, Src inhibitor treatment, 3D collagen gel morphogenesis assay","journal":"Cell growth & differentiation","confidence":"Medium","confidence_rationale":"Tier 2 — multiple small GTPase activity assays and inhibitor dissection with defined morphogenesis readout","pmids":["11959815"],"is_preprint":false},{"year":2002,"finding":"IL-2 receptor β and γ subunits co-immunoprecipitate with SHB; the SHB SH2 domain binds phosphorylated Tyr-510 on IL-2Rβ; JAK1 and JAK3 associate with SHB proline-rich regions; SHB with functional SH2 domain promotes survival (reduced apoptosis) in the presence of IL-2, while SH2-mutant SHB or Y392F/Y510F IL-2Rβ mutant abrogates this effect.","method":"Co-immunoprecipitation in COS cells and primary T/NK cells, GST fusion protein binding, dominant-negative overexpression, apoptosis assay","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 — receptor binding site mapped plus functional anti-apoptotic consequence, single lab","pmids":["12200137"],"is_preprint":false},{"year":2003,"finding":"FGF-2 stimulation induces direct association between SHB and FAK mediated by the SHB PTB domain; SHB overexpression (WT or R522K) increases FAK phosphorylation and cell spreading on collagen; SHB tyrosine phosphorylation upon FGF-2 is Src-dependent but FAK-independent; active Src (tsLA29 v-Src) enhances SHB phosphorylation.","method":"Co-immunoprecipitation, PTB domain fusion pulldown, temperature-sensitive v-Src cells, Src inhibitor treatment, Western blot for FAK phosphorylation, spreading assay","journal":"Cellular signalling","confidence":"High","confidence_rationale":"Tier 2 — direct domain-mediated interaction demonstrated, confirmed with multiple cell systems and inhibitors","pmids":["12464388"],"is_preprint":false},{"year":2004,"finding":"SHB binds tyrosine 1175 in VEGFR-2 via its SH2 domain; SHB is phosphorylated in a Src-dependent manner upon VEGF stimulation; reduced SHB expression (siRNA) abolishes VEGF-induced PI3K stimulation, FAK phosphorylation at Y576, focal adhesion formation, stress fiber formation, and cell migration.","method":"GST-SH2 domain pulldown with VEGFR-2 peptides, co-immunoprecipitation, siRNA knockdown, PI3K assay, FAK/stress fiber immunofluorescence, migration assay","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1/2 — receptor binding site mapped by pulldown with mutagenesis, siRNA phenotype with multiple downstream readouts, highly cited","pmids":["15026417"],"is_preprint":false},{"year":2005,"finding":"SHB overexpression in embryonic stem cells promotes vascular structure outgrowth in embryoid bodies, increases VEGFR-2-positive cell numbers and PDGFR-β expression; SH2-mutant SHB (R522K) fails to support vascular structure formation, indicating SHB transduces VEGFR-2 and PDGFR-β signals for vascular differentiation.","method":"Stable ES cell transfection, embryoid body differentiation, CD31/VEGFR-2 immunostaining, real-time RT-PCR, PDGF-BB signaling inhibition, microarray","journal":"Experimental cell research","confidence":"Medium","confidence_rationale":"Tier 2 — SH2 mutagenesis with defined vascular differentiation readout, single lab","pmids":["15919073"],"is_preprint":false},{"year":2006,"finding":"SHB-/- embryoid bodies exhibit delayed down-regulation of Brachyury and reduced expression of hematopoietic, vascular, and cardiac lineage markers; SHB-/- ES cells form fewer blood cell colonies and show impaired blood vessel formation after VEGF stimulation, establishing SHB as required for mesoderm-to-hematopoietic/vascular differentiation.","method":"SHB knockout ES cell lines, embryoid body differentiation, gene expression by real-time RT-PCR, CD31 immunostaining, methylcellulose hematopoietic colony assay","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 — genetic knockout with multiple lineage differentiation readouts, single lab","pmids":["16971391"],"is_preprint":false},{"year":2006,"finding":"SHB interacts with c-Abl; tyrosine-phosphorylated SHB recruits c-Abl via concerted SH3 and SH2 domain interactions; SHB regulates c-Abl kinase activity; SHB/c-Abl interaction promotes hydrogen peroxide-induced cell death; SHB knockdown reduces c-Abl activity and alters cell death in response to cisplatin and tunicamycin.","method":"Co-immunoprecipitation, c-Abl kinase activity assay, overexpression, lentiviral shRNA knockdown, apoptosis assays","journal":"Experimental cell research","confidence":"Medium","confidence_rationale":"Tier 2 — co-IP plus kinase activity measurement plus KD rescue, single lab","pmids":["17112510"],"is_preprint":false},{"year":2007,"finding":"SHB associates with the EBV LMP2A N-terminal tail through both SH2 and PTB domain interactions with phosphorylated tyrosine motifs; shRNA-mediated SHB knockdown abolishes constitutive Akt activation in LMP2A-expressing cells; SHB-mediated binding to the LMP2A ITAM motif regulates Syk tyrosine kinase stability.","method":"Co-immunoprecipitation, domain-specific binding assays, shRNA knockdown, Western blot for pAkt and Syk","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 — domain mapping plus shRNA functional validation with defined signaling readouts, single lab","pmids":["17311000"],"is_preprint":false},{"year":2007,"finding":"SHB knockdown in SVR angiosarcoma endothelial cells increases susceptibility to cisplatin and staurosporine-induced apoptosis and reduces FAK phosphorylation at Y576/577, coinciding with an elongated cell phenotype; SHB knockdown cells show increased apoptosis and strongly reduced tumor growth in vivo upon honokiol treatment.","method":"Inducible lentiviral shRNA knockdown, Western blot for FAK phosphorylation, apoptosis assays, in vivo tumor growth","journal":"The Journal of investigative dermatology","confidence":"Medium","confidence_rationale":"Tier 2 — inducible KD with mechanistic (FAK) and phenotypic readouts in vitro and in vivo, single lab","pmids":["17914455"],"is_preprint":false},{"year":2009,"finding":"Shb knockout mice display dysfunctional endothelial ultrastructure (abnormal cytoplasmic extensions in liver sinusoids/heart capillaries), less distinct VE-cadherin staining, increased baseline vascular permeability in heart/kidney/skin, reduced VEGF-stimulated vascular permeability, and impaired tumor angiogenesis with retarded tumor growth.","method":"Shb knockout mouse, electron microscopy of endothelium, VE-cadherin immunostaining, vascular permeability assays, Matrigel plug angiogenesis, tumor implantation","journal":"Cancer research","confidence":"High","confidence_rationale":"Tier 2 — genetic knockout with multiple orthogonal vascular readouts, replicated across studies","pmids":["19223532"],"is_preprint":false},{"year":2009,"finding":"Shb-/- islets display blunted first-phase glucose-induced insulin secretion with dramatically reduced readily releasable granules (capacitance measurements), altered microvascular morphology with reduced islet capillary density, and elevated basal blood glucose; glucose-induced ATP generation and cytoplasmic Ca2+ are unaffected, implicating SHB in regulation of the exocytotic machinery.","method":"Pancreatic perfusion, patch-clamp capacitance measurements, Laser-Doppler blood flow, immunofluorescence of islet vasculature, glucose/insulin tolerance tests","journal":"The Journal of endocrinology","confidence":"High","confidence_rationale":"Tier 1/2 — patch-clamp electrophysiology (Tier 1) in genetic knockout plus multiple metabolic readouts","pmids":["19696098"],"is_preprint":false},{"year":2010,"finding":"SHB deficiency in mouse oocytes accelerates oogenesis, impairs follicle maturation, causes less synchronized meiosis I completion with premature polar body extrusion in some oocytes, impairs early embryo development after in vitro fertilization, and is associated with enhanced ERK and RSK signaling and increased ribosomal S6 phosphorylation in oocytes.","method":"Shb knockout mouse, oocyte staging, polar body extrusion assay, in vitro fertilization, Western blot for pERK/pRSK/pS6 in oocytes","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 — genetic knockout with oocyte-specific functional and signaling readouts, single lab","pmids":["20585392"],"is_preprint":false},{"year":2011,"finding":"Shb knockout T cells display increased basal TCR activation and reduced stimulation-induced phosphorylation, resulting in augmented peripheral CD4+ Th2 proliferation and elevated IL-4 production, establishing SHB as a modulator of TCR signal strength that controls Th1/Th2 balance.","method":"Shb knockout mouse, flow cytometry for T cell populations, TCR stimulation assays, intracellular cytokine staining, proliferation assay","journal":"BMC immunology","confidence":"Medium","confidence_rationale":"Tier 2 — genetic knockout with multiple immune cell functional readouts, single lab","pmids":["21223549"],"is_preprint":false},{"year":2012,"finding":"VEGF-A stimulation of wild-type endothelial cells causes dissociation of VE-cadherin from adherens junctions and decreases VE-cadherin/VEGFR-2 co-localization; in SHB-deficient endothelial cells, this response is absent and VEGFA fails to stimulate ERK, Akt, and Rac1, indicating SHB is required for proper VEGFR-2-to-VE-cadherin signaling that controls vascular permeability.","method":"Confocal and spinning-disk microscopy co-localization, SHB knockout primary lung endothelial cells, scratch wound assay, Western blot for pERK/pAkt, Rac1 pull-down assay","journal":"Cellular signalling","confidence":"Medium","confidence_rationale":"Tier 2 — live cell imaging co-localization plus multiple downstream signaling assays in knockout cells, single lab","pmids":["23000345"],"is_preprint":false},{"year":2012,"finding":"SHB knockout mice exhibit structural vascular abnormalities (increased arteriole frequency, irregular vasculature with fewer branch points and increased tortuosity in cremaster muscle, increased blood flow velocity) and