Abstract
UVB can damage DNA by causing formation of cyclobutane pyrimidine dimer (CPD). Photoreactivation mediated by an enzyme, photolyase, is the major pathway for repairing CPD in plants. Although plant cell has different genome in each nuclei, chloroplast and mitochondria, it is unclear whether CPD photoreactivation is involved in each organelle. We previously reported that the UVB-induced CPD levels on each organelle genome decreased dependently by exposure of blue irradiation. These results suggested that CPD photolyase could function in each organelle in rice. In this study, in order to verify this suggestion, we compared the CPD photorepair capacity in each organelle among two rice strains (Sasanishiki and Surjamkhi) and CPD photolyase transgenic plants. As a result, the CPD photorepair capacity in each organelle was faster in Sasanishiki than that in Surjamkhi, and was not detected in antisense transgenic plant. Thus, CPD photolyase functions in nuclei, chloroplast and mitochondria in rice.
