Requirement of Nck adaptors for actin dynamics and cell migration stimulated by platelet-derived growth factor B

doi:10.1073/pnas.0603786103

Requirement of Nck adaptors for actin dynamics and cell migration stimulated by platelet-derived growth factor B

*Raymond and Beverly Sackler Laboratory of Genetics and Molecular Medicine, Department of Genetics and Developmental Biology and Center for Cell Analysis and Modeling, University of Connecticut Health Center, Farmington, CT 06030;
^†Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, ON, Canada M5G 1X5; and
^‡Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232

Contributed by T. Pawson, May 8, 2006

Abstract

The Nck family of Src homology (SH) 2/SH3 domain adaptors functions to link tyrosine phosphorylation induced by extracellular signals with downstream regulators of actin dynamics. We investigated the role of mammalian Nck adaptors in signaling from the activated platelet-derived growth factor (PDGF) receptor (PDGFβR) to the actin cytoskeleton. We report here that Nck adaptors are required for cytoskeletal reorganization and chemotaxis stimulated by PDGF-B. Analysis of tyrosine-phosphorylated proteins demonstrated that Crk-associated substrate (p130^Cas), not the activated PDGFβR itself, is the major Nck SH2 domain-binding protein in PDGF-B-stimulated cells. Both Nck- and p130^Cas-deficient cells fail to display cytoskeletal rearrangements, including the formation of membrane ruffles and the disassembly of actin bundles, typically shown by their WT counterparts in response to PDGF-B. Furthermore, Nck and p130^Cas colocalize in phosphotyrosine-enriched membrane ruffles induced by PDGF-B in NIH 3T3 cells. These results suggest that Nck adaptors play an essential role in linking the activated PDGFβR with actin dynamics through a pathway that involves p130^Cas.

Footnotes

^§To whom correspondence may be addressed. E-mail: pawson{at}mshri.on.ca or bmayer{at}neuron.uchc.edu
Author contributions: G.M.R. and B.J.M. designed research; G.M.R. and S.A. performed research; S.G., N.Y.S., S.K.H., and T.P. contributed new reagents/analytic tools; G.M.R. analyzed data; and G.M.R. and B.J.M. wrote the paper.
Conflict of interest statement: No conflicts declared.
Abbreviations:

Abbreviations:

PDGF,

platelet-derived growth factor;

PDGFβR,

PDGF receptor;

SH,

Src homology;

MEF,

mouse embryonic fibroblast;

PI3K,

phosphatidylinositol 3-kinase;

Fak,

focal adhesion kinase.
Freely available online through the PNAS open access option.