Abstract
The degradation of chloroplast proteins in senescent leaves is important for nutrients remobilization. The key factors, however, are not yet known. Recently, we have found that one of the chloroplastic aspartic protease, i.e., CND41 in tobacco, has important role of degradation of chloroplast proteins, especially Rubisco, in senescent leaves. Here, we report the physiological characterization of two aspartic proteases (At5g10770 and At5g10760), which are most homologous to tobacco CND41 in Arabidopsis in senescence. Both At5g10760 and At5g10770 showed enhanced expression under nitrogen-starvation and high sucrose conditions, suggesting the possible involvement of CND41 homologues in senescence. Several transgenic plants with ectopic expression or RNA silencing of each CND41 homologue were produced. Chloroplastic protein degradation in these transgenic Arbidopsis in senescence will be discussed.
