| 2005 |
SH2B1 (SH2-B) is an endogenous enhancer of leptin sensitivity that binds JAK2 and promotes leptin-stimulated activation of hypothalamic JAK2, phosphorylation of STAT3 and IRS2; SH2B1 null mice show severely impaired leptin signaling and develop obesity, hyperglycemia, and metabolic syndrome. |
Genetic knockout mouse model; leptin signaling assays (JAK2 activation, STAT3/IRS2 phosphorylation); cultured cell overexpression with PTP1B inhibition assay |
Cell metabolism |
High |
16098827
|
| 2004 |
SH2B1 promotes activation of the PI3-kinase pathway in response to leptin by directly binding IRS1 and IRS2 (via its PH and SH2 domains) and mediating formation of a JAK2/SH2B1/IRS1 or IRS2 ternary complex, thereby enhancing leptin-stimulated tyrosine phosphorylation of IRS1/IRS2 and subsequent PI3K/Akt activation. |
In vitro binding assays (GST pulldown), co-immunoprecipitation in HEK293 cells stably expressing LRb, mutagenesis of SH2B1 binding domains, MEF KO reconstitution |
The Journal of biological chemistry |
High |
15316008
|
| 2004 |
SH2B1 (SH2-B) directly enhances insulin receptor autophosphorylation and tyrosine phosphorylation of IRS1/IRS2 in an SH2 domain-dependent manner; systemic deletion of SH2-B impairs insulin receptor signaling in liver, muscle, and fat and causes age-dependent hyperinsulinemia, hyperglycemia, and glucose intolerance. |
Genetic KO mouse; in vitro kinase assays; cultured cell overexpression and KO analysis of IR, IRS1/IRS2 phosphorylation, Akt and ERK1/2 activation |
Molecular and cellular biology |
High |
15314154
|
| 2004 |
Tyrosine 813 is a site of JAK2 autophosphorylation (identified by 2D phosphopeptide mapping and phospho-specific antibody) that is required for SH2B1β to bind JAK2 and to enhance JAK2 activity and STAT5B phosphorylation; the homologous Tyr785 in JAK3 is similarly autophosphorylated and required for SH2B1β binding. |
2D phosphopeptide mapping, phosphospecific antibody, mutagenesis (Y813F), co-immunoprecipitation, kinase activity assays |
Molecular and cellular biology |
High |
15121872
|
| 2007 |
SH2B1 regulates leptin/JAK2 signaling by dual mechanisms: (1) constitutive binding via non-SH2 domain to non-phosphorylated JAK2 inhibits basal JAK2; (2) leptin-stimulated JAK2 phosphorylation at Tyr813 recruits the SH2 domain of SH2B1 to activate JAK2; additionally, SH2B1 interacts with IRS1 to facilitate IRS1 phosphorylation independent of JAK2 Tyr813. |
Co-immunoprecipitation, JAK2 Y813F mutagenesis, leptin stimulation assays, IRS1 phosphorylation assays in cultured cells |
Molecular endocrinology |
High |
17565041
|
| 2007 |
Neuronal SH2B1β specifically expressed in neural tissue is sufficient to correct metabolic disorders (obesity, leptin resistance, insulin resistance, glucose intolerance) in SH2B1 knockout mice and improves hypothalamic JAK2-mediated leptin signaling, demonstrating that neuronal SH2B1 is the primary site of metabolic action. |
Neuron-specific SH2B1 transgenic rescue crossed onto KO background (TgKO mice); hypothalamic leptin signaling assays; metabolic phenotyping |
The Journal of clinical investigation |
High |
17235396
|
| 2009 |
Peripheral SH2B1 directly stimulates insulin receptor catalytic activity (demonstrated by in vitro kinase assay with purified SH2B1) and inhibits tyrosine dephosphorylation of IRS-1/IRS-2 by binding to them; the SH2 domain alone is both required and sufficient for insulin receptor activation. |
In vitro insulin receptor kinase assay with purified SH2B1; in vitro IRS dephosphorylation assay; TgKO mice expressing SH2B1 only in brain; co-immunoprecipitation |
Diabetes |
High |
19542202
|
| 2001 |
