A pair of short RNA strands known as microRNAs may represent a therapeutic target for some forms of arterial disease.
The smooth muscle cells of arteries can switch between two phenotypes: contractile and synthetic; accumulation of the latter is associated with atherosclerosis. In a search for microRNAs that might control this switch in mice, Thomas Braun and Thomas Boettger at the Max Planck Institute for Heart and Lung Research in Bad Nauheim, Germany, and their collaborators came across two microRNAs — 143 and 145 — that are expressed in smooth muscle cells throughout the body (coloured blue in the heart pictured below). Their sequences are necessary for normal development of contractile smooth muscle cells.
The researchers performed an in vivo analysis of the proteins regulated by the microRNAs. Among them was ACE, a protein targeted by a major class of blood-pressure medication.