|
|
|
|
A more recent version of this article appeared on January 1, 2008 Originally published as MBC in Press, 10.1091/mbc.E07-01-0008 on November 7, 2007
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Submitted on January 8, 2007
Revised on October 5, 2007
Accepted on October 12, 2007



Department of Biology and
Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3280; *Department of Biology, Randolph-Macon College, Ashland, VA 23005
Monitoring Editor: Jean Schwarzbauer
Signaling by the nonreceptor tyrosine kinase Abelson (Abl) plays key roles in normal development, while its inappropriate activation helps trigger the development of several forms of leukemia. Abl is best known for its roles in axon guidance but Abl and its relatives also help regulate embryonic morphogenesis in epithelial tissues. Here we explore the role of regulation of Abl kinase activity during development. We first compare the subcellular localization of Abl protein and of active Abl, using a phospho-specific antibody, providing a catalogue of places where Abl is activated. Next we explore the consequences for morphogenesis of overexpressing wild-type Abl or expressing the activated form found in leukemia, Bcr-Abl. We find dose-dependent effects of elevating Abl activity on morphogenetic movements such as head involution and dorsal closure, on cell shape changes, on cell protrusive behavior, and on the organization of the actin cytoskeleton. Most of the effects of Abl activation parallel those caused by reduction in function of its target Enabled. Abl activation leads to changes in Enabled phosphorylation and localization, suggesting a mechanism of action. These data provide new insights into how regulated Abl activity helps direct normal development and into possible biological functions of Bcr-Abl.
These two authors contributed equally to this work.
Address correspondence to:
Mark Peifer (peifer{at}unc.edu)