Vascular Gene Expression in Atherosclerotic Plaque-Prone Regions Analyzed by Representational Difference Analysis

Abstract
Objectives: Atherosclerotic plaques are known to develop and progress where the endothelium is subjected to turbulent blood flow. We have applied cDNA representational difference analysis (RDA) to study vascular gene expression in mouse aorta in a model for atherosclerosis. Methods:Gene expression profiles were investigated in plaque-prone and plaque-resistant localizations in the ascending aorta and arch in 8-week-old ApoE–/– and LDLR–/– mice. Total RNA was extracted and two rounds of subtraction were performed; the difference products were characterized in detail by shotgun cloning and analysis of more than 2,700 gene sequences. Results: The identified differentially expressed gene sequences include both genes with known involvement in vascular gene expression and genes previously not implicated in vascular processes. For example, CD36 and caveolin, previously reported for their participation in the progression of atherosclerosis, were found to have an increased expression in vessel localizations thought to be especially susceptible to plaque formation. Conclusions: This report provides new in vivo information of expressed genes that can be useful for further investigations of the molecular mechanisms in focal localization of atherosclerosis.