SH2B1 (SH2-B) and APS exist as homopentamers and/or heteropentamers mediated by their N-terminal dimerization domain; SH2-B multimerization is required for enhancing TrkA autophosphorylation magnitude and duration in response to NGF and for TrkA/SH2-B-mediated morphological differentiation of PC12 cells. |
Biochemical structure-function analysis; co-immunoprecipitation; dominant-negative overexpression; PC12 cell NGF differentiation assays |
Molecular and cellular biology |
Medium |
11238898
|
| 1999 |
SH2B1β (SH2-Bbeta) is required for NGF-induced neuronal differentiation: it binds to activated TrkA via its SH2 domain, is tyrosyl-phosphorylated in response to NGF, and overexpression of a dominant-negative SH2 domain mutant (R555E) blocks NGF-induced neurite outgrowth in PC12 cells without altering TrkA, Shc, PLCγ phosphorylation or ERK1/2 activation, indicating a novel downstream pathway. |
GST-fusion pulldown, co-immunoprecipitation, overexpression of wild-type and SH2 domain mutant in PC12 cells, neurite outgrowth assay |
The Journal of biological chemistry |
High |
10187854
|
| 1999 |
SH2B1 (SH2-Bgamma isoform) interacts specifically with the insulin receptor kinase domain, requiring phosphorylation of Y1146 in the activation loop triple-tyrosine motif, making it one of only two signaling molecules shown to interact directly with this residue. |
In vitro binding assays with insulin receptor kinase domain, mutagenesis of IR Y1146 |
Mammalian genome |
Medium |
10594240
|
| 2000 |
SH2B1β (SH2-Bbeta) is required for growth hormone-induced actin reorganization (membrane ruffling and pinocytosis); it co-localizes with filamentous actin in GH-induced membrane ruffles; both SH2 domain-defective and truncation mutants lacking the N-terminus inhibit GH-induced ruffling, acting via a mechanism distinct from JAK2 kinase stimulation. |
Cell fractionation, confocal microscopy, overexpression of wild-type and mutant SH2B1 in 3T3-F442A cells, membrane ruffling and pinocytosis assays |
The Journal of biological chemistry |
Medium |
10777618
|
| 2001 |
SH2B1β specifically activates JAK2 (but not JAK1 or JAK3) when overexpressed, while APS negatively regulates JAK2 and JAK1 but not JAK3; both bind and are phosphorylated by JAK kinases, demonstrating isoform- and kinase-specificity of SH2B family regulation. |
Overexpression in cells, co-immunoprecipitation, kinase activity/phosphorylation assays for JAK1, JAK2, JAK3, STAT5B |
The Journal of biological chemistry |
Medium |
11751854
|
| 2002 |
SH2B1β binds to FGFR3 via the SH2 domain at FGFR3 phosphotyrosines Tyr-724 and Tyr-760; SH2B1β is tyrosyl-phosphorylated by activated FGFR3 mutants and enhances FGFR3-stimulated STAT5 phosphorylation and nuclear translocation. |
Yeast two-hybrid screen, co-immunoprecipitation, FGFR3 mutagenesis (Y724, Y760), STAT5 nuclear translocation assay |
The Journal of biological chemistry |
Medium |
11827956
|
| 2004 |
SH2B1β undergoes constitutive nucleocytoplasmic shuttling; a nuclear export sequence (amino acids 224–233) containing two critical lysines is required for cytoplasmic/membrane localization and for SH2B1β to enhance NGF-induced neurite outgrowth; nuclear-export-defective mutants cannot support differentiation despite normal ERK activation. |
Leptomycin B treatment, NES deletion/mutation, confocal microscopy in PC12 and COS-7 cells, stable overexpression neurite outgrowth assay |
Molecular and cellular biology |
Medium |
15082760
|
| 1999 |
NGF stimulates phosphorylation of SH2B1 (SH2-B) on multiple serines/threonines via kinases downstream of MEK (ERKs 1 and 2 phosphorylate SH2Bbeta on Ser-96 in vitro); however, the S96A mutant still supports NGF-induced neurite outgrowth, suggesting additional MEK-downstream sites are involved. |
