May mediate accelerated ATP-independent bidirectional transbilayer migration of phospholipids upon binding calcium ions that results in a loss of phospholipid asymmetry in the plasma membrane. May play a central role in the initiation of fibrin clot formation, in the activation of mast cells and in the recognition of apoptotic and injured cells by the reticuloendothelial system.
Subcellular locations: Membrane
Expressed in heart, brain, placenta, lung, liver, kidney, pancreas, spleen, thymus, prostate, testis, uterus, small intestine and colon. Not detected in peripheral blood lymphocytes.