Leukocyte surface antigen CD47 (also known as integrin-associated protein, IAP) is a widely expressed membrane protein with multiple functions in immunological and neuronal processes. For example, CD47-induces caspase-independent cell death which may be mediated by cytoskeleton reorganisation []. In red blood cells, CD47 acts like a marker of self by ligating the macrophage inhibitory receptor signal regulatory protein alpha []. The protein can also act as a thrombospondin receptor [].This entry also includes a group of CD-47-like proteins found in poxviruses (Poxviridae) such as protein A38 [].
CD47 was originally identified as integrin-associated protein (IAP). It is a transmembrane glycoprotein that possesses an immunoglobulin variable (IgV) like N-terminal domain, five transmembrane domains and an alternatively spliced C terminus. It functions as a marker of self on erythrocytes, and likely also on other cells, by binding to the inhibitory receptor SIRPalpha []. CD47-induces caspase-independent cell death may be mediated by cytoskeleton reorganisation []. The protein can also act as a thrombospondin receptor [].This entry represents the IgV domain of of CD47. The interaction of CD47 with integrins is dependent on its IgV and transmembrane domains. The IgV domain and transmembrane domain of CD47 have also been found to be sufficient for the association with actin [].
