Bone morphogenetic proteins (BMPs) are secreted signaling proteins, many of which are involved in various developmental processes, in addition to bone formation. Activation of BMP type I receptors, also known as activin receptor-like kinases (ALK1-7), leads to the assembly of SMAD complexes, which translocate to the nucleus to induce transcriptional activation important for normal development and tissue repair. LDN-214117 is a selective BMP type I receptor kinase ALK1 and ALK2 inhibitor (IC50s = 24 nM for each). It demonstrates preference for ALK1 and ALK2 over ALK3 (IC50 = 1.17 μM) and other related activin and TGF-β type I receptors (IC50s = 3, 0.1, and 16 μM for ALK5, BMP6, and TGF-β, respectively).
