Abstract
Chloroplasts are partially mobilized to the vacuole via RCBs by autophagy. We have analyzed factors affecting the RCB-creation in Arabidopsis excised leaves. We suggested that the sugar contents in leaves were the main factors affecting the RCB-creation, and the presence of mechanism specifically controlling the RCB-creation in autophagy. In this study, we analyzed the RCB-creation in leaves of starch-less mutants (pgm, adg1) and starch-excess mutants (sex1, mex1). In continuous illumination, the RCB-creation was accelerated in leaves of starch-less mutants. There were more starch content and lower creation of RCBs in starch-excess mutants than wild-types. In the condition of 14-hour photoperiod, we investigated the RCB-creation from highly expanding to senescent stages. The maximum number of RCBs in each stage was significantly higher in starch-less mutants and lower in starch-excess mutants compared to wild-types. These results indicate that the starch metabolism have a critical role in the RCB-creation.
