Actin–myosin XI: an intracellular control network in plants

Actin is one of the three major cytoskeletal components in eukaryotic cells. Myosin XI is an actin-based motor protein in plant cells. Organelles are attached to myosin XI and translocated along the actin filaments. This dynamic actin–myosin XI system plays a major role in subcellular organelle transport and cytoplasmic streaming. Previous studies have revealed that myosin-driven transport and the actin cytoskeleton play essential roles in plant cell growth. Recent data have indicated that the actin–myosin XI cytoskeleton is essential for not only cell growth but also reproductive processes and responses to the environment. In this review, we have summarized previous reports regarding the role of the actin–myosin XI cytoskeleton in cytoplasmic streaming and plant development and recent advances in the understanding of the functions of actin–myosin XI cytoskeleton in Arabidopsis thaliana.