In vitro ERK kinase assay, MEK inhibitor PD98059, protein phosphatase 2A treatment, mutagenesis (S96A), NGF-induced differentiation assay |
The Journal of biological chemistry |
Medium |
10473609
|
| 2005 |
SH2B1 homodimerizes (and forms heterodimers with APS) via a unique N-terminal domain; dimerization brings two SH2 domains to bind two JAK2 pTyr813 sites, creating heterotetrameric JAK2-(SH2B1)2-JAK2 complexes that transactivate JAK2 at low adapter concentrations, but inhibit kinase activity at high concentrations. |
Yeast two-hybrid, cellular transfection co-immunoprecipitation, kinase activity assays at varying SH2B1/APS concentrations |
Molecular and cellular biology |
Medium |
15767667
|
| 2006 |
SH2B1 (and APS) bind JAK2 at multiple sites; binding at pTyr813 is essential for SH2B1-mediated JAK2 activation; a phosphoTyr813-independent binding site mediates inhibition; the region 809–811 in JAK2, likely within JH1/JH2 domains, is a critical component of the regulatory region that SH2B1 binding stabilizes into an active conformation. |
JAK2 truncation and point mutagenesis, in vitro kinase assays, binding assays for multiple JAK2 sites |
Molecular and cellular biology |
Medium |
16914724
|
| 2006 |
Crystal structure (2.35 Å) of the SH2B1 SH2 domain in complex with the JAK2 pTyr813 phosphopeptide reveals canonical SH2-phosphopeptide binding with specific recognition of glutamate at +1 and hydrophobic at +3 positions; the SH2B1 SH2 domain prefers JAK2 over insulin receptor due to its monomeric state (versus dimeric APS SH2). |
X-ray crystallography (2.35 Å), biochemical binding assays comparing SH2B1 vs APS SH2 domains |
Journal of molecular biology |
High |
16824542
|
| 2003 |
SH2B1β is a positive regulator of NGF-mediated Akt/PKB activation in PC12 cells; it enhances and prolongs NGF-induced phosphorylation of Akt on Ser473, leading to increased phosphorylation of GSK-3 and FOXO forkhead transcription factors and their cytoplasmic retention; a dominant-negative SH2 domain mutant blocks these effects. |
Stable overexpression of SH2Bbeta and R555E mutant in PC12 cells, Akt kinase assays, phospho-Akt/GSK-3/FOXO western blotting, immunolocalization of FKHR |
The Journal of biological chemistry |
Medium |
14565960
|
| 2007 |
SH2B2β, a novel isoform of SH2B2 lacking an SH2 domain, acts as an endogenous inhibitor of SH2B1: it binds SH2B1 via the dimerization/PH domain and markedly attenuates SH2B1-promoted JAK2 activation, IRS-1 phosphorylation by JAK2, and insulin-stimulated IRS-1 phosphorylation. |
GST-fusion pulldown in vitro, co-immunoprecipitation in intact cells, JAK2 kinase assays, insulin signaling assays |
Endocrinology |
Medium |
17204555
|
| 2007 |
SH2B1 (SH2-B) promotes adipocyte differentiation by enhancing insulin/IGF-I receptor signaling through Akt, leading to phosphorylation and nuclear exclusion of Foxo1, thereby increasing PPARγ mRNA levels; PPARγ up-regulation by SH2B1 is blocked by PI3K inhibitors but not MEK inhibitors. |
Retroviral overexpression and KO MEF differentiation assays, PPARγ mRNA quantification, Akt/Foxo1 phosphorylation assays, PI3K and MEK inhibitor treatments |
Molecular endocrinology |
Medium |
17312274
|
| 2010 |
Neuronal SH2B1 regulates energy balance by controlling a leptin receptor neuron/sympathetic nervous system (SNS)/brown adipose tissue/thermogenesis axis; LepR neuron-specific deletion of Sh2b1 abrogates leptin-stimulated sympathetic nerve activation and impairs BAT thermogenic programs, causing cold intolerance and progressive degeneration of adipose SNS. |
