ACVRL1
Serine/threonine-protein kinase receptor R3 is an enzyme that in humans is encoded by the "ACVRL1" gene. ACVRL1 is a receptor in the TGF beta signaling pathway. It is also known as activin receptor-like kinase 1, or ALK1. Function. This gene encodes a type I cell-surface receptor for the TGF-beta superfamily of ligands. It shares with other type I receptors a high degree of similarity in serine-threonine kinase subdomains, a glycine- and serine-rich region (called the GS domain) preceding the kinase domain, and a short C-terminal tail. The encoded protein, sometimes termed  ALK1, shares similar domain structures with other closely related ALK or activin receptor-like kinase proteins that form a subfamily of receptor serine/threonine kinases. Mutations in this gene are associated with hereditary hemorrhagic telangiectasia (HHT) type 2, also known as Rendu-Osler-Weber syndrome 2. Pathology. Germline mutations of ACVRL1 are associated with: Somatic mosaicism in ACVRL1 are associated with severe pulmonary arterial hypertension. ACVRL1 directly interacts with low-density lipoprotein (LDL), which implies that it might initiate the early phases of atherosclerosis. Abnormal activity of ACVRL1 has been found to be closely associated with idiopathic pulmonary arterial hypertension . Closely/family related kinases. ALK4 is ACVR1B, ALK7 is ACVR1C, and ALK5 is [part of] the TGF-β type I receptor.