functional defects: VEGF-A does not provoke VE-cadherin dissociation from adherens junctions, and reduced angiogenesis and vascular permeability impairs blood flow recovery after arterial ligation.","method":"Micro-CT angiography, intravital microscopy of cremaster, Matrigel plug assay, VE-cadherin immunostaining, femoral artery ligation with Laser-Doppler","journal":"Angiogenesis","confidence":"Medium","confidence_rationale":"Tier 2 — multiple in vivo vascular imaging and functional approaches in genetic knockout, single lab","pmids":["22562363"],"is_preprint":false},{"year":2012,"finding":"LMP2A phosphorylation promotes Shb and ITSN1 interaction: Shb simultaneously binds phosphorylated LMP2A tyrosines and ITSN1 SH3 domains, mediating indirect LMP2A-ITSN1 association; Syk kinase phosphorylates both ITSN1 and Shb in LMP2A-expressing cells, while Lyn additionally contributes to Shb phosphorylation.","method":"Co-immunoprecipitation, kinase inhibitor experiments (Syk, Lyn), Western blot for phosphoproteins","journal":"Cellular signalling","confidence":"Medium","confidence_rationale":"Tier 2 — co-IP with kinase inhibitor dissection, single lab","pmids":["22975684"],"is_preprint":false},{"year":2013,"finding":"SHB-deficient bone marrow contains fewer long-term hematopoietic stem cells (LT-HSCs) with lower proliferation rates; SHB knockout LT-HSCs exhibit elevated basal FAK/Rac1/PAK signaling and reduced responsiveness to Stem Cell Factor; FAK inhibitor treatment rescues LT-HSC proliferation in knockout mice, establishing SHB as a negative regulator of FAK activity controlling LT-HSC cell cycle.","method":"Flow cytometry of bone marrow populations, competitive transplantation, Western blot for FAK/Rac1/PAK, FAK inhibitor treatment, proliferation BrdU assay","journal":"Experimental cell research","confidence":"Medium","confidence_rationale":"Tier 2 — genetic knockout plus pharmacological rescue with defined signaling mechanism, single lab","pmids":["23528453"],"is_preprint":false},{"year":2014,"finding":"SHB deficiency in β-cells causes chronically elevated FAK activity, which delays glucose-induced cAMP rise (measured by live-cell FRET imaging of sub-membrane cAMP) and impairs insulin exocytosis; FAK inhibition increases sub-membrane cAMP, directly implicating elevated FAK in the secretory defect.","method":"Live-cell cAMP FRET imaging, patch-clamp capacitance measurements, immunoblotting, qPCR, FAK inhibitor treatment in Shb-knockout islets","journal":"The Journal of endocrinology","confidence":"High","confidence_rationale":"Tier 1 — live-cell imaging (Tier 1) plus electrophysiology plus pharmacological rescue, multiple orthogonal methods","pmids":["25274988"],"is_preprint":false},{"year":2014,"finding":"SHB knockout accelerates BCR-ABL-induced myeloproliferative leukemia due to elevated FAK activity in transformed bone marrow cells, which increases cytokine-independent colony formation; elevated IL-6 and G-CSF mRNA in knockout leukemic cells promotes peripheral neutrophilia; disease acceleration is intrinsic to leukemic cells and not solely niche-dependent.","method":"Retroviral BCR-ABL transformation, bone marrow transplantation, methylcellulose colony assay, flow cytometry, Western blot for FAK, qPCR for cytokines","journal":"Journal of hematology & oncology","confidence":"Medium","confidence_rationale":"Tier 2 — genetic model with transplantation controls and mechanistic (FAK) dissection, single lab","pmids":["24952416"],"is_preprint":false},{"year":2019,"finding":"VEGFA-induced co-localization of VEGFR2 with SHB occurs within <2.5 min and is dependent on VEGFR2 tyrosine 1175; SHB then enhances FAK co-localization with VEGFR2; in SHB-deficient endothelial cells FAK/VEGFR2 co-localization is reduced both basally and after VEGFA stimulation, and focal adhesion distribution is altered to a perinuclear location.","method":"TIRF (total internal reflection fluorescence) live-cell microscopy of co-localization dynamics, Y1175F-VEGFR2 mutant, SHB-deficient primary lung endothelial cells","journal":"Cells","confidence":"High","confidence_rationale":"Tier 1 — live TIRF imaging (Tier 1) with receptor mutagenesis and genetic knockout validation","pmids":["31847469"],"is_preprint":false},{"year":2020,"finding":"SHB is an essential scaffold for EphB2-mediated cell segregation; SHB interacts with Nck (via pY297), p120 RasGAP, and α/β-Chimaerin Rac GAPs (via pY246 and pY336 respectively) downstream of EphB2 (and EphA4, EphA8, EphB4); phosphorylation of SHB at Y297, Y246, and Y336 is required for EphB2-ephrinB1 boundary formation and cytoskeletal rearrangement.","method":"HEK293 EphB2+/ephrinB1+ cell segregation assay, co-immunoprecipitation, phosphospecific mutagenesis of SHB tyrosines, mass spectrometry interactome","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 — site-specific mutagenesis plus co-IP interactome plus functional cell segregation assay, multiple Eph receptors tested","pmids":["32060095"],"is_preprint":false},{"year":2020,"finding":"Conditional SHB inactivation in endothelial cells (Cdh5-CreERt2) reduces tumor growth, reduces vascular leakage, increases hypoxia, and alters adherens junction and focal adhesion gene expression in tumor endothelial cells; conditional SHB inactivation in pericytes (Pdgfrb-CreERt2) decreases pericyte coverage, increases vascular leakage, causes aberrant PDGFRB signaling, and increases lung metastasis without affecting tumor growth, establishing distinct roles of endothelial vs. pericyte SHB.","method":"Conditional cell-type-specific Cre-loxP knockout, tumor implantation, flow cytometry, immunofluorescence for vascular markers, RNAseq, vascular permeability assay","journal":"International journal of cancer","confidence":"High","confidence_rationale":"Tier 2 — cell-type-specific conditional knockouts with clear mechanistic dissection between two vascular compartments","pmids":["32441314"],"is_preprint":false}],"current_model":"SHB is a ubiquitously expressed scaffold/adaptor protein that recruits signaling complexes downstream of multiple receptor tyrosine kinases (VEGFR-2, FGFR-1, PDGFR, TrkA, EphB2, IL-2R, TCR) by binding phosphotyrosine motifs via its SH2 and PTB domains and proline-rich sequences via SH3 domain partners; through context-dependent assembly of complexes including FAK, PI3K, IRS-1/2, Rac1, Rap1, c-Abl, PLC-γ1, LAT, SLP-76, Vav, Nck, RasGAP, and Chimaerins, SHB regulates cell survival/apoptosis, migration, cytoskeletal organization, vascular permeability, angiogenesis, hematopoietic stem cell proliferation, T cell activation, and insulin secretion, with SHB phosphorylation at specific tyrosines (including Y1175 of VEGFR-2 as docking site, and Y246/Y297/Y336 of SHB itself for EphB2 signaling) being critical determinants of complex composition and downstream output."},"narrative":{"teleology":[{"year":1994,"claim":"Identification of SHB as a novel SH2-domain adaptor that selectively binds the autophosphorylated PDGF β-receptor established it as a new class of signaling scaffold linking RTKs to SH3-domain effectors.","evidence":"GST-SH2 pulldown, Western blot, cDNA cloning in fibroblasts","pmids":["8302579"],"confidence":"High","gaps":["No downstream signaling consequence demonstrated","Endogenous expression pattern not yet defined"]},{"year":1995,"claim":"Mapping the SH2 binding specificity (pY-T/V/I-X-L) and showing proline-rich motifs recruit Src, PI3K p85α, and Eps8 SH3 domains defined the modular logic by which SHB assembles multiprotein complexes.","evidence":"Degenerate phosphopeptide library, PDGFR Y→F mutants, GST-SH3 pulldowns, co-immunoprecipitation","pmids":["7537362"],"confidence":"High","gaps":["In vivo relevance of individual SH3 interactions not tested","PTB domain function not yet characterized"]},{"year":1996,"claim":"Demonstration that SHB overexpression induces apoptosis rescued by PDGF-BB but not IGF-1 provided the first evidence that SHB transduces receptor-specific survival/death signals.","evidence":"Stable NIH3T3 overexpression, TUNEL assay, growth factor rescue","pmids":["8806685"],"confidence":"Medium","gaps":["Overexpression artifact possible","Mechanism of apoptosis induction not defined"]},{"year":1998,"claim":"Discovery of SHB engagement with TCR ζ-chain via SH2, Grb2 via proline-rich motifs, and a novel PTB domain (binding Asp-Asp-X-pTyr) expanded SHB's receptor repertoire beyond RTKs to immune receptor signaling.","evidence":"Co-IP in Jurkat cells, phosphopeptide library for PTB, dominant-negative R522K mutant","pmids":["9484780"],"confidence":"High","gaps":["Identity of 36/38 kDa PTB-binding partner uncertain","Physiological T-cell phenotype not yet tested in vivo"]},{"year":1999,"claim":"Linking SHB to PLC-γ1, LAT phosphorylation, calcium flux, MAPK, and NFAT/IL-2 production downstream of TCR positioned SHB as a proximal organizer of T-cell activation signaling.","evidence":"Dominant-negative SHB in Jurkat cells, calcium imaging, NFAT reporter, IL-2 ELISA","pmids":["10488157"],"confidence":"High","gaps":["No loss-of-function in primary T cells yet","Mechanism of LAT phosphorylation regulation unclear"]},{"year":2000,"claim":"Multiple studies converged to show SHB regulates small GTPases Rac1 and Rap1 downstream of PDGFR, FGFR, and TrkA, controlling cytoskeletal organization, neurite outgrowth, and cell morphology — establishing Rac/Rap as core SHB effector axes.","evidence":"Rac1/Rap1 activity pulldowns, CrkII co-IP, PDGFR Y→F mutants, dominant-negative Rap1 approaches in NIH3T3, PC12, and IBE cells","pmids":["10837138","10878015","10964504"],"confidence":"Medium","gaps":["Direct versus indirect regulation of GTPases not resolved","Endogenous SHB loss-of-function not tested"]},{"year":2002,"claim":"SHB was shown to scaffold SLP-76, Vav, Gads, and ZAP70 at TCR lipid rafts, and separately to nucleate IRS-1/IRS-2/FAK/PI3K complexes in β-cells, demonstrating how SHB's