Published 1 August 2005. doi:10.1083/jcb.200502090
The Rockefeller University Press, 0021-9525 $8.00
JCB, Volume 170, Number 3, 465-476
Essential role of CIB1 in regulating PAK1 activation and cell migration
Tina M. Leisner1,2,
Mingjuan Liu1,
Zahara M. Jaffer4,
Jonathan Chernoff4, and
Leslie V. Parise1,2,3
1 Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
2 Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
3 Carolina Cardiovascular Biology Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
4 Tumor Cell Biology Program, Fox Chase Cancer Center, Philadelphia, PA 19111
Correspondence to Leslie V. Parise: parise{at}med.unc.edu
p21-activated kinases (PAKs) regulate many cellular processes, including cytoskeletal rearrangement and cell migration. In this study, we report a direct and specific interaction of PAK1 with a 22-kD Ca2+-binding protein, CIB1, which results in PAK1 activation both in vitro and in vivo. CIB1 binds to PAK1 within discrete regions surrounding the inhibitory switch domain in a calcium-dependent manner, providing a potential mechanism of CIB1-induced PAK1 activation. CIB1 overexpression significantly decreases cell migration on fibronectin as a result of a PAK1-and LIM kinasedependent increase in cofilin phosphorylation. Conversely, the RNA interferencemediated depletion of CIB1 increases cell migration and reduces normal adhesion-induced PAK1 activation and cofilin phosphorylation. Together, these results demonstrate that endogenous CIB1 is required for regulated adhesion-induced PAK1 activation and preferentially induces a PAK1-dependent pathway that can negatively regulate cell migration. These results point to CIB1 as a key regulator of PAK1 activation and signaling.
Abbreviations used in this paper: ca, constitutively active; DN, dominant negative; FN, fibronectin; HEK, human embryonic kidney; IS, inhibitory switch; kd, kinase dead; KI, kinase inhibitor; LIMK, Lin-11/Isl-1/Mec-3 kinase; MEF, mouse embryo fibroblast; NTA, nitrilotriacetic acid; PAK, p21-activated kinase; PBD, p21-binding domain; REF, rat embryo fibroblast; si, short inhibitory.

CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
Related Article
-
Two-step adhesion
- Rabiya S. Tuma
J. Cell Biol. 2005 170: 335.
[Full Text]
[PDF]
This article has been cited by other articles:
-
Zayed, M. A., Yuan, W., Leisner, T. M., Chalothorn, D., McFadden, A. W., Schaller, M. D., Hartnett, M. E., Faber, J. E., Parise, L. V.
(2007). CIB1 Regulates Endothelial Cells and Ischemia-Induced Pathological and Adaptive Angiogenesis. Circ. Res.
101: 1185-1193
[Abstract]
[Full Text]
-
Lee, S.-H., Kunz, J., Lin, S.-H., Yu-Lee, L.-y.
(2007). 16-kDa Prolactin Inhibits Endothelial Cell Migration by Down-Regulating the Ras-Tiam1-Rac1-Pak1 Signaling Pathway. Cancer Res.
67: 11045-11053
[Abstract]
[Full Text]
-
Yuan, W., Leisner, T. M., McFadden, A. W., Clark, S., Hiller, S., Maeda, N., O'Brien, D. A., Parise, L. V.
(2006). CIB1 Is Essential for Mouse Spermatogenesis. Mol. Cell. Biol.
26: 8507-8514
[Abstract]
[Full Text]
-
Safholm, A., Leandersson, K., Dejmek, J., Nielsen, C. K., Villoutreix, B. O., Andersson, T.
(2006). A Formylated Hexapeptide Ligand Mimics the Ability of Wnt-5a to Impair Migration of Human Breast Epithelial Cells. J. Biol. Chem.
281: 2740-2749
[Abstract]
[Full Text]
-
Yuan, W., Leisner, T. M., McFadden, A. W., Wang, Z., Larson, M. K., Clark, S., Boudignon-Proudhon, C., Lam, S. C.-T., Parise, L. V.
(2006). CIB1 is an endogenous inhibitor of agonist-induced integrin {alpha}IIb{beta}3 activation. J. Cell Biol.
172: 169-175
[Abstract]
[Full Text]