Abstract
The continuous and rapid movement of organelles and endosomal vesicles, which is termed cytoplasmic streaming, is found within plant cells. The cytoplasmic streaming has been studied for two centuries and is believed to be driven by the acto-myosin cytoskeleton. However, the molecular mechanism underlying the cytoplasmic streaming in plants is unknown. In order to elucidate the mechanism and physiological function of the cytoplasmic streaming, we focused on the myosin XI molecules of Arabidopsis thriana which has 13 homologs of myosin XI, and isolated 13 knockout mutants for each gene. However, all of the single mutants did not show any abnormal phenotypes. We further generated double mutants of myosin XI homologs. Finally, we found that one of the double mutants showed a unique phenotype, suggesting that myosin genes have the redundant functions.
