Annexins are a multigene family of Ca++-regulated phospholipid-binding proteins. They serve as membrane-membrane, or membrane-cytoskeleton linkers, and regulate the formation of lipid domains in the plasma membrane. The name annexin derives from the fact that initial studies suggested that acidic membrane phospholipids and Ca++ annexed, or recruited, special cytosolic proteins into a membrane-interacting ternary complex. Annexins possess a series of unique 70 amino acid annexin-repeat modules that form a curved disk and allow for the creation of an intercessory complex between plasma membrane and cytofilaments.