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Title: Regulation of promyogenic signal transduction by cell-cell contact and adhesion

Abstract

Skeletal myoblast differentiation involves acquisition of the muscle-specific transcriptional program and morphological changes, including fusion into multinucleated myofibers. Differentiation is regulated by extracellular signaling cues, including cell-cell contact and adhesion. Cadherin and Ig adhesion receptors have been implicated in distinct but overlapping stages of myogenesis. N-cadherin signals through the Ig receptor Cdo to activate p38 MAP kinase, while the Ig receptor neogenin signals to activate FAK; both processes promote muscle-specific gene expression and myoblast fusion. M-cadherin activates Rac1 to enhance fusion. Specific Ig receptors (Kirre and Sns) are essential for myoblast fusion in Drosophila, also signaling through Rac, and vertebrate orthologs of Kirre and Sns have partially conserved function. Mice lacking specific cytoplasmic signaling factors activated by multiple receptors (e.g., Rac1) have strong muscle phenotypes in vivo. In contrast, mice lacking individual adhesion receptors that lie upstream of these factors have modest phenotypes. Redundancy among receptors may account for this. Many of the mammalian Ig receptors and cadherins associate with each other, and multivalent interactions within these complexes may require removal of multiple components to reveal dramatic defects in vivo. Nevertheless, it is possible that the murine adhesion receptors rate-limiting in vivo have not yet been identified or fully assessed.

Authors:
 [1]
  1. Department of Developmental and Regenerative Biology, Mount Sinai School of Medicine, New York, NY 10029 (United States)
Publication Date:
OSTI Identifier:
22209917
Resource Type:
Journal Article
Resource Relation:
Journal Name: Experimental Cell Research; Journal Volume: 316; Journal Issue: 18; Other Information: Copyright (c) 2010 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; DROSOPHILA; GENE REGULATION; IN VIVO; MICE; MORPHOLOGICAL CHANGES; MUSCLES; PHENOTYPE; RECEPTORS

Citation Formats

Krauss, Robert S., E-mail: Robert.Krauss@mssm.edu. Regulation of promyogenic signal transduction by cell-cell contact and adhesion. United States: N. p., 2010. Web. doi:10.1016/J.YEXCR.2010.05.008.
Krauss, Robert S., E-mail: Robert.Krauss@mssm.edu. Regulation of promyogenic signal transduction by cell-cell contact and adhesion. United States. doi:10.1016/J.YEXCR.2010.05.008.
Krauss, Robert S., E-mail: Robert.Krauss@mssm.edu. 2010. "Regulation of promyogenic signal transduction by cell-cell contact and adhesion". United States. doi:10.1016/J.YEXCR.2010.05.008.
@article{osti_22209917,
title = {Regulation of promyogenic signal transduction by cell-cell contact and adhesion},
author = {Krauss, Robert S., E-mail: Robert.Krauss@mssm.edu},
abstractNote = {Skeletal myoblast differentiation involves acquisition of the muscle-specific transcriptional program and morphological changes, including fusion into multinucleated myofibers. Differentiation is regulated by extracellular signaling cues, including cell-cell contact and adhesion. Cadherin and Ig adhesion receptors have been implicated in distinct but overlapping stages of myogenesis. N-cadherin signals through the Ig receptor Cdo to activate p38 MAP kinase, while the Ig receptor neogenin signals to activate FAK; both processes promote muscle-specific gene expression and myoblast fusion. M-cadherin activates Rac1 to enhance fusion. Specific Ig receptors (Kirre and Sns) are essential for myoblast fusion in Drosophila, also signaling through Rac, and vertebrate orthologs of Kirre and Sns have partially conserved function. Mice lacking specific cytoplasmic signaling factors activated by multiple receptors (e.g., Rac1) have strong muscle phenotypes in vivo. In contrast, mice lacking individual adhesion receptors that lie upstream of these factors have modest phenotypes. Redundancy among receptors may account for this. Many of the mammalian Ig receptors and cadherins associate with each other, and multivalent interactions within these complexes may require removal of multiple components to reveal dramatic defects in vivo. Nevertheless, it is possible that the murine adhesion receptors rate-limiting in vivo have not yet been identified or fully assessed.},
doi = {10.1016/J.YEXCR.2010.05.008},
journal = {Experimental Cell Research},
number = 18,
volume = 316,
place = {United States},
year = 2010,
month =
}
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