Arginylation of beta-actin regulates actin cytoskeleton and cell motility.

Posttranslational arginylation is critical for mouse embryogenesis, cardiovascular development, and angiogenesis, but its molecular effects and the identity of proteins arginylated in vivo are unknown. We found that beta-actin was arginylated in vivo to regulate actin filament properties, beta-actin localization, and lamella formation in motile cells. Arginylation of beta-actin apparently represents a critical step in the actin N-terminal processing needed for actin functioning in vivo. Thus, posttranslational arginylation of a single protein target can regulate its intracellular function, inducing global changes on the cellular level, and may contribute to cardiovascular development and angiogenesis.