QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online 29 June 2004
doi: 10.1242/jcs.01216

This Article Figures Only Full Text Full Text (PDF) All Versions of this Article: jcs.01216v1 jcs.01216v2 117/16/3593    most recent Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Li, Y. Articles by Lin, J. J. C. Search for Related Content PubMed PubMed Citation Articles by Li, Y. Articles by Lin, J. J. C. Social Bookmarking                         What's this?

Caldesmon mutant defective in Ca²⁺-calmodulin binding interferes with assembly of stress fibers and affects cell morphology, growth and motility

Department of Biological Sciences, University of Iowa, 340 Biology Building East, Iowa City, IA 52242-1324, USA

^* Author for correspondence (e-mail: jim-lin{at}uiowa.edu)

Accepted 10 March 2004

Despite intensive in vitro studies, little is known about the regulation of caldesmon (CaD) by Ca²⁺-calmodulin (Ca²⁺-CaM) in vivo. To investigate this regulation, a mutant was generated of the C-terminal fragment of human fibroblast CaD, termed CaD39-AB, in which two crucial tryptophan residues involved in Ca²⁺-CaM binding were each replaced with alanine. The mutation abolished most CaD39-AB binding to Ca²⁺-CaM in vitro but had little effect on in vitro binding to actin filaments and the ability to inhibit actin/tropomyosin-activated heavy meromyosin ATPase. To study the functional consequences of these mutations in vivo, we transfected an expression plasmid carrying CaD39-AB cDNA into Chinese hamster ovary (CHO) cells and isolated several clones expressing various amounts of CaD39-AB. Immunofluorescence microscopy revealed that mutant CaD39-AB was distributed diffusely throughout the cytoplasm but also concentrated at membrane ruffle regions. Stable expression of CaD39-AB in CHO cells disrupted assembly of stress fibers and focal adhesions, altered cell morphology, and slowed cell cycle progression. Moreover, CaD39-AB-expressing cells exhibited motility defects in a wound-healing assay, in both velocity and the persistence of translocation, suggesting a role for CaD regulation by Ca²⁺-CaM in cell migration. Together, these results demonstrate that CaD plays a crucial role in mediating the effects of Ca²⁺-CaM on the dynamics of the actin cytoskeleton during cell migration.

Key words: Actin-bundling activity, Actin-stabilizing activity, Caldesmon, Focal adhesion, Wound-healing assay, Lamellipodium

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				F. Kantawong, R. Burchmore, N. Gadegaard, R. O. C. Oreffo, and M. J. Dalby Proteomic analysis of human osteoprogenitor response to disordered nanotopography J R Soc Interface, November 6, 2009; 6(40): 1075 - 1086. [Abstract] [Full Text] [PDF]

				T. Mayanagi, T. Morita, K. Hayashi, K. Fukumoto, and K. Sobue Glucocorticoid Receptor-mediated Expression of Caldesmon Regulates Cell Migration via the Reorganization of the Actin Cytoskeleton J. Biol. Chem., November 7, 2008; 283(45): 31183 - 31196. [Abstract] [Full Text] [PDF]

				K. Thorsen, K. D. Sorensen, A. S. Brems-Eskildsen, C. Modin, M. Gaustadnes, A.-M. K. Hein, M. Kruhoffer, S. Laurberg, M. Borre, K. Wang, et al. Alternative Splicing in Colon, Bladder, and Prostate Cancer Identified by Exon Array Analysis Mol. Cell. Proteomics, July 1, 2008; 7(7): 1214 - 1224. [Abstract] [Full Text] [PDF]

				P. A. Fowler, N. J. Dora, H. McFerran, M. R. Amezaga, D. W. Miller, R. G. Lea, P. Cash, A. S. McNeilly, N. P. Evans, C. Cotinot, et al. In utero exposure to low doses of environmental pollutants disrupts fetal ovarian development in sheep Mol. Hum. Reprod., May 1, 2008; 14(5): 269 - 280. [Abstract] [Full Text] [PDF]

				S. E. McGowan, A. J. Holmes, R. P. Mecham, and T. M. Ritty Arg-Gly-Asp-Containing Domains of Fibrillins-1 and -2 Distinctly Regulate Lung Fibroblast Migration Am. J. Respir. Cell Mol. Biol., April 1, 2008; 38(4): 435 - 445. [Abstract] [Full Text] [PDF]

				S. Choi, E. A. Gustafson-Wagner, Q. Wang, S. M. Harlan, H. W. Sinn, J. L.-C. Lin, and J. J.-C. Lin The Intercalated Disc Protein, mXin{alpha}, Is Capable of Interacting with -Catenin and Bundling Actin Filaments J. Biol. Chem., December 7, 2007; 282(49): 36024 - 36036. [Abstract] [Full Text] [PDF]

				T. Morita, T. Mayanagi, and K. Sobue Dual roles of myocardin-related transcription factors in epithelial mesenchymal transition via slug induction and actin remodeling J. Cell Biol., December 3, 2007; 179(5): 1027 - 1042. [Abstract] [Full Text] [PDF]

				R. Eves, B. A. Webb, S. Zhou, and A. S. Mak Caldesmon is an integral component of podosomes in smooth muscle cells J. Cell Sci., May 1, 2006; 119(9): 1691 - 1702. [Abstract] [Full Text] [PDF]

				M. E. Cuomo, A. Knebel, G. Platt, N. Morrice, P. Cohen, and S. Mittnacht Regulation of Microfilament Organization by Kaposi Sarcoma-associated Herpes Virus-cyclin{middle dot}CDK6 Phosphorylation of Caldesmon J. Biol. Chem., October 28, 2005; 280(43): 35844 - 35858. [Abstract] [Full Text] [PDF]