Bone morphogenetic protein receptor (BMPR) (BMPR)

Bone morphogenetic protein (BMP) receptors are transmembrane serine/threonine kinases belonging to the transforming growth factor-beta (TGF-beta) superfamily. They function as heterotetrameric complexes consisting of two Type I receptors (such as ALK1, ALK2, ALK3, or ALK6) and two Type II receptors (such as BMPR2, ACTR2A, or ACTR2B). Upon ligand binding, the Type II receptor phosphorylates the Type I receptor, which then activates downstream SMAD1/5/8 signaling pathways to regulate gene expression (UniProt P36894, Q13873). These receptors are essential for diverse biological processes, including osteogenesis, chondrogenesis, and vascular homeostasis. Mutations in these receptors are linked to significant human diseases; for instance, gain-of-function mutations in ACVR1 (ALK2) cause Fibrodysplasia Ossificans Progressiva (FOP), while loss-of-function mutations in BMPR2 are a primary cause of hereditary Pulmonary Arterial Hypertension (PAH) (PubMed PMID: 16633345, 11017076). Therapeutic strategies include small molecule kinase inhibitors like momelotinib to block overactive signaling and ligand traps like sotatercept to rebalance the signaling environment in vascular and hematologic diseases (FDA 2024).

Other names

BMP type I and type II receptorsBone morphogenetic protein type 1 receptorBone morphogenetic protein type 2 receptorActivin receptor-like kinase (ALK)ACVR1BMPR1ABMPR1BBMPR2ACVRL1

Small molecule inhibition of the intracellular serine/threonine kinase domain of type I receptors (e.g., ALK2) or ligand sequestration using decoy receptors (ligand traps) to prevent receptor activation and subsequent SMAD signaling.