LepR neuron-specific conditional KO, adult-onset hypothalamic-specific AAV-ablation, hypothalamic overexpression; sympathetic nerve recording; BAT thermogenesis measurement; metabolic phenotyping |
Nature communications |
High |
32251290
|
| 2010 |
The SH2 domain of neuronal SH2B1 is required for maintaining normal body weight and glucose metabolism in vivo; SH2 domain-defective mutant (R555E) expressed neuron-specifically in WT mice promotes obesity and insulin resistance in a dominant-negative manner, while the SH2 domain alone (DeltaN503) is insufficient to rescue the KO phenotype, demonstrating N-terminal regions are also required. |
Three lines of neuron-specific transgenic mice (WT, R555E, DeltaN503) crossed with SH2B1 KO; metabolic phenotyping; glucose/insulin tolerance tests |
Endocrinology |
Medium |
20484460
|
| 2012 |
SH2B1 associates with the erythropoietin receptor (EPO-R) via its SH2 domain at phosphotyrosines 343 and 401 (pYXXL sequence); SH2B1β preferentially associates with EPO-R over JAK2 in hematopoietic cells; constitutive SH2B1 association with EPO-R is necessary for optimal SH2-dependent recruitment; absence of SH2B1 leads to enhanced EPO-R downstream signaling, indicating SH2B1 is a negative regulator of EPO signaling. |
COLT screening, co-immunoprecipitation, in vitro mixing assays, SH2 domain mutagenesis, EPO stimulation signaling assays in cells lacking SH2B1 |
The Journal of biological chemistry |
Medium |
22669948
|
| 2013 |
SH2B1 in pancreatic β-cells promotes β-cell survival and proliferation by enhancing insulin- and IGF-1-stimulated PI3K/Akt activation; pancreas-specific KO mice show increased β-cell apoptosis, decreased proliferation, reduced β-cell mass, and exacerbated glucose intolerance on high-fat diet. |
Pancreas-specific conditional KO mice; high-fat diet metabolic phenotyping; STZ challenge; β-cell mass histomorphometry; PI3K/Akt signaling assays in INS-1 cells and islets |
Diabetes |
Medium |
24150605
|
| 2013 |
SH2B1 promotes insulin expression in β-cells by enhancing JAK2 activation of the insulin promoter and increasing Pdx1 expression and Pdx1 recruitment to the insulin promoter; SH2B1 knockdown reduces, and overexpression increases, insulin expression and glucose-stimulated insulin secretion. |
siRNA knockdown and overexpression in INS-1 832/13 cells; insulin promoter-luciferase assay; chromatin immunoprecipitation (ChIP) for Pdx1; SH2B1-deficient islet analysis |
Molecular endocrinology |
Medium |
24645678
|
| 2015 |
SH2B1 mediates pathological cardiac hypertrophy by activating the JAK2/STAT3 signaling cascade; cardiac-specific SH2B1 overexpression exacerbates pressure overload-induced hypertrophy, whereas SH2B1 deletion is protective; pharmacological JAK2 inactivation rescues hypertrophic abnormalities in SH2B1-overexpressing transgenic mice. |
Cardiac-specific SH2B1 transgenic mice and global KO rat model; aortic banding model; echocardiography; JAK2/STAT3 pathway assays; JAK2 inhibitor rescue experiments |
Cardiovascular research |
Medium |
26077624
|
| 2015 |
SH2B1β interacts with IRSp53 via its N-terminal proline-rich domains; SH2B1-IRSp53 complexes co-localize at the plasma membrane and together promote filopodium formation, neurite initiation, and dendritic branching in hippocampal and cortical neurons. |
Co-immunoprecipitation in vivo and in vitro, confocal co-localization, Triton X-100 fractionation, overexpression of SH2B1β and IRSp53 in neurons, neurite/filopodia counting |
The Journal of biological chemistry |
Medium |
25586189
|
| 2013 |
