This gene encodes a platelet membrane glycoprotein of the immunoglobulin superfamily. The encoded protein is a receptor for collagen and plays a critical role in collagen-induced platelet aggregation and thrombus formation. The encoded protein forms a complex with the Fc receptor gamma-chain that initiates the platelet activation signaling cascade upon collagen binding. Mutations in this gene are a cause of platelet-type bleeding disorder-11 (BDPLT11). Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Dec 2011]