multiple domains build tissue-specific signaling platforms.","evidence":"Co-IP domain mapping and lipid raft fractionation in Jurkat cells; co-IP and Akt phosphorylation in RINm5F β-cells","pmids":["12084069","12520086"],"confidence":"High","gaps":["Stoichiometry and dynamics of multiprotein complexes unknown","Structural basis for simultaneous multi-partner engagement absent"]},{"year":2002,"claim":"Mapping SHB SH2 domain binding to FGFR-1 Y766 and showing dominant-negative SHB blocks FRS2 phosphorylation and MAPK-dependent proliferation placed SHB as an intermediary between FGFR-1 and the Ras/MAPK cascade.","evidence":"Chimeric receptor with Y766F mutation, GST-SH2 pulldown, proliferation assay","pmids":["12181353"],"confidence":"High","gaps":["Whether SHB directly activates FRS2 or acts through a kinase intermediate not resolved"]},{"year":2003,"claim":"Identification of the PTB domain as the FAK-binding module and Src as the kinase phosphorylating SHB established the FAK–SHB–Src signaling node that recurs across many SHB functions.","evidence":"PTB domain fusion pulldown, temperature-sensitive v-Src cells, Src inhibitor, FAK phosphorylation blots","pmids":["12464388"],"confidence":"High","gaps":["Direct binding interface between PTB and FAK not structurally defined"]},{"year":2004,"claim":"Demonstrating that SHB SH2 domain docks on VEGFR-2 Y1175 and that SHB knockdown abolishes VEGF-induced PI3K, FAK phosphorylation, and endothelial migration established SHB as a critical mediator of VEGF signaling.","evidence":"GST-SH2 pulldown with VEGFR-2 peptides, siRNA in endothelial cells, PI3K assay, FAK/migration readouts","pmids":["15026417"],"confidence":"High","gaps":["In vivo vascular consequence not yet shown at this point"]},{"year":2009,"claim":"Shb knockout mice revealed that loss of SHB causes dysfunctional endothelial ultrastructure, increased baseline vascular permeability, reduced VEGF-stimulated permeability, and impaired tumor angiogenesis — providing the first in vivo validation of SHB's vascular functions.","evidence":"Shb global knockout, electron microscopy, vascular permeability assays, tumor implantation","pmids":["19223532"],"confidence":"High","gaps":["Endothelial-specific versus systemic contributions not separated"]},{"year":2009,"claim":"Patch-clamp capacitance measurements in Shb-null islets showed dramatically reduced readily releasable insulin granules despite normal Ca2+ handling, pinpointing SHB's role to the exocytotic machinery rather than stimulus-secretion coupling upstream of Ca2+.","evidence":"Patch-clamp electrophysiology, pancreatic perfusion, islet vascular imaging in knockout mice","pmids":["19696098"],"confidence":"High","gaps":["Molecular target in exocytotic machinery not identified","Relative contribution of vascular versus β-cell-intrinsic defects unclear"]},{"year":2013,"claim":"Finding that Shb-null LT-HSCs have constitutively elevated FAK/Rac1/PAK signaling and that FAK inhibition rescues their proliferation defect established SHB as a negative regulator of FAK in hematopoietic stem cells.","evidence":"Flow cytometry of bone marrow, competitive transplantation, FAK/Rac1 Western blots, FAK inhibitor rescue in knockout","pmids":["23528453"],"confidence":"Medium","gaps":["Mechanism by which SHB restrains FAK activity not defined","Whether this applies to all stem cell contexts unknown"]},{"year":2014,"claim":"Live-cell cAMP FRET imaging showed that chronically elevated FAK in Shb-null β-cells delays glucose-induced sub-membrane cAMP rise, causally linking FAK hyperactivation to the insulin secretion defect and resolving the downstream mechanism.","evidence":"cAMP FRET biosensor, patch-clamp, FAK inhibitor rescue in Shb-knockout islets","pmids":["25274988"],"confidence":"High","gaps":["How FAK suppresses cAMP generation molecularly is unknown","Whether FAK inhibition fully rescues secretion in vivo not tested"]},{"year":2019,"claim":"TIRF microscopy resolved the temporal sequence of VEGFR2–SHB–FAK co-localization at the plasma membrane (<2.5 min) and showed SHB is required for VEGFR2-dependent FAK recruitment to focal adhesions, providing the real-time spatial mechanism.","evidence":"TIRF live-cell imaging, Y1175F-VEGFR2 mutant, SHB-knockout primary endothelial cells","pmids":["31847469"],"confidence":"High","gaps":["Whether SHB directly bridges VEGFR2 and FAK or acts through intermediaries not resolved at the molecular level"]},{"year":2020,"claim":"Identification of SHB phosphotyrosines Y246, Y297, and Y336 as docking sites for Nck, RasGAP, and chimaerin Rac GAPs downstream of EphB2 revealed how SHB's own phosphorylation pattern encodes effector specificity for Eph-mediated cell segregation.","evidence":"Phosphospecific Y→F mutagenesis, mass spectrometry interactome, HEK293 cell segregation assay with multiple Eph receptors","pmids":["32060095"],"confidence":"High","gaps":["Structural basis for multi-site phosphorylation decoding unknown","In vivo Eph boundary phenotype in Shb knockout not tested"]},{"year":2020,"claim":"Cell-type-specific conditional knockouts separated endothelial SHB (controls vascular leakage and tumor angiogenesis) from pericyte SHB (controls pericyte coverage and metastatic dissemination), demonstrating compartmentalized functions within the vascular niche.","evidence":"Cdh5-CreERt2 and Pdgfrb-CreERt2 conditional Shb knockouts, tumor implantation, RNAseq, vascular permeability","pmids":["32441314"],"confidence":"High","gaps":["Downstream signaling pathways in pericytes not deeply characterized","Therapeutic relevance of targeting SHB in specific vascular compartments not established"]},{"year":null,"claim":"Key unresolved questions include the structural basis for simultaneous multi-domain engagement of distinct partners, the mechanism by which SHB restrains FAK kinase activity, and whether SHB phosphorylation codes are conserved across receptor contexts in vivo.","evidence":"","pmids":[],"confidence":"High","gaps":["No crystal or cryo-EM structure of SHB or its complexes","No systematic in vivo phosphosite mutant analysis across tissues","Mechanism by which SHB suppresses basal FAK activity remains undefined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[0,1,4,13,14,17,18,35]}],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[13,34]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[0,4]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0,1,6,12,18,28,35]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[4,6,13,16,27]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[19,20,26]},{"term_id":"R-HSA-5357801","term_label":"Programmed Cell Death","supporting_discovery_ids":[2,8,21,23]}],"complexes":[],"partners":["FAK","VEGFR2","FGFR1","PI3K","SLP76","VAV1","NCK","C-ABL"],"other_free_text":[]},"mechanistic_narrative":"SHB is a multi-domain scaffold/adaptor protein that couples diverse receptor tyrosine kinases to downstream signaling cascades controlling cell survival, migration, cytoskeletal remodeling, and exocytosis. Its SH2 domain docks onto phosphotyrosine residues of VEGFR-2 (Y1175), FGFR-1 (Y766), PDGFR-α (Y720), IL-2Rβ (Y510), TCR ζ-chain, and Eph receptors, while its PTB domain binds FAK and its proline-rich motifs recruit SH3-containing partners including Src, PI3K p85α, Grb2, and JAK1/3, thereby assembling context-dependent multiprotein complexes that activate PI3K/Akt, Rac1, Rap1, MAPK, and FAK pathways [PMID:7537362, PMID:15026417, PMID:9484780, PMID:12464388, PMID:32060095]. In vivo, Shb knockout mice exhibit defective VEGF-induced vascular permeability, impaired angiogenesis and tumor growth, reduced hematopoietic stem cell proliferation due to constitutively elevated FAK signaling, blunted first-phase insulin secretion from pancreatic β-cells, and skewed T-cell Th1/Th2 balance [PMID:19223532, PMID:23528453, PMID:25274988, PMID:19696098, PMID:21223549]. SHB phosphorylation at specific tyrosines (Y246, Y297, Y336) further dictates effector recruitment — for example recruiting Nck and chimaerin Rac GAPs downstream of EphB2 to drive cell boundary formation — establishing SHB as a phosphotyrosine-dependent signaling hub whose complex composition determines cellular output [PMID:32060095, PMID:32441314]."},"prefetch_data":{"uniprot":{"accession":"Q15464","full_name":"SH2 domain-containing adapter protein B","aliases":[],"length_aa":509,"mass_kda":55.0,"function":"Adapter protein which regulates several signal transduction cascades by linking activated receptors to downstream signaling components. May play a role in angiogenesis by regulating FGFR1, VEGFR2 and PDGFR signaling. May also play a role in T-cell antigen receptor/TCR signaling, interleukin-2 signaling, apoptosis and neuronal cells differentiation by mediating basic-FGF and NGF-induced signaling cascades. May also regulate IRS1 and IRS2 signaling in insulin-producing cells","subcellular_location":"Cytoplasm; Cell membrane","url":"https://www.uniprot.org/uniprotkb/Q15464/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/SHB","classification":"Not Classified","n_dependent_lines":6,"n_total_lines":1208,"dependency_fraction":0.004966887417218543},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/SHB","total_profiled":1310},"omim":[{"mim_id":"617313","title":"SH2 DOMAIN-CONTAINING ADAPTOR PROTEIN F; SHF","url":"https://www.omim.org/entry/617313"},{"mim_id":"610481","title":"SRC HOMOLOGY 2 DOMAIN-CONTAINING TRANSFORMING PROTEIN D; SHD","url":"https://www.omim.org/entry/610481"},{"mim_id":"606573","title":"FYN-RELATED SRC FAMILY TYROSINE KINASE; FRK","url":"https://www.omim.org/entry/606573"},{"mim_id":"600314","title":"SH2 DOMAIN-CONTAINING ADAPTOR PROTEIN B; SHB","url":"https://www.omim.org/entry/600314"},{"mim_id":"173490","title":"PLATELET-DERIVED GROWTH FACTOR RECEPTOR, ALPHA; PDGFRA","url":"https://www.omim.org/entry/173490"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Cytosol","reliability":"Supported"},{"location":"Nucleoplasm","reliability":"Additional"},{"location":"Cytoplasmic bodies","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in many","driving_tissues":[],"url":"https://www.proteinatlas.org/search/SHB"},"hgnc":{"alias_symbol":[],"prev_symbol":[]},"alphafold":{"accession":"Q15464","domains":[{"cath_id":"3.30.505.10","chopping":"404-502","consensus_level":"high","plddt":90.6436,"start":404,"end":502}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q15464","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q15464-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q15464-F1-predicted_aligned_error_v6.png","plddt_mean":58.75},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=SHB","jax_strain_url":"https://www.jax.org/strain/search?query=SHB"},"sequence":{"accession":"Q15464","fasta_url":"https://rest.uniprot.org/uniprotkb/Q15464.