QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

Vol. 16, Issue 9, 4280-4293, September 2005

This Article Full Text Full Text (PDF) All Versions of this Article: E05-02-0112v1 16/9/4280    most recent Alert me when this article is cited Alert me if a correction is posted Services 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 Stone, M. R. Articles by Bloch, R. J. Search for Related Content PubMed PubMed Citation Articles by Stone, M. R. Articles by Bloch, R. J.

Specific Interaction of the Actin-binding Domain of Dystrophin with Intermediate Filaments Containing Keratin 19

Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201

Submitted February 10, 2005; Revised June 2, 2005; Accepted June 28, 2005
Monitoring Editor: Guido Guidotti

Cytokeratins 8 and 19 concentrate at costameres of striated muscle and copurify with the dystrophin-glycoprotein complex, perhaps through the interaction of the cytokeratins with the actin-binding domain of dystrophin. We overexpressed dystrophin's actin-binding domain (Dys-ABD), K8 and K19, as well as closely related proteins, in COS-7 cells to assess the basis and specificity of their interaction. Dys-ABD alone associated with actin microfilaments. Expressed with K8 and K19, which form filaments, Dys-ABD associated preferentially with the cytokeratins. This interaction was specific, as the homologous ABD of I-spectrin failed to interact with K8/K19 filaments, and Dys-ABD did not associate with desmin or K8/K18 filaments. Studies in COS-7 cells and in vitro showed that Dys-ABD binds directly and specifically to K19. Expressed in muscle fibers in vivo, K19 accumulated in the myoplasm in structures that contained dystrophin and spectrin and disrupted the organization of the sarcolemma. K8 incorporated into sarcomeres, with no effect on the sarcolemma. Our results show that dystrophin interacts through its ABD with K19 specifically and are consistent with the idea that cytokeratins associate with dystrophin at the sarcolemma of striated muscle.

Abbreviations used: ABD, actin-binding domain; Dys-ABD, actin-binding domain of dystrophin; K8, cytokeratin 8; K19, cytokeratin 19; hK19, human cytokeratin 19; PBS, phosphate-buffered saline; RU, resonance unit.

^* Present address: Aeras Global TB Vaccine Foundation, Bethesda, MD, 20814.

Address correspondence to: Robert J. Bloch (rbloch{at}umaryland.edu).

This article has been cited by other articles:

				M. R. Stone, A. O'Neill, R. M. Lovering, J. Strong, W. G. Resneck, P. W. Reed, D. M. Toivola, J. A. Ursitti, M. B. Omary, and R. J. Bloch Absence of keratin 19 in mice causes skeletal myopathy with mitochondrial and sarcolemmal reorganization J. Cell Sci., November 15, 2007; 120(22): 3999 - 4008. [Abstract] [Full Text] [PDF]

				G. B. Banks, P. Gregorevic, J. M. Allen, E. E. Finn, and J. S. Chamberlain Functional capacity of dystrophins carrying deletions in the N-terminal actin-binding domain Hum. Mol. Genet., September 1, 2007; 16(17): 2105 - 2113. [Abstract] [Full Text] [PDF]

				G. A. Rezniczek, P. Konieczny, B. Nikolic, S. Reipert, D. Schneller, C. Abrahamsberg, K. E. Davies, S. J. Winder, and G. Wiche Plectin 1f scaffolding at the sarcolemma of dystrophic (mdx) muscle fibers through multiple interactions with {beta}-dystroglycan J. Cell Biol., March 26, 2007; 176(7): 965 - 977. [Abstract] [Full Text] [PDF]