Annexin IV /placental anticoagulant protein II (ANX4) is a member of the annexin or lipocortin family of calcium-dependent phospholipid binding proteins,and is located at 2p13. Although their functions are still not clearly defined,several members of the annexin family have been implicated in membrane-related events along exocytotic and endocytotic pathways. ANX4 shares 45 to 59% identity with other members and possibly interacts with ATP. ANX4 has in vitro anticoagulant activity and also inhibits phospholipase A2 activity. ANX4 is almost exclusively expressed in epithelial cells.