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q15464/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q15464"}},"corpus_meta":[{"pmid":"10828022","id":"PMC_10828022","title":"Endostatin-induced tyrosine kinase signaling through the Shb adaptor protein regulates endothelial cell apoptosis.","date":"2000","source":"Blood","url":"https://pubmed.ncbi.nlm.nih.gov/10828022","citation_count":242,"is_preprint":false},{"pmid":"15026417","id":"PMC_15026417","title":"The adaptor protein shb binds to tyrosine 1175 in vascular endothelial growth factor (VEGF) receptor-2 and regulates VEGF-dependent cellular migration.","date":"2004","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/15026417","citation_count":205,"is_preprint":false},{"pmid":"12181353","id":"PMC_12181353","title":"The Shb adaptor protein binds to tyrosine 766 in the FGFR-1 and regulates the Ras/MEK/MAPK pathway via FRS2 phosphorylation in endothelial cells.","date":"2002","source":"Molecular biology of the cell","url":"https://pubmed.ncbi.nlm.nih.gov/12181353","citation_count":76,"is_preprint":false},{"pmid":"8302579","id":"PMC_8302579","title":"Shb is a ubiquitously expressed Src homology 2 protein.","date":"1994","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/8302579","citation_count":66,"is_preprint":false},{"pmid":"7537362","id":"PMC_7537362","title":"Molecular interactions of the Src homology 2 domain protein Shb with phosphotyrosine residues, tyrosine kinase receptors and Src homology 3 domain proteins.","date":"1995","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/7537362","citation_count":57,"is_preprint":false},{"pmid":"9484780","id":"PMC_9484780","title":"Stimulation through the T cell receptor leads to interactions between SHB and several signaling proteins.","date":"1998","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/9484780","citation_count":52,"is_preprint":false},{"pmid":"12776987","id":"PMC_12776987","title":"The FRK/RAK-SHB signaling cascade: a versatile signal-transduction pathway that regulates cell survival, differentiation and proliferation.","date":"2003","source":"Current molecular medicine","url":"https://pubmed.ncbi.nlm.nih.gov/12776987","citation_count":51,"is_preprint":false},{"pmid":"10488157","id":"PMC_10488157","title":"Requirement of the Src homology 2 domain protein Shb for T cell receptor-dependent activation of the interleukin-2 gene nuclear factor for activation of T cells element in Jurkat T cells.","date":"1999","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/10488157","citation_count":35,"is_preprint":false},{"pmid":"2484347","id":"PMC_2484347","title":"Properties of ShB A-type potassium channels expressed in Shaker mutant Drosophila by germline transformation.","date":"1989","source":"Neuron","url":"https://pubmed.ncbi.nlm.nih.gov/2484347","citation_count":34,"is_preprint":false},{"pmid":"10878015","id":"PMC_10878015","title":"GTK, a Src-related tyrosine kinase, induces nerve growth factor-independent neurite outgrowth in PC12 cells through activation of the Rap1 pathway. 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hematology","url":"https://pubmed.ncbi.nlm.nih.gov/9034293","citation_count":6,"is_preprint":false},{"pmid":"29792386","id":"PMC_29792386","title":"Disparate effects of Shb gene deficiency on disease characteristics in murine models of myeloid, B-cell, and T-cell leukemia.","date":"2018","source":"Tumour biology : the journal of the International Society for Oncodevelopmental Biology and Medicine","url":"https://pubmed.ncbi.nlm.nih.gov/29792386","citation_count":4,"is_preprint":false},{"pmid":"36220452","id":"PMC_36220452","title":"Sulfhemoglobin under the spotlight - Detection and characterization of SHb and HbFeIII-SH.","date":"2022","source":"Biochimica et biophysica acta. Molecular cell research","url":"https://pubmed.ncbi.nlm.nih.gov/36220452","citation_count":3,"is_preprint":false},{"pmid":"25274988","id":"PMC_25274988","title":"Absence of Shb impairs insulin secretion by elevated FAK activity in pancreatic islets.","date":"2014","source":"The Journal of endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/25274988","citation_count":3,"is_preprint":false},{"pmid":"29194461","id":"PMC_29194461","title":"Evaluation and validation of commercial antibodies for the detection of Shb.","date":"2017","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/29194461","citation_count":2,"is_preprint":false},{"pmid":"35243949","id":"PMC_35243949","title":"Profiling of 35 Cases of Hb S/Hb E (HBB: c.20A>T/HBB: c.79G>a), Disease and Association with α-Thalassemia and β-Globin Gene Cluster Haplotypes from Odisha, India.","date":"2022","source":"Hemoglobin","url":"https://pubmed.ncbi.nlm.nih.gov/35243949","citation_count":2,"is_preprint":false},{"pmid":"2097263","id":"PMC_2097263","title":"Unusual sickle cell disease observed for the first time in Italy: Hb S-Hb D Los Angeles.","date":"1990","source":"Haematologica","url":"https://pubmed.ncbi.nlm.nih.gov/2097263","citation_count":2,"is_preprint":false},{"pmid":"16846036","id":"PMC_16846036","title":"The role of the adapter protein SHB in embryonic stem cell differentiation into the pancreatic beta-cell and endothelial lineages.","date":"2006","source":"Methods in molecular biology (Clifton, N.J.)","url":"https://pubmed.ncbi.nlm.nih.gov/16846036","citation_count":1,"is_preprint":false},{"pmid":"33220260","id":"PMC_33220260","title":"Absence of the Shb gene in mixed-lineage leukemia MLL-AF9 cells increases latency in mice despite higher proliferation rates in vitro.","date":"2020","source":"Experimental cell research","url":"https://pubmed.ncbi.nlm.nih.gov/33220260","citation_count":0,"is_preprint":false},{"pmid":"38307823","id":"PMC_38307823","title":"Functional characterization of compound heterozygosity Hb S/Hb Deer Lodge in Brazil.","date":"2023","source":"Hematology, transfusion and cell therapy","url":"https://pubmed.ncbi.nlm.nih.gov/38307823","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.09.21.677623","title":"Anaerobic gut fungi <i>Caecomyces communis, Neocallimastix frontalis</i> and <i>Piromyces spp. nov.</i>, have distinct effects on plant fibres during digestion","date":"2025-09-21","source":"bioRxiv","url":"https://doi.org/10.1101/2025.09.21.677623","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.11.17.688593","title":"Rice NH2 Functions as a Positive Regulator of Salicylic Acid–Mediated Defense Responses Against Sheath Blight and Bacterial Blight","date":"2025-11-18","source":"bioRxiv","url":"https://doi.org/10.1101/2025.11.17.688593","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":34389,"output_tokens":9448,"usd":0.122443},"stage2":{"model":"claude-opus-4-6","input_tokens":13324,"output_tokens":4036,"usd":0.25128},"total_usd":0.373723,"stage1_batch_id":"msgbatch_011rkcQdVV1RaFq9XhcG6df6","stage2_batch_id":"msgbatch_01RzgrJafdF4EWHhj5mNi6dh","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1994,\n      \"finding\": \"SHB was identified as a novel SH2 domain-containing adaptor protein with proline-rich domains; its SH2 domain fusion protein binds the autophosphorylated PDGF β-receptor but not the EGF receptor, establishing SHB as a signal transduction adaptor linking SH3 domain proteins to tyrosine kinase receptors.\",\n      \"method\": \"GST-SH2 fusion protein pulldown, Western blot, cDNA cloning and transient/stable transfection\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — foundational characterization with multiple orthogonal methods (pulldown, immunoblot, transfection), replicated in subsequent studies\",\n      \"pmids\": [\"8302579\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1995,\n      \"finding\": \"The SHB SH2 domain preferentially binds the phosphopeptide motif pTyr-Thr/Val/Ile-X-Leu; it binds multiple autophosphorylation sites on the PDGF β-receptor and phosphorylated FGFR-1 (mainly via Y776); the proline-rich motifs (pro-4/pro-5) bind Src, p85α PI3-kinase, and Eps8 SH3 domains in vitro, and in vivo association with v-Src and Eps8 was confirmed by co-immunoprecipitation.\",\n      \"method\": \"Degenerate phosphopeptide library screening, competing peptides with PDGF receptor Y→F mutants, GST-SH3 fusion protein pulldowns, co-immunoprecipitation\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — in vitro binding assays with mutagenesis plus co-IP validation, multiple orthogonal approaches\",\n      \"pmids\": [\"7537362\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1996,\n      \"finding\": \"Overexpression of SHB in NIH3T3 fibroblasts causes apoptosis (pyknotic nuclei by TUNEL) under low-serum conditions, which is rescued by PDGF-BB but not IGF-1, establishing SHB as a mediator of apoptotic signaling downstream of specific tyrosine kinase receptors.