Abstract
Chloroplasts are centripetally or centrifugally arranged in bundle sheath cells (BSC) of C4 plants. The intracellular arrangement of BSC chloroplasts is acquired during cell maturation and can be re-established after disturbance by centrifugation. Therefore, it is expected that BSC chloroplasts possess molecular mechanisms to recognize their intracellular positions and move to certain positions. In this study, we investigated the effects of various inhibitors to re-establishment of centripetally arrangement of BSC chloroplasts in finger millet (Eleusine coracana), an NAD-ME-type C4 plant, after centrifugal treatment. Although microtuble polymerization inhibitor, colchicine, was not effective, actin polymerization inhibitors, cytochalasin B and latrunculin B, inhibited the re-establishment. Myosin ATPase inhibitor BDM and cycloheximide also showed inhibitory effects. These results suggested that de novo protein synthesis and myosin-actin system have important roles in intracellular arrangement of BSC chloroplasts.
