Endothelial Expression of Bone Morphogenetic Protein Receptor Type 1a is Required for Atrioventricular Valve Formation

Endocardial cushion formation is dependent on cell-specific expression of Bmpr1a. Our results suggest that Bmpr1a-mediated signaling is a crucial pathway involved in pathogenesis of atrioventricular septal and valve malformations, which are among the most common congenital heart defects in humans.