Lipid Interactions of Cytoskeletal Proteins

Abstract

At least 18 different cytoskeletal proteins have been shown to interact in vitro with, and in some cases are regulated by, specific membrane lipids, mostly phosphoinositides, whose synthesis is themselves regulated by extracellular signals. These lipid interactions are mediated by structurally diverse specific binding sites. Lipid interactions can serve to target proteins, such as spectrin, myosin X, dynamin, or annexin 2, to the plasma membrane or inactivate processes counteracting actin polymerization and stimulate proteins, such as Wiskott–Aldrich syndrome protein (WASP), involved in nucleating actin polymerization. In other cases (ezrin, talin), phosphoinositides serve to activate proteins involved in actin‐membrane linkage. Such interactions may occur highly localized in lipid rafts.