SH2B1 promotes BDNF-induced neurite outgrowth by enhancing MEK-ERK1/2 and PI3K-AKT signaling pathways downstream of TrkB; SH2B1β also enhances BDNF-stimulated STAT3 phosphorylation on Ser727; the SH2 domain and tyrosine phosphorylation of SH2B1β are required for these effects. |
Overexpression of SH2B1β and mutants in PC12-TrkB and hippocampal cells; pathway inhibitors (MEK, PI3K); neurite outgrowth assays; western blotting of p-ERK, p-AKT, p-STAT3 |
PloS one |
Medium |
24260264
|
| 2018 |
SH2B1β is phosphorylated by TrkA at Tyr753 in the unique α-tail (and at Tyr439 and Tyr55 shared by α and β isoforms); phosphorylation of Tyr753 in SH2B1α inhibits nucleocytoplasmic cycling and prevents SH2B1α from enhancing NGF-mediated neurite outgrowth, TrkA autophosphorylation, Akt/PLCγ phosphorylation, and gene expression; Y753F mutation restores these functions. |
Mutagenesis (Y753F and others), co-expression with TrkA, neurite outgrowth assays, western blotting for p-Akt and p-PLCγ, nuclear cycling assays |
Molecular and cellular biology |
Medium |
29229648
|
| 2016 |
SH2B1 interacts with histone H1 and is required for removal of histone H1 from active transcription sites; SH2B1 promotes histone H3K4me3 induction and H3K9me3 reduction at IGF2 and MYOG promoters/enhancers, is required for MyoD occupancy at these loci, and promotes myogenesis; knockdown delays chromatin condensation and decreases myotube formation. |
ChIP for histone marks and MyoD occupancy, co-immunoprecipitation with histone H1, SH2B1 knockdown, myotube formation assays |
Biochimica et biophysica acta. Gene regulatory mechanisms |
Medium |
28039048
|
| 2022 |
SH2B1 promotes myelination in peripheral nervous system Schwann cells by maintaining phosphorylation of cytohesin-2 at Tyr381, which is required for Arf6 activity and normal myelin thickness; Schwann cell-specific loss of SH2B1 reduces cytohesin-2 phosphorylation and myelin thickness; SH2B1 and the phosphatase PTP4A1 act antagonistically to control this phosphorylation. |
Schwann cell-specific knockdown in mice (in vivo), HEK293T co-expression experiments, Y381F cytohesin-2 knockin mice, Arf6 activity assays, myelin thickness measurements |
Science signaling |
Medium |
35077201
|
| 2022 |
SH2B1 neuronal protection against MPTP-induced dopaminergic neurodegeneration is mediated by binding to HSC70, which promotes HSC70-dependent recognition and lysosomal translocation/degradation of PLIN4, thereby suppressing lipid peroxidation stress; Sh2b1 deficiency exacerbates PD-like pathology and AAV-HSC70 rescue is effective only in WT but not Sh2b1-deficient mice. |
MPTP mouse PD model, Sh2b1 KO and neuron-specific overexpression, co-IP of SH2B1-HSC70, PLIN4 degradation assays, AAV-HSC70 rescue, lipid peroxidation measurement |
Redox biology |
Medium |
35390677
|
| 2022 |
The brain-specific SH2B1δ isoform localizes primarily to nucleoli (driven by two unique highly basic regions) and to the plasma membrane; its nucleolar localization is required for SH2B1δ to maximally enhance neurite complexity and BDNF-induced expression of Egr1, Arc, and FosL1 in hippocampal neurons. |
Isoform-specific overexpression in Sh2b1 KO hippocampal neurons, confocal microscopy, mutagenesis of nucleolar targeting regions, neurite morphology analysis, BDNF-induced gene expression assays |
Journal of cell science |
Medium |
35019135
|
| 2016 |
4E-BP2 deletion induces translation of SH2B1, which then forms a complex with IRS2 and JAK2 that prevents IRS2 ubiquitination; this SH2B1-dependent stabilization of IRS2 increases Akt signaling, reduces p27, and promotes β-cell proliferation and survival, linking mTORC1 signaling to IRS2 stability through SH2B1. |
