Efficient, Retro Viral-Mediated Expression Of GFP Fusion Proteins as Inhibitors of Intracellular Signal Transduction Pathways: A Case Study

Abstract

A variety of extracellular signals, including hormones, neurotransmitters, growth factors and cytokines, are capable of activating vascular smooth muscle cells (VSMC). These can modulate the VSMC phenotype, which underlies the progression of vascular diseases. We study gene expression control responses in VSMC that are regulated by different classes of cell surface receptors. Taken as simpler model systems for the pleiotropic sensitivity of VSMC to extracellular stimuli, we focus on understanding the elements of intracellular signal transduction pathways involved in controlling gene expression. In particular, we are interested in identifying signaling elements that can be activated by multiple classes of cell surface receptors.Previous studies had supported both a role of protein kinase A (PKA) activity and transcriptional induction of an unknown factor in control of ATI angiotensin receptor gene expression in VSMC (1). The mRNA from this gene is down-regulated by a variety of extracellular stimuli, and we hypothesized that stimulation of PKA by several classes of receptors might explain the apparently pleiotropic nature of ATI-receptor down regulation.