\",\n      \"method\": \"Stable transfection, TUNEL staining, cell counting, PDGF/IGF-1 rescue experiments\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — clean overexpression with defined phenotypic readout (apoptosis), single lab\",\n      \"pmids\": [\"8806685\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1997,\n      \"finding\": \"SHB overexpression in NIH3T3 cells downregulates Eps8 protein and mRNA, increases basal PI3-kinase activity, and elevates STAT1 mRNA and protein levels, indicating that SHB modulates expression and activity of SH3 domain signaling proteins.\",\n      \"method\": \"Western blot, Northern blot, in vitro PI3-kinase assay in SHB-overexpressing cells\",\n      \"journal\": \"Experimental cell research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 — overexpression correlation with signaling changes, single lab, single approach per readout\",\n      \"pmids\": [\"9087167\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1998,\n      \"finding\": \"SHB is expressed in Jurkat T cells and, upon TCR stimulation, forms multiprotein complexes: Grb2 binds SHB proline-rich motifs via its SH3 domains; the SHB SH2 domain associates with the TCR ζ-chain (p22); a central PTB domain (preferring Asp-Asp-X-pTyr) binds p36/38 (possibly Lnk); overexpression of SHB increases basal phosphorylation of associated proteins, and the R522K SH2-inactive mutant reduces CD3-stimulated tyrosine phosphorylation.\",\n      \"method\": \"Co-immunoprecipitation, phosphopeptide library, dominant-negative mutant overexpression, Western blot\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods (co-IP, peptide library, mutagenesis), replicated in subsequent TCR papers\",\n      \"pmids\": [\"9484780\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1998,\n      \"finding\": \"SHB overexpression in PC12 cells enhances NGF- and bFGF-induced neurite outgrowth in an SH2 domain-dependent manner; SHB is tyrosine phosphorylated and co-immunoprecipitates with a 140 kDa phosphotyrosine protein upon NGF treatment, placing SHB downstream of TrkA/FGFR in neuronal differentiation signaling.\",\n      \"method\": \"Stable transfection, neurite outgrowth assay, immunoprecipitation, Western blot\",\n      \"journal\": \"Cell growth & differentiation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — SH2 domain mutagenesis plus co-IP, clean cellular phenotype readout, single lab\",\n      \"pmids\": [\"9751119\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1999,\n      \"finding\": \"SHB associates with PLC-γ1 in Jurkat T cells; expression of SH2-defective SHB diminishes LAT phosphorylation, blocks PLC-γ1 phosphorylation, abolishes calcium rise, suppresses MAPK activation, prevents NFAT activation, and reduces endogenous IL-2 production upon TCR stimulation.\",\n      \"method\": \"Co-immunoprecipitation, dominant-negative overexpression, calcium imaging, NFAT reporter assay, cytokine ELISA\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple downstream readouts with dominant-negative mutant, mechanistic pathway placement\",\n      \"pmids\": [\"10488157\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1999,\n      \"finding\": \"Transgenic mice overexpressing SHB in β-cells (under rat insulin promoter) show increased β-cell area, enhanced glucose-stimulated insulin secretion, higher islet DNA content, and elevated apoptosis under cytokine or low-serum stress, establishing a dual role for SHB in β-cell proliferation and death.\",\n      \"method\": \"Transgenic mouse generation, glucose tolerance test, islet isolation, insulin secretion assay, TUNEL staining\",\n      \"journal\": \"Molecular medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — in vivo transgenic model with multiple functional readouts, single lab\",\n      \"pmids\": [\"10404514\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"Endostatin induces tyrosine phosphorylation of SHB and formation of multiprotein complexes in endothelial cells; the SHB SH2 domain pull-down co-precipitates a 125 kDa phosphotyrosyl protein with intrinsic or associated tyrosine kinase activity; SHB overexpression in IBE cells enhances endostatin-induced apoptosis in an SH2 domain- and endostatin heparin-binding-dependent manner.\",\n      \"method\": \"Western blot for pTyr-SHB, SH2 domain fusion protein pulldown, overexpression with SH2 mutant, apoptosis assays\",\n      \"journal\": \"Blood\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods (pulldown, co-IP, mutagenesis, functional apoptosis assay), highly cited\",\n      \"pmids\": [\"10828022\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"GTK (FRK/RAK) overexpression in PC12 cells causes increased FAK content, phosphorylation of SHB, and association between SHB and FAK; this correlates with CrkII complex formation with p130Cas, FAK and SHB, and Rap1 activation required for neurite outgrowth, placing SHB downstream of GTK in a FAK/CrkII/Rap1 pathway.\",\n      \"method\": \"Western blot, co-immunoprecipitation, Rap1 activity assay (RalGDS-RBD pulldown), dominant-negative transfection, neurite outgrowth assay\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — co-IP plus functional pathway validation with dominant negatives, single lab\",\n      \"pmids\": [\"10878015\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"SHB overexpression in PC12 cells enables NGF- and EGF- (but not FGF-2-) induced Rap1 activation in an SH2 domain-dependent manner; CrkII SH2 domain interacts with SHB and a 130-135 kDa phosphotyrosine protein; blocking Rap1 signaling (RalGDS-RBD or Rap1GAP) reduces SHB-dependent neurite outgrowth.\",\n      \"method\": \"Rap1 activity assay, co-immunoprecipitation, dominant-negative transfection, neurite outgrowth assay\",\n      \"journal\": \"Experimental cell research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — Rap1 pull-down activity assay plus functional pathway validation, single lab\",\n      \"pmids\": [\"10964504\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"SHB binds the PDGF-α receptor via its SH2 domain at tyrosine 720 in the kinase insert domain; wild-type SHB overexpression (but not R522K mutant) reduces PDGF-induced membrane ruffle formation, stimulates filopodia, and diminishes Rac activation, indicating SHB regulates PDGF-dependent cytoskeletal organization through Rac.\",\n      \"method\": \"Co-immunoprecipitation, PDGF receptor Y→F mutants, overexpression of WT vs. R522K SHB, Rac activation assay, morphological analysis\",\n      \"journal\": \"Experimental cell research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — receptor binding mapped by mutagenesis, Rac activity assay, functional morphology readout\",\n      \"pmids\": [\"10837138\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"The SHB SH2 domain binds FGFR-1 at tyrosine 766; overexpression of SH2-inactive SHB (R522K) dramatically reduces FGFR-1-mediated FRS2 phosphorylation and attenuates Ras/MEK/MAPK pathway activation and cell proliferation, placing SHB between FGFR-1 pY766 and FRS2 in mitogenic signaling.\",\n      \"method\": \"Chimeric receptor expression, Y766F mutation, GST-SH2 pulldown, dominant-negative overexpression, FRS2/MAPK Western blot, thymidine incorporation proliferation assay\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1/2 — receptor mutagenesis, dominant-negative, and multiple downstream pathway readouts in combination\",\n      \"pmids\": [\"12181353\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"SHB links SLP-76, Gads, Vav, and ZAP70 with the TCR/CD3 complex in Jurkat T cells; SLP-76 and ZAP70 co-immunoprecipitate with SHB; SHB and Vav co-immunoprecipitate when co-transfected in COS cells; different domains of SHB independently bind SLP-76, Gads, and Vav; SH2-defective SHB reduces SLP-76/Vav phosphorylation and JNK activation; SHB localizes to lipid rafts/GEMs upon TCR stimulation.\",\n      \"method\": \"Co-immunoprecipitation, GST fusion protein pulldowns, dominant-negative overexpression, JNK kinase assay, lipid raft fractionation\",\n      \"journal\": \"European journal of biochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple co-IPs, domain mapping, functional consequence with dominant-negative, localization by biochemical fractionation\",\n      \"pmids\": [\"12084069\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"SHB overexpression in RINm5F β-cells and primary islets increases basal IRS-1 tyrosine phosphorylation and assembles a multiunit complex containing SHB, IRS-1, IRS-2, FAK, and PI3K, leading to enhanced basal Akt phosphorylation and increased cell proliferation.\",\n      \"method\": \"Stable transfection, immunoprecipitation, in vitro kinase assay, Western blot for pAkt, flow cytometry for proliferation\",\n      \"journal\": \"Molecular medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — co-IP complex identification plus multiple downstream signaling readouts, single lab\",\n      \"pmids\": [\"12520086\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"SHB overexpression in murine brain endothelial cells (IBE) increases apoptosis on serum withdrawal; both WT and R522K SHB induce spreading and cytoskeletal rearrangements via altered Rac1/Rap1 activation independent of PI3K but dependent on Src family kinases; SH2-mutant SHB (R522K) impairs FGF-2-induced tubular morphogenesis in collagen gels.\",\n      \"method\": \"Stable overexpression, Rac1/Rap1 activation assays, PI3K inhibitor treatment, Src inhibitor treatment, 3D collagen gel morphogenesis assay\",\n      \"journal\": \"Cell growth & differentiation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — multiple small GTPase activity assays and inhibitor dissection with defined morphogenesis readout\",\n      \"pmids\": [\"11959815\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"IL-2 receptor β and γ subunits co-immunoprecipitate with SHB; the SHB SH2 domain binds phosphorylated Tyr-510 on IL-2Rβ; JAK1 and JAK3 associate with SHB proline-rich regions; SHB with functional SH2 domain promotes survival (reduced apoptosis) in the presence of IL-2, while SH2-mutant SHB or Y392F/Y510F IL-2Rβ mutant abrogates this effect.