title: hSef inhibits PC-12 cell differentiation by interfering with Ras-mitogen-activated protein kinase MAPK signaling.
abstract: Growth factor signaling by receptor tyrosine kinases regulates several cell fates, such as proliferation and differentiation. Sef was genetically identified as a negative regulator of fibroblast growth factor (FGF) signaling. Using bioinformatic methods and rapid amplification of cDNA ends-PCR, we isolated both the mouse and the human Sef genes, which encoded the Sef protein and Sef-S isoform that was generated through alternative splicing. We provide evidence that the Sef gene products were located mainly on the cell membrane. Co-immunoprecipitation and immunostaining experiments indicate that hSef interacts with FGFR1 and FGFR2 but not FGFR3. Our results demonstrated that stably expressed hSef strongly inhibits FGF2- or nerve growth factor-induced PC-12 cell differentiation. The intracellular domain of hSef is necessary for the inhibitory effect on FGF2-induced PC-12 cell differentiation. Furthermore, our data suggested Sef exerted the negative effect on FGF2-induced PC-12 cell differentiation through the prevention of Ras-mitogen-activated protein kinase signaling, possibly functioning upstream of the Ras molecule. These findings suggest that Sef may play an important role in the regulation of PC-12 cell differentiation.
authors.affiliation: Tsinghua Institute of Genome Research, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084,China.
authors.forename: Shiqin
authors.initials: S
authors.lastname: Xiong
authors.forename: Qiuhui
authors.initials: Q
authors.lastname: Zhao
authors.forename: Zhili
authors.initials: Z
authors.lastname: Rong
authors.forename: Guanrong
authors.initials: G
authors.lastname: Huang
authors.forename: Yiling
authors.initials: Y
authors.lastname: Huang
authors.forename: Peila
authors.initials: P
authors.lastname: Chen
authors.forename: Shuping
authors.initials: S
authors.lastname: Zhang
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.forename: Zhijie
authors.initials: Z
authors.lastname: Chang
mesh_terms: D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D019556:COS Cells; D002454:Cell Differentiation; D002455:Cell Division; D002460:Cell Line; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism; D005346:Fibroblast Growth Factors / Q000378:metabolism; D006801:Humans; D008156:Luciferases / Q000378:metabolism; D020935:MAP Kinase Signaling System; D051379:Mice; D008856:Microscopy, Fluorescence; D008957:Models, Genetic; D008969:Molecular Sequence Data; D016716:PC12 Cells; D010957:Plasmids / Q000378:metabolism; D011233:Precipitin Tests; D020033:Protein Isoforms; D051381:Rats; D018123:Receptors, Interleukin / Q000378:metabolism / Q000502:physiology*; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D013997:Time Factors; D014162:Transfection; D018631:ras Proteins / Q000378:metabolism*
chemical_list: D018076:DNA, Complementary; C477526:IL17RD protein, human; D020033:Protein Isoforms; D018123:Receptors, Interleukin; D016222:Fibroblast Growth Factor 2; D005346:Fibroblast Growth Factors; D008156:Luciferases; D018631:ras Proteins