Baculoviral inhibitor of apoptosis repeat-containing 5 or BIRC5 (also known as Survivin) is a protein encoded by the BIRC5 gene in humans. It is a novel cell surface receptor for factor Xa, potentially implicated in protease-dependent cellular effector functions. It is a transmembrane glycoprotein receptor for factor Xa th at contributes to cell surface assembly of proteolytic activities and leukocyte mitogenesis. It is dynamically modulated by mRNA splicing. It is an inhibitor of apoptosis and is expressed in various malignancies.
