Definition:

Cell membrane-cytoskeleton-associated protein that plays a role in the regulation of actin polymerization at the barbed end of actin filaments. Prevents F-actin heterodimeric capping protein (CP) activity at the leading edges of migrating cells, and hence generates uncapped barbed ends and enhances actin polymerization. Plays a role in cell protrusion formations; involved in cell polarity, lamellipodial assembly, membrane ruffling and macropinosome formations. Involved as well in cell migration and invadopodia formation during wound healing. Required for CD28-mediated stimulation of NF-kappa-B signaling, involved in naive T cells activation, maturation into T memory cells, and differentiation into T helper and T regulatory cells.