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.
Isoform 1 has no prospholipid scramblase activity, due to the lack of a N-terminal proline-rich domain.
Subcellular locations: Membrane
Subcellular locations: Nucleus
Expression of isoform 1 seems restricted to testis.