title: SH2B1beta enhances fibroblast growth factor 1 (FGF1)-induced neurite outgrowth through MEK-ERK1/2-STAT3-Egr1 pathway.
abstract: Genetic studies have established the crucial roles of FGF signaling, FGF-induced gene expression and morphogenesis during embryogenesis. In this study, we showed that overexpressing a signaling adaptor protein, SH2B1beta, enhanced FGF1-induced neurite outgrowth in PC12 cells. SH2B1beta has previously been shown to promote nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF)-induced neurite outgrowth, in part, through prolonging NGF and GDNF-induced signaling. To delineate how SH2B1beta promotes FGF1-induced neurite outgrowth, we examined its role in FGF1-dependent signaling. Our data suggest that SH2B1beta enhances and prolongs FGF1-induced MEK-ERK1/2 and PI3K-AKT pathways. We also provided the first evidence that FGF1 induces the phosphorylation of signal transducer and activator of transcription 3 (STAT3) at serine 727 [pSTAT3(S727)] in PC12 cells. SH2B1beta enhances this phosphorylation and the expression of the immediate early gene, Egr1. Through inhibitor assays, we have further shown that MEK-ERK1/2 is required for FGF1-induced neurite outgrowth, pSTAT3(S727) and Egr1 expression. Moreover, inhibiting Rho kinase, ROCK, enhances FGF1-induced neurite outgrowth through pSTAT3(S727)-independent manner. Taken together, our results demonstrate, for the first time, that SH2B1beta enhances FGF1-induced neurite outgrowth in PC12 cells mainly through MEK-ERK1/2-STAT3-Egr1 pathway.
authors.affiliation: Institute of Molecular Medicine, Department of Life Science and Brain Research Center, National Tsing Hua University, 101 Section 2 Kuang-Fu Road, Hsinchu, Taiwan.
authors.forename: Wei-Fan
authors.initials: WF
authors.lastname: Lin
authors.forename: Chien-Jen
authors.initials: CJ
authors.lastname: Chen
authors.forename: Yu-Jung
authors.initials: YJ
authors.lastname: Chang
authors.forename: Su-Liang
authors.initials: SL
authors.lastname: Chen
authors.forename: Ing-Ming
authors.initials: IM
authors.lastname: Chiu
authors.forename: Linyi
authors.initials: L
authors.lastname: Chen
mesh_terms: D000818:Animals; D002070:Butadienes / Q000494:pharmacology; D002352:Carrier Proteins / Q000378:metabolism*; D002867:Chromones / Q000494:pharmacology; D051766:Early Growth Response Protein 1 / Q000378:metabolism*; D016220:Fibroblast Growth Factor 1 / Q000494:pharmacology*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D048369:MAP Kinase Kinase 1 / Q000378:metabolism; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009025:Morpholines / Q000494:pharmacology; D009414:Nerve Growth Factors / Q000494:pharmacology; D016501:Neurites / Q000187:drug effects* / Q000201:enzymology*; D009570:Nitriles / Q000494:pharmacology; D016716:PC12 Cells; D010766:Phosphorylation / Q000187:drug effects; D017434:Protein Structure, Tertiary; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D050796:STAT3 Transcription Factor / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors
chemical_list: D002070:Butadienes; D002352:Carrier Proteins; D002867:Chromones; D051766:Early Growth Response Protein 1; C486110:Egr1 protein, rat; D047908:Intracellular Signaling Peptides and Proteins; D009025:Morpholines; D009414:Nerve Growth Factors; D009570:Nitriles; D011993:Recombinant Fusion Proteins; C492010:SH2B1 protein, rat; D050796:STAT3 Transcription Factor; C494088:Stat3 protein, rat; C113580:U 0126; D016220:Fibroblast Growth Factor 1; D049452:Green Fluorescent Proteins; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; D051057:Proto-Oncogene Proteins c-akt; D054460:rho-Associated Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048369:MAP Kinase Kinase 1