\",\n      \"method\": \"Co-immunoprecipitation in COS cells and primary T/NK cells, GST fusion protein binding, dominant-negative overexpression, apoptosis assay\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — receptor binding site mapped plus functional anti-apoptotic consequence, single lab\",\n      \"pmids\": [\"12200137\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"FGF-2 stimulation induces direct association between SHB and FAK mediated by the SHB PTB domain; SHB overexpression (WT or R522K) increases FAK phosphorylation and cell spreading on collagen; SHB tyrosine phosphorylation upon FGF-2 is Src-dependent but FAK-independent; active Src (tsLA29 v-Src) enhances SHB phosphorylation.\",\n      \"method\": \"Co-immunoprecipitation, PTB domain fusion pulldown, temperature-sensitive v-Src cells, Src inhibitor treatment, Western blot for FAK phosphorylation, spreading assay\",\n      \"journal\": \"Cellular signalling\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — direct domain-mediated interaction demonstrated, confirmed with multiple cell systems and inhibitors\",\n      \"pmids\": [\"12464388\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"SHB binds tyrosine 1175 in VEGFR-2 via its SH2 domain; SHB is phosphorylated in a Src-dependent manner upon VEGF stimulation; reduced SHB expression (siRNA) abolishes VEGF-induced PI3K stimulation, FAK phosphorylation at Y576, focal adhesion formation, stress fiber formation, and cell migration.\",\n      \"method\": \"GST-SH2 domain pulldown with VEGFR-2 peptides, co-immunoprecipitation, siRNA knockdown, PI3K assay, FAK/stress fiber immunofluorescence, migration assay\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1/2 — receptor binding site mapped by pulldown with mutagenesis, siRNA phenotype with multiple downstream readouts, highly cited\",\n      \"pmids\": [\"15026417\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"SHB overexpression in embryonic stem cells promotes vascular structure outgrowth in embryoid bodies, increases VEGFR-2-positive cell numbers and PDGFR-β expression; SH2-mutant SHB (R522K) fails to support vascular structure formation, indicating SHB transduces VEGFR-2 and PDGFR-β signals for vascular differentiation.\",\n      \"method\": \"Stable ES cell transfection, embryoid body differentiation, CD31/VEGFR-2 immunostaining, real-time RT-PCR, PDGF-BB signaling inhibition, microarray\",\n      \"journal\": \"Experimental cell research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — SH2 mutagenesis with defined vascular differentiation readout, single lab\",\n      \"pmids\": [\"15919073\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"SHB-/- embryoid bodies exhibit delayed down-regulation of Brachyury and reduced expression of hematopoietic, vascular, and cardiac lineage markers; SHB-/- ES cells form fewer blood cell colonies and show impaired blood vessel formation after VEGF stimulation, establishing SHB as required for mesoderm-to-hematopoietic/vascular differentiation.\",\n      \"method\": \"SHB knockout ES cell lines, embryoid body differentiation, gene expression by real-time RT-PCR, CD31 immunostaining, methylcellulose hematopoietic colony assay\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — genetic knockout with multiple lineage differentiation readouts, single lab\",\n      \"pmids\": [\"16971391\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"SHB interacts with c-Abl; tyrosine-phosphorylated SHB recruits c-Abl via concerted SH3 and SH2 domain interactions; SHB regulates c-Abl kinase activity; SHB/c-Abl interaction promotes hydrogen peroxide-induced cell death; SHB knockdown reduces c-Abl activity and alters cell death in response to cisplatin and tunicamycin.\",\n      \"method\": \"Co-immunoprecipitation, c-Abl kinase activity assay, overexpression, lentiviral shRNA knockdown, apoptosis assays\",\n      \"journal\": \"Experimental cell research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — co-IP plus kinase activity measurement plus KD rescue, single lab\",\n      \"pmids\": [\"17112510\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"SHB associates with the EBV LMP2A N-terminal tail through both SH2 and PTB domain interactions with phosphorylated tyrosine motifs; shRNA-mediated SHB knockdown abolishes constitutive Akt activation in LMP2A-expressing cells; SHB-mediated binding to the LMP2A ITAM motif regulates Syk tyrosine kinase stability.\",\n      \"method\": \"Co-immunoprecipitation, domain-specific binding assays, shRNA knockdown, Western blot for pAkt and Syk\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — domain mapping plus shRNA functional validation with defined signaling readouts, single lab\",\n      \"pmids\": [\"17311000\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"SHB knockdown in SVR angiosarcoma endothelial cells increases susceptibility to cisplatin and staurosporine-induced apoptosis and reduces FAK phosphorylation at Y576/577, coinciding with an elongated cell phenotype; SHB knockdown cells show increased apoptosis and strongly reduced tumor growth in vivo upon honokiol treatment.\",\n      \"method\": \"Inducible lentiviral shRNA knockdown, Western blot for FAK phosphorylation, apoptosis assays, in vivo tumor growth\",\n      \"journal\": \"The Journal of investigative dermatology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — inducible KD with mechanistic (FAK) and phenotypic readouts in vitro and in vivo, single lab\",\n      \"pmids\": [\"17914455\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"Shb knockout mice display dysfunctional endothelial ultrastructure (abnormal cytoplasmic extensions in liver sinusoids/heart capillaries), less distinct VE-cadherin staining, increased baseline vascular permeability in heart/kidney/skin, reduced VEGF-stimulated vascular permeability, and impaired tumor angiogenesis with retarded tumor growth.\",\n      \"method\": \"Shb knockout mouse, electron microscopy of endothelium, VE-cadherin immunostaining, vascular permeability assays, Matrigel plug angiogenesis, tumor implantation\",\n      \"journal\": \"Cancer research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — genetic knockout with multiple orthogonal vascular readouts, replicated across studies\",\n      \"pmids\": [\"19223532\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"Shb-/- islets display blunted first-phase glucose-induced insulin secretion with dramatically reduced readily releasable granules (capacitance measurements), altered microvascular morphology with reduced islet capillary density, and elevated basal blood glucose; glucose-induced ATP generation and cytoplasmic Ca2+ are unaffected, implicating SHB in regulation of the exocytotic machinery.\",\n      \"method\": \"Pancreatic perfusion, patch-clamp capacitance measurements, Laser-Doppler blood flow, immunofluorescence of islet vasculature, glucose/insulin tolerance tests\",\n      \"journal\": \"The Journal of endocrinology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1/2 — patch-clamp electrophysiology (Tier 1) in genetic knockout plus multiple metabolic readouts\",\n      \"pmids\": [\"19696098\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"SHB deficiency in mouse oocytes accelerates oogenesis, impairs follicle maturation, causes less synchronized meiosis I completion with premature polar body extrusion in some oocytes, impairs early embryo development after in vitro fertilization, and is associated with enhanced ERK and RSK signaling and increased ribosomal S6 phosphorylation in oocytes.\",\n      \"method\": \"Shb knockout mouse, oocyte staging, polar body extrusion assay, in vitro fertilization, Western blot for pERK/pRSK/pS6 in oocytes\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — genetic knockout with oocyte-specific functional and signaling readouts, single lab\",\n      \"pmids\": [\"20585392\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Shb knockout T cells display increased basal TCR activation and reduced stimulation-induced phosphorylation, resulting in augmented peripheral CD4+ Th2 proliferation and elevated IL-4 production, establishing SHB as a modulator of TCR signal strength that controls Th1/Th2 balance.\",\n      \"method\": \"Shb knockout mouse, flow cytometry for T cell populations, TCR stimulation assays, intracellular cytokine staining, proliferation assay\",\n      \"journal\": \"BMC immunology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — genetic knockout with multiple immune cell functional readouts, single lab\",\n      \"pmids\": [\"21223549\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"VEGF-A stimulation of wild-type endothelial cells causes dissociation of VE-cadherin from adherens junctions and decreases VE-cadherin/VEGFR-2 co-localization; in SHB-deficient endothelial cells, this response is absent and VEGFA fails to stimulate ERK, Akt, and Rac1, indicating SHB is required for proper VEGFR-2-to-VE-cadherin signaling that controls vascular permeability.\",\n      \"method\": \"Confocal and spinning-disk microscopy co-localization, SHB knockout primary lung endothelial cells, scratch wound assay, Western blot for pERK/pAkt, Rac1 pull-down assay\",\n      \"journal\": \"Cellular signalling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — live cell imaging co-localization plus multiple downstream signaling assays in knockout cells, single lab\",\n      \"pmids\": [\"23000345\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"SHB knockout mice exhibit structural vascular abnormalities (increased arteriole frequency, irregular vasculature with fewer branch points and increased tortuosity in cremaster muscle, increased blood flow velocity) and functional defects: VEGF-A does not provoke VE-cadherin dissociation from adherens junctions, and reduced angiogenesis and vascular permeability impairs blood flow recovery after arterial ligation.