Potent inhibitor of the complement membrane attack complex (MAC) action. Acts by binding to the C8 and/or C9 complements of the assembling MAC, thereby preventing incorporation of the multiple copies of C9 required for complete formation of the osmolytic pore. This inhibitor appears to be species-specific. Involved in signal transduction for T-cell activation complexed to a protein tyrosine kinase. Defects in CD59 are the cause of CD59 deficiency (CD59D). Note: This description may include information from UniProtKB.
Cellular Component: anchored component of external side of plasma membrane; cell surface; compact myelin; endoplasmic reticulum membrane; endoplasmic reticulum-Golgi intermediate compartment membrane; extracellular space; focal adhesion; Golgi membrane; membrane; plasma membrane; sarcolemma; transport vesicle; vesicle
Molecular Function: complement binding; protein binding
Biological Process: blood coagulation; cell activation; cell surface receptor signaling pathway; COPII vesicle coating; ER to Golgi vesicle-mediated transport; negative regulation of activation of membrane attack complex; negative regulation of apoptosis; neutrophil degranulation; positive regulation of T cell proliferation; regulation of complement activation