4E-BP2 KO mice, co-immunoprecipitation (SH2B1/IRS2/JAK2 complex), IRS2 ubiquitination assay, Akt/p27 signaling assays, cytokine treatment survival assays |
Diabetes |
Medium |
27217487
|
| 2019 |
The PH domain of SH2B1 is critical for energy balance and glucose homeostasis; mice homozygous for a human obesity-associated P322S PH domain variant show substantial prenatal lethality; mice with a two-amino acid deletion in the PH domain (ΔPR) develop obesity and insulin resistance beyond that attributable to adiposity alone. |
PH domain variant knockin mouse models (P322S and ΔPR); metabolic phenotyping; glucose and insulin tolerance testing |
Diabetes |
Medium |
31439647
|
| 2017 |
The SH2 domain of SH2B1 binds diverse phosphotyrosine-containing peptides (JAK2 pY813, insulin receptor activation loop, IRS-1/2) with distinct thermodynamic signatures; residues K575 and R578 play distinct roles in different binding modes; crystal structure reveals conformationally plastic loops enabling recognition of chemically disparate +3 position residues. |
Binding assays (ITC/fluorescence), X-ray crystallography of SH2B1 SH2 domain, alanine scanning mutagenesis of binding residues |
Proteins |
Medium |
29127727
|
| 2023 |
Hippocampal SH2B1 in inhibitory (but not excitatory) neurons controls fluid intelligence-related cognitive functions (working memory, short-term recognition memory, behavioral flexibility) by restraining ERK signaling; selective ablation of Sh2b1 in hippocampal inhibitory neurons causes aberrantly enhanced ERK signaling, and pharmacological ERK inhibition reverses associated behavioral impairments. |
Cell-type-specific conditional KO in mouse hippocampus (inhibitory vs excitatory neurons), behavioral cognitive testing, single-cell transcriptomic profiling, pharmacological ERK inhibitor rescue |
Research (Washington, D.C.) |
Medium |
38434247
|
| 2008 |
PSM/SH2B1 splice variants (with activity order γ > δ > α > β) enhance Src kinase catalytic activity by increasing V(max) and decreasing K(m) for ATP; SH2B1 variants and Src are found in the same immune complex; SH2B1 also enhances Src-mediated STAT3 activation; dominant-negative PH or SH2 domain peptides inhibit Src activity. |
Co-immunoprecipitation, in vitro Src kinase assays (V(max)/K(m) measurement), Src inhibitor herbimycin A, dominant-negative peptide mimetics, STAT3 reporter assays |
Journal of cellular biochemistry |
Medium |
18247337
|
| 2018 |
Neural deletion of Sh2b1 decreases brain weight and increases reactive aggression; brain-specific KO mice show increased c-fos immunoreactivity in amygdala and periaqueductal gray (core aggression circuits); brain-specific restoration of Sh2b1 normalizes brain size and reverses pathological aggression; at the molecular level, Sh2b1 enhances neurotrophin-stimulated neuronal differentiation and protects against oxidative stress-induced neuronal death. |
Global and brain-specific conditional KO; resident-intruder aggression paradigm; c-fos immunoreactivity mapping; brain-specific AAV restoration; neurotrophin signaling and oxidative stress protection assays |
FASEB journal |
Medium |
29180441
|
| 2020 |
SH2B1 protects cardiomyocytes from ischemia/reperfusion injury via activation of the PI3K/AKT pathway; adenovirus-mediated SH2B1 overexpression reduces I/R-induced apoptosis, ROS, and inflammation; pharmacological PI3K/AKT inhibition (LY294002) abolishes SH2B1's protective effects. |
In vivo I/R model (LAD ligation) and in vitro H/R model in cardiomyocytes; adenoviral SH2B1 overexpression; PI3K inhibitor LY294002; apoptosis, ROS, and inflammation assays |
International immunopharmacology |
Low |
32222636
|