Requirement of an intermediate gene expression for biphasic ERK1/2 activation in thrombin-stimulated vascular smooth muscle cells.

ABSTRACT: The expression of contractile proteins in vascular smooth muscle cells is controlled by still poorly defined mechanisms. A thrombin-inducible expression of smooth muscle-specific alpha-actin and myosin heavy chain requires transactivation of the epidermal growth factor (EGF) receptor and a biphasic activation of ERK1/2. Here we demonstrate that the sustained second phase of ERK1/2 phosphorylation requires de novo RNA and protein synthesis. Depolymerization of the actin cytoskeleton by cytochalasin D or disruption of transit between the endoplasmic reticulum and the Golgi apparatus by brefeldin A prevented the second phase of ERK1/2 phosphorylation. We thus conclude that synthesis and trafficking of a plasma membrane-resident protein may be critical intermediates. Analysis of the expression

SUBMITTER: Sastre AP 

PROVIDER: S-EPMC3258847 | biostudies-literature | 2008 Sep

REPOSITORIES: biostudies-literature