MicroRNA 21 “Shapes” Vascular Smooth Muscle Behavior Through Regulating Tropomyosin 1

Abstract

Elucidating the complex mechanisms that govern vascular smooth muscle cell proliferation and migration has been a long-standing goal in vascular biology and medicine. In particular, refining strategies that mitigate these processes in the vascular smooth muscle compartment but do so in a cell-selective manner is of interest for therapeutic intervention in a variety of vascular pathologies. See accompanying article on page 2044 Recently, the function of microRNAs (miRNAs) in the setting of vascular disease has gained increasing interest at both the basic science and translational levels. miRNAs, a class of small noncoding RNA, function via binding “seed” sequences of target genes (usually but not exclusively in the 3′ untranslated region of the target mRNA), resulting in mRNA degradation or repression of translation. A single miRNA can act alone or in concert with others to regulate target genes and physiological and pathophysiological pathways and networks.1 Understanding their expression profiles, their basic function(s) in complex in vivo environments, and their contribution to disease pathogenesis in both experimental models and clinical samples is of fundamental importance. miRNA expression, regulation, and manipulation in diseases of the cardiac system and in cancer have been explored in great depth, and intervention strategies are being actively developed toward clinical goals. In contrast, the importance and function of …