\",\n      \"method\": \"Micro-CT angiography, intravital microscopy of cremaster, Matrigel plug assay, VE-cadherin immunostaining, femoral artery ligation with Laser-Doppler\",\n      \"journal\": \"Angiogenesis\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — multiple in vivo vascular imaging and functional approaches in genetic knockout, single lab\",\n      \"pmids\": [\"22562363\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"LMP2A phosphorylation promotes Shb and ITSN1 interaction: Shb simultaneously binds phosphorylated LMP2A tyrosines and ITSN1 SH3 domains, mediating indirect LMP2A-ITSN1 association; Syk kinase phosphorylates both ITSN1 and Shb in LMP2A-expressing cells, while Lyn additionally contributes to Shb phosphorylation.\",\n      \"method\": \"Co-immunoprecipitation, kinase inhibitor experiments (Syk, Lyn), Western blot for phosphoproteins\",\n      \"journal\": \"Cellular signalling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — co-IP with kinase inhibitor dissection, single lab\",\n      \"pmids\": [\"22975684\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"SHB-deficient bone marrow contains fewer long-term hematopoietic stem cells (LT-HSCs) with lower proliferation rates; SHB knockout LT-HSCs exhibit elevated basal FAK/Rac1/PAK signaling and reduced responsiveness to Stem Cell Factor; FAK inhibitor treatment rescues LT-HSC proliferation in knockout mice, establishing SHB as a negative regulator of FAK activity controlling LT-HSC cell cycle.\",\n      \"method\": \"Flow cytometry of bone marrow populations, competitive transplantation, Western blot for FAK/Rac1/PAK, FAK inhibitor treatment, proliferation BrdU assay\",\n      \"journal\": \"Experimental cell research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — genetic knockout plus pharmacological rescue with defined signaling mechanism, single lab\",\n      \"pmids\": [\"23528453\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"SHB deficiency in β-cells causes chronically elevated FAK activity, which delays glucose-induced cAMP rise (measured by live-cell FRET imaging of sub-membrane cAMP) and impairs insulin exocytosis; FAK inhibition increases sub-membrane cAMP, directly implicating elevated FAK in the secretory defect.\",\n      \"method\": \"Live-cell cAMP FRET imaging, patch-clamp capacitance measurements, immunoblotting, qPCR, FAK inhibitor treatment in Shb-knockout islets\",\n      \"journal\": \"The Journal of endocrinology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — live-cell imaging (Tier 1) plus electrophysiology plus pharmacological rescue, multiple orthogonal methods\",\n      \"pmids\": [\"25274988\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"SHB knockout accelerates BCR-ABL-induced myeloproliferative leukemia due to elevated FAK activity in transformed bone marrow cells, which increases cytokine-independent colony formation; elevated IL-6 and G-CSF mRNA in knockout leukemic cells promotes peripheral neutrophilia; disease acceleration is intrinsic to leukemic cells and not solely niche-dependent.\",\n      \"method\": \"Retroviral BCR-ABL transformation, bone marrow transplantation, methylcellulose colony assay, flow cytometry, Western blot for FAK, qPCR for cytokines\",\n      \"journal\": \"Journal of hematology & oncology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — genetic model with transplantation controls and mechanistic (FAK) dissection, single lab\",\n      \"pmids\": [\"24952416\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"VEGFA-induced co-localization of VEGFR2 with SHB occurs within <2.5 min and is dependent on VEGFR2 tyrosine 1175; SHB then enhances FAK co-localization with VEGFR2; in SHB-deficient endothelial cells FAK/VEGFR2 co-localization is reduced both basally and after VEGFA stimulation, and focal adhesion distribution is altered to a perinuclear location.\",\n      \"method\": \"TIRF (total internal reflection fluorescence) live-cell microscopy of co-localization dynamics, Y1175F-VEGFR2 mutant, SHB-deficient primary lung endothelial cells\",\n      \"journal\": \"Cells\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — live TIRF imaging (Tier 1) with receptor mutagenesis and genetic knockout validation\",\n      \"pmids\": [\"31847469\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"SHB is an essential scaffold for EphB2-mediated cell segregation; SHB interacts with Nck (via pY297), p120 RasGAP, and α/β-Chimaerin Rac GAPs (via pY246 and pY336 respectively) downstream of EphB2 (and EphA4, EphA8, EphB4); phosphorylation of SHB at Y297, Y246, and Y336 is required for EphB2-ephrinB1 boundary formation and cytoskeletal rearrangement.\",\n      \"method\": \"HEK293 EphB2+/ephrinB1+ cell segregation assay, co-immunoprecipitation, phosphospecific mutagenesis of SHB tyrosines, mass spectrometry interactome\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — site-specific mutagenesis plus co-IP interactome plus functional cell segregation assay, multiple Eph receptors tested\",\n      \"pmids\": [\"32060095\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Conditional SHB inactivation in endothelial cells (Cdh5-CreERt2) reduces tumor growth, reduces vascular leakage, increases hypoxia, and alters adherens junction and focal adhesion gene expression in tumor endothelial cells; conditional SHB inactivation in pericytes (Pdgfrb-CreERt2) decreases pericyte coverage, increases vascular leakage, causes aberrant PDGFRB signaling, and increases lung metastasis without affecting tumor growth, establishing distinct roles of endothelial vs. pericyte SHB.\",\n      \"method\": \"Conditional cell-type-specific Cre-loxP knockout, tumor implantation, flow cytometry, immunofluorescence for vascular markers, RNAseq, vascular permeability assay\",\n      \"journal\": \"International journal of cancer\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — cell-type-specific conditional knockouts with clear mechanistic dissection between two vascular compartments\",\n      \"pmids\": [\"32441314\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"SHB is a ubiquitously expressed scaffold/adaptor protein that recruits signaling complexes downstream of multiple receptor tyrosine kinases (VEGFR-2, FGFR-1, PDGFR, TrkA, EphB2, IL-2R, TCR) by binding phosphotyrosine motifs via its SH2 and PTB domains and proline-rich sequences via SH3 domain partners; through context-dependent assembly of complexes including FAK, PI3K, IRS-1/2, Rac1, Rap1, c-Abl, PLC-γ1, LAT, SLP-76, Vav, Nck, RasGAP, and Chimaerins, SHB regulates cell survival/apoptosis, migration, cytoskeletal organization, vascular permeability, angiogenesis, hematopoietic stem cell proliferation, T cell activation, and insulin secretion, with SHB phosphorylation at specific tyrosines (including Y1175 of VEGFR-2 as docking site, and Y246/Y297/Y336 of SHB itself for EphB2 signaling) being critical determinants of complex composition and downstream output.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"SHB is a multi-domain scaffold/adaptor protein that couples diverse receptor tyrosine kinases to downstream signaling cascades controlling cell survival, migration, cytoskeletal remodeling, and exocytosis. Its SH2 domain docks onto phosphotyrosine residues of VEGFR-2 (Y1175), FGFR-1 (Y766), PDGFR-α (Y720), IL-2Rβ (Y510), TCR ζ-chain, and Eph receptors, while its PTB domain binds FAK and its proline-rich motifs recruit SH3-containing partners including Src, PI3K p85α, Grb2, and JAK1/3, thereby assembling context-dependent multiprotein complexes that activate PI3K/Akt, Rac1, Rap1, MAPK, and FAK pathways [PMID:7537362, PMID:15026417, PMID:9484780, PMID:12464388, PMID:32060095]. In vivo, Shb knockout mice exhibit defective VEGF-induced vascular permeability, impaired angiogenesis and tumor growth, reduced hematopoietic stem cell proliferation due to constitutively elevated FAK signaling, blunted first-phase insulin secretion from pancreatic β-cells, and skewed T-cell Th1/Th2 balance [PMID:19223532, PMID:23528453, PMID:25274988, PMID:19696098, PMID:21223549]. SHB phosphorylation at specific tyrosines (Y246, Y297, Y336) further dictates effector recruitment — for example recruiting Nck and chimaerin Rac GAPs downstream of EphB2 to drive cell boundary formation — establishing SHB as a phosphotyrosine-dependent signaling hub whose complex composition determines cellular output [PMID:32060095, PMID:32441314].\",\n  \"teleology\": [\n    {\n      \"year\": 1994,\n      \"claim\": \"Identification of SHB as a novel SH2-domain adaptor that selectively binds the autophosphorylated PDGF β-receptor established it as a new class of signaling scaffold linking RTKs to SH3-domain effectors.\",\n      \"evidence\": \"GST-SH2 pulldown, Western blot, cDNA cloning in fibroblasts\",\n      \"pmids\": [\"8302579\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No downstream signaling consequence demonstrated\", \"Endogenous expression pattern not yet defined\"]\n    },\n    {\n      \"year\": 1995,\n      \"claim\": \"Mapping the SH2 binding specificity (pY-T/V/I-X-L) and showing proline-rich motifs recruit Src, PI3K p85α, and Eps8 SH3 domains defined the modular logic by which SHB assembles multiprotein complexes.\",\n      \"evidence\": \"Degenerate phosphopeptide library, PDGFR Y→F mutants, GST-SH3 pulldowns, co-immunoprecipitation\",\n      \"pmids\": [\"7537362\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"In vivo relevance of individual SH3 interactions not tested\", \"PTB domain function not yet characterized\"]\n    },\n    {\n      \"year\": 1996,\n      \"claim\": \"Demonstration that SHB overexpression induces apoptosis rescued by PDGF-BB but not IGF-1 provided the first evidence that SHB transduces receptor-specific survival/death signals.