Cardiac malformations due to aberrant development of the atrioventricular (AV) valves are
among the most common forms of congenital heart diseases. Normally, heart valve
mesenchyme is formed from an endothelial to mesenchymal transition (EMT) of endothelial
cells of the endocardial cushions. Yes-associated protein 1 (YAP1) has been reported to
regulate EMT in vitro, in addition to its known role as a major regulator of organ size and cell
proliferation in vertebrates, leading us to hypothesize that YAP1 is required for heart valve …