|
|
|
|
|
|
|
||
J. Cell Biol.,
Volume 141, Number 7, June 29, 1998 1647-1658
* Department of Molecular Biology, Holland Laboratory, American Red Cross, Rockville, Maryland 20855; and FGF regulates both cell migration and proliferation by receptor-dependent induction of immediate-early gene expression and tyrosine phosphorylation of
intracellular polypeptides. Because little is known
about the disparate nature of intracellular signaling pathways, which are able to discriminate between cell
migration and proliferation, we used a washout strategy
to examine the relationship between immediate-early
gene expression and tyrosine phosphorylation with respect to the potential of cells either to migrate or to initiate DNA synthesis in response to FGF-1. We demonstrate that transient exposure to FGF-1 results in a
significant decrease in Fos transcript expression and a
decrease in tyrosine phosphorylation of the FGFR-1,
p42mapk, and p44mapk. Consistent with these biochemical
effects, we demonstrate that attenuation in the level of
DNA synthesis such that a 1.5-h withdrawal is sufficient
to return the population to a state similar to quiescence. In contrast, the level of Myc mRNA, the activity of Src,
the tyrosine phosphorylation of cortactin, and the FGF-1-induced redistribution of cortactin and F-actin were
unaffected by transient FGF-1 stimulation. These biochemical responses are consistent with an implied uncompromised migratory potential of the cells in response to growth factor withdrawal. These results
suggest a correlation between Fos expression and the
mitogen-activated protein kinase pathway with initiation of DNA synthesis and a correlation between high
levels of Myc mRNA and Src kinase activity with the
regulation of cell migration.
Center for
Molecular Medicine, Maine Medical Center Research Institute, S. Portland, Maine 04106
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