\",\n      \"evidence\": \"Stable NIH3T3 overexpression, TUNEL assay, growth factor rescue\",\n      \"pmids\": [\"8806685\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Overexpression artifact possible\", \"Mechanism of apoptosis induction not defined\"]\n    },\n    {\n      \"year\": 1998,\n      \"claim\": \"Discovery of SHB engagement with TCR ζ-chain via SH2, Grb2 via proline-rich motifs, and a novel PTB domain (binding Asp-Asp-X-pTyr) expanded SHB's receptor repertoire beyond RTKs to immune receptor signaling.\",\n      \"evidence\": \"Co-IP in Jurkat cells, phosphopeptide library for PTB, dominant-negative R522K mutant\",\n      \"pmids\": [\"9484780\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Identity of 36/38 kDa PTB-binding partner uncertain\", \"Physiological T-cell phenotype not yet tested in vivo\"]\n    },\n    {\n      \"year\": 1999,\n      \"claim\": \"Linking SHB to PLC-γ1, LAT phosphorylation, calcium flux, MAPK, and NFAT/IL-2 production downstream of TCR positioned SHB as a proximal organizer of T-cell activation signaling.\",\n      \"evidence\": \"Dominant-negative SHB in Jurkat cells, calcium imaging, NFAT reporter, IL-2 ELISA\",\n      \"pmids\": [\"10488157\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No loss-of-function in primary T cells yet\", \"Mechanism of LAT phosphorylation regulation unclear\"]\n    },\n    {\n      \"year\": 2000,\n      \"claim\": \"Multiple studies converged to show SHB regulates small GTPases Rac1 and Rap1 downstream of PDGFR, FGFR, and TrkA, controlling cytoskeletal organization, neurite outgrowth, and cell morphology — establishing Rac/Rap as core SHB effector axes.\",\n      \"evidence\": \"Rac1/Rap1 activity pulldowns, CrkII co-IP, PDGFR Y→F mutants, dominant-negative Rap1 approaches in NIH3T3, PC12, and IBE cells\",\n      \"pmids\": [\"10837138\", \"10878015\", \"10964504\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct versus indirect regulation of GTPases not resolved\", \"Endogenous SHB loss-of-function not tested\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"SHB was shown to scaffold SLP-76, Vav, Gads, and ZAP70 at TCR lipid rafts, and separately to nucleate IRS-1/IRS-2/FAK/PI3K complexes in β-cells, demonstrating how SHB's multiple domains build tissue-specific signaling platforms.\",\n      \"evidence\": \"Co-IP domain mapping and lipid raft fractionation in Jurkat cells; co-IP and Akt phosphorylation in RINm5F β-cells\",\n      \"pmids\": [\"12084069\", \"12520086\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Stoichiometry and dynamics of multiprotein complexes unknown\", \"Structural basis for simultaneous multi-partner engagement absent\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Mapping SHB SH2 domain binding to FGFR-1 Y766 and showing dominant-negative SHB blocks FRS2 phosphorylation and MAPK-dependent proliferation placed SHB as an intermediary between FGFR-1 and the Ras/MAPK cascade.\",\n      \"evidence\": \"Chimeric receptor with Y766F mutation, GST-SH2 pulldown, proliferation assay\",\n      \"pmids\": [\"12181353\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether SHB directly activates FRS2 or acts through a kinase intermediate not resolved\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Identification of the PTB domain as the FAK-binding module and Src as the kinase phosphorylating SHB established the FAK–SHB–Src signaling node that recurs across many SHB functions.\",\n      \"evidence\": \"PTB domain fusion pulldown, temperature-sensitive v-Src cells, Src inhibitor, FAK phosphorylation blots\",\n      \"pmids\": [\"12464388\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct binding interface between PTB and FAK not structurally defined\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Demonstrating that SHB SH2 domain docks on VEGFR-2 Y1175 and that SHB knockdown abolishes VEGF-induced PI3K, FAK phosphorylation, and endothelial migration established SHB as a critical mediator of VEGF signaling.\",\n      \"evidence\": \"GST-SH2 pulldown with VEGFR-2 peptides, siRNA in endothelial cells, PI3K assay, FAK/migration readouts\",\n      \"pmids\": [\"15026417\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"In vivo vascular consequence not yet shown at this point\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Shb knockout mice revealed that loss of SHB causes dysfunctional endothelial ultrastructure, increased baseline vascular permeability, reduced VEGF-stimulated permeability, and impaired tumor angiogenesis — providing the first in vivo validation of SHB's vascular functions.\",\n      \"evidence\": \"Shb global knockout, electron microscopy, vascular permeability assays, tumor implantation\",\n      \"pmids\": [\"19223532\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Endothelial-specific versus systemic contributions not separated\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Patch-clamp capacitance measurements in Shb-null islets showed dramatically reduced readily releasable insulin granules despite normal Ca2+ handling, pinpointing SHB's role to the exocytotic machinery rather than stimulus-secretion coupling upstream of Ca2+.\",\n      \"evidence\": \"Patch-clamp electrophysiology, pancreatic perfusion, islet vascular imaging in knockout mice\",\n      \"pmids\": [\"19696098\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular target in exocytotic machinery not identified\", \"Relative contribution of vascular versus β-cell-intrinsic defects unclear\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Finding that Shb-null LT-HSCs have constitutively elevated FAK/Rac1/PAK signaling and that FAK inhibition rescues their proliferation defect established SHB as a negative regulator of FAK in hematopoietic stem cells.\",\n      \"evidence\": \"Flow cytometry of bone marrow, competitive transplantation, FAK/Rac1 Western blots, FAK inhibitor rescue in knockout\",\n      \"pmids\": [\"23528453\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism by which SHB restrains FAK activity not defined\", \"Whether this applies to all stem cell contexts unknown\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Live-cell cAMP FRET imaging showed that chronically elevated FAK in Shb-null β-cells delays glucose-induced sub-membrane cAMP rise, causally linking FAK hyperactivation to the insulin secretion defect and resolving the downstream mechanism.\",\n      \"evidence\": \"cAMP FRET biosensor, patch-clamp, FAK inhibitor rescue in Shb-knockout islets\",\n      \"pmids\": [\"25274988\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How FAK suppresses cAMP generation molecularly is unknown\", \"Whether FAK inhibition fully rescues secretion in vivo not tested\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"TIRF microscopy resolved the temporal sequence of VEGFR2–SHB–FAK co-localization at the plasma membrane (<2.5 min) and showed SHB is required for VEGFR2-dependent FAK recruitment to focal adhesions, providing the real-time spatial mechanism.\",\n      \"evidence\": \"TIRF live-cell imaging, Y1175F-VEGFR2 mutant, SHB-knockout primary endothelial cells\",\n      \"pmids\": [\"31847469\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether SHB directly bridges VEGFR2 and FAK or acts through intermediaries not resolved at the molecular level\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Identification of SHB phosphotyrosines Y246, Y297, and Y336 as docking sites for Nck, RasGAP, and chimaerin Rac GAPs downstream of EphB2 revealed how SHB's own phosphorylation pattern encodes effector specificity for Eph-mediated cell segregation.\",\n      \"evidence\": \"Phosphospecific Y→F mutagenesis, mass spectrometry interactome, HEK293 cell segregation assay with multiple Eph receptors\",\n      \"pmids\": [\"32060095\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis for multi-site phosphorylation decoding unknown\", \"In vivo Eph boundary phenotype in Shb knockout not tested\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Cell-type-specific conditional knockouts separated endothelial SHB (controls vascular leakage and tumor angiogenesis) from pericyte SHB (controls pericyte coverage and metastatic dissemination), demonstrating compartmentalized functions within the vascular niche.\",\n      \"evidence\": \"Cdh5-CreERt2 and Pdgfrb-CreERt2 conditional Shb knockouts, tumor implantation, RNAseq, vascular permeability\",\n      \"pmids\": [\"32441314\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Downstream signaling pathways in pericytes not deeply characterized\", \"Therapeutic relevance of targeting SHB in specific vascular compartments not established\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"Key unresolved questions include the structural basis for simultaneous multi-domain engagement of distinct partners, the mechanism by which SHB restrains FAK kinase activity, and whether SHB phosphorylation codes are conserved across receptor contexts in vivo.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No crystal or cryo-EM structure of SHB or its complexes\", \"No systematic in vivo phosphosite mutant analysis across tissues\", \"Mechanism by which SHB suppresses basal FAK activity remains undefined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [0, 1, 4, 13, 14, 17, 18, 35]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [13, 34]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [0, 4]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 1, 6, 12, 18, 28, 35]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [4, 6, 13, 16, 27]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [19, 20, 26]},\n      {\"term_id\": \"R-HSA-5357801\", \"supporting_discovery_ids\": [2, 8, 21, 23]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"FAK\", \"VEGFR2\", \"FGFR1\", \"PI3K\", \"SLP76\", \"Vav1\", \"Nck\", \"c-Abl\"],\n    \"other_free_text\": []\n  }\n}\n```"}