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Originally published In Press as doi:10.1074/jbc.M801319200 on May 15, 2008
J. Biol. Chem., Vol. 283, Issue 33, 22709-22722, August 15, 2008
Potential Molecular Mechanism for c-Src Kinase-mediated Regulation of Intestinal Cell Migration*
Sijo Mathew1,
Sudeep P. George1,
Yaohong Wang,
Mohammad Rizwan Siddiqui,
Kamalakkannan Srinivasan,
Langzhu Tan, and
Seema Khurana2
From the
Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163
The ubiquitously expressed Src tyrosine kinases (c-Src, c-Yes, and c-Fyn) regulate intestinal cell growth and differentiation. Src activity is also elevated in the majority of malignant and premalignant tumors of the colon. The development of fibroblasts with the three ubiquitously expressed kinases deleted (SYF cells) has identified the role of Src proteins in the regulation of actin dynamics associated with increased cell migration and invasion. Despite this, unexpectedly nothing is known about the role of the individual Src kinases on intestinal cell cytoskeleton and/or cell migration. We have previously reported that villin, an epithelial cell-specific actin-modifying protein that regulates actin reorganization, cell morphology, cell migration, cell invasion, and apoptosis, is tyrosine-phosphorylated. In this report using the SYF cells reconstituted individually with c-Src, c-Yes, c-Fyn, and wild type or phosphorylation site mutants of villin, we demonstrate for the first time the absolute requirement for c-Src in villin-induced regulation of cell migration. The other major finding of our study is that contrary to previous reports, the nonreceptor tyrosine kinase, Jak3 (Janus kinase 3), does not regulate phosphorylation of villin or villin-induced cell migration and is, in fact, not expressed in intestinal epithelial cells. Further, we identify SHP-2 and PTP-PEST (protein-tyrosine phosphatase proline-, glutamate-, serine-, and threonine-rich sequence) as negative regulators of c-Src kinase and demonstrate a new function for these phosphatases in intestinal cell migration. Together, these data suggest that in colorectal carcinogenesis, elevation of c-Src or down-regulation of SHP-2 and/or PTP-PEST may promote cancer metastases and invasion by regulating villin-induced cell migration and cell invasion.
Received for publication, February 19, 2008
, and in revised form, May 14, 2008.
* This work was supported, in whole or in part, by National Institutes of Health NIDDK Grants DK-65006 and DK-54755 (to S. K.). The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
The on-line version of this article (available at http://www.jbc.org) contains supplemental Fig. 1.
1 Both authors contributed equally to this work.
2 To whom correspondence should be addressed: Dept. of Physiology, The University of Tennessee Health Science Center, Nash 402, 894 Union Ave., Memphis, TN 38163. Tel.: 901-448-3410; Fax: 901-448-3505; E-mail: skhurana{at}utmem.edu.

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Copyright © 2008 by the American Society for Biochemistry and Molecular Biology.
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