title: Signaling adaptor protein v-Crk activates Rho and regulates cell motility in 3Y1 rat fibroblast cell line.
abstract: The adaptor protein Crk has been reported to associate with focal adhesions and is thought to be involved in integrin-mediated signaling pathway. However, the precise mechanism of Crk-dependent regulation of cytoskeleton still remains under investigation. In this study, we have established a v-Crk-inducible cell line in rat fibroblasts 3Y1 cells and found that v-Crk activated Rho and induced actin stress fiber formation. In addition to the induction of tyrosine-phosphorylation of p130(Cas) and paxillin, we demonstrated that v-Crk induced threonine-phosphorylated bands sized at 72/78 kDa found specifically in 3Y1 cells. Both of the inhibitors of Rho and Rho-associated kinase, C3 and Y27632, respectively, inhibited these v-Crk-induced biochemical effects. Although v-Crk-induced cells exhibited a decrease of cell motility, integrin stimulation recovered the suppression of motility. Furthermore, v-Crk enhanced motility in chemotactic assay toward fibronectin with additional activation of Rho and the increase of levels of CD44 cleavage. These results suggest that v-Crk activated Rho and induced actin stress fiber formation and CD44 cleavage leading to the regulation of cell motility.
authors.affiliation: Laboratory of Molecular and Cellular Pathology, Hokkaido University School of Medicine, Sapporo 060-8638, Japan.
authors.forename: Masumi
authors.initials: M
authors.lastname: Tsuda
authors.forename: Shinya
authors.initials: S
authors.lastname: Tanaka
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Sawa
authors.forename: Hidesaburo
authors.initials: H
authors.lastname: Hanafusa
authors.forename: Kazuo
authors.initials: K
authors.lastname: Nagashima
mesh_terms: D000209:Acute-Phase Proteins / Q000378:metabolism*; D000818:Animals; D002460:Cell Line; D002465:Cell Movement; D002478:Cells, Cultured; D005347:Fibroblasts / Q000378:metabolism*; D050736:Oncogene Protein v-crk; D010766:Phosphorylation; D010769:Phosphothreonine / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D015682:Retroviridae Proteins, Oncogenic / Q000235:genetics / Q000494:pharmacology*; D015398:Signal Transduction; D013912:Threonine / Q000378:metabolism
chemical_list: D000209:Acute-Phase Proteins; D050736:Oncogene Protein v-crk; D015682:Retroviridae Proteins, Oncogenic; C010781:acute-phase protein rho; D010769:Phosphothreonine; D013912:Threonine