Published online August 13, 2007
doi:10.1083/jcb.200703060
The Journal of Cell Biology, Vol. 178, No. 4, 649-660
The Rockefeller University Press, 0021-9525 $30.00
© 2007 Gerhart et al.
Cells that express MyoD mRNA in the epiblast are stably committed to the skeletal muscle lineage
Jacquelyn Gerhart1,
Christine Neely1,
Justin Elder1,
Jessica Pfautz1,
Jordanna Perlman1,
Luis Narciso1,
Kersti K. Linask2,
Karen Knudsen3, and
Mindy George-Weinstein1
1 Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic Medicine, Philadelphia, PA 19131
2 University of South Florida, St. Petersburg, FL 33701
3 Lankenau Institute for Medical Research, Wynnewood, PA 19096
Correspondence to Mindy George-Weinstein: mindyw{at}pcom.edu
The epiblast of the chick embryo contains cells that express MyoD mRNA but not MyoD protein. We investigated whether MyoD-positive (MyoDpos) epiblast cells are stably committed to the skeletal muscle lineage or whether their fate can be altered in different environments. A small number of MyoDpos epiblast cells were tracked into the heart and nervous system. In these locations, they expressed MyoD mRNA and some synthesized MyoD protein. No MyoDpos epiblast cells differentiated into cardiac muscle or neurons. Similar results were obtained when MyoDpos cells were isolated from the epiblast and microinjected into the precardiac mesoderm or neural plate. In contrast, epiblast cells lacking MyoD differentiated according to their environment. These results demonstrate that the epiblast contains both multipotent cells and a subpopulation of cells that are stably committed to the skeletal muscle lineage before the onset of gastrulation. Stable programming in the epiblast may ensure that MyoDpos cells express similar signaling molecules in a variety of environments.
Abbreviations used in this paper: BMP, bone morphogenetic protein; CNS, central nervous system.

CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
Related Article
-
Cellular career decisions start early
- Ruth Williams
J. Cell Biol. 2007 178: 542.
[Full Text]
[PDF]