miR-15b induced by platelet-derived growth factor signaling is required for vascular smooth muscle cell proliferation

Abstract

The platelet-derived growth factor (PDGF) signaling pathway isessential for inducing a dedifferentiated state of vascular smoothmuscle cells (VSMCs). Activation of PDGF inhibits smoothmuscle cell (SMC)-specific gene expression and increases the rateof proliferation and migration, leading to dedifferentiation ofVSMCs. Recently, microRNAs have been shown to play a criticalrole in the modulation of the VSMC phenotype in response toextracellular signals. However, little is known about microRNAsregulated by PDGF in VSMCs. Herein, we identify microRNA-15b (miR-15b) as a mediator of VSMC phenotype regulationupon PDGF signaling. We demonstrate that miR-15b is inducedby PDGF in pulmonary artery smooth muscle cells and is criticalfor PDGF-mediated repression of SMC-specific genes. In addition,we show that miR-15b promotes cell proliferation. These resultsindicate that PDGF signaling regulates SMC-specific geneexpression and cell proliferation by modulating the expression ofmiR-15b to induce a dedifferentiated state in the VSMCs. [BMBReports 2013; 46(11): 550-554]

Keywords

• Cell proliferation
• Dedifferentiation
• microRNA
• PDGF
• Vascular smooth muscle cell