Abstract
We previously showed that cyclobutane pyrimidine dimer (CPD) photolyase is deficient in UVB-sensitive rice, and that the CPD photolyase deficiency might result from a mutation of CPD photolyase. The CPD photolyase activity in UVB sensitive Surjamkhi (Indica) was significantly lower than that in UVB resistant Sasanishiki (Japonica). There were two variations at codon 126 and 296 in the deduced amino acid sequence of CPD photolyase between both cultivars. We confirmed that these mutations affected the CPD photolyase activity. To test whether the difference in the CPD photolyase activity causes the difference in UVB sensitivity in rice, we carried out the genetic analysis of correlation between UVB-sensitivity and genotype of CPD photolyase using F2 and F3 plants generated by reciprocally crossing Sasanishiki and Surjamkhi. As a results, we found that UVB sensitivity and the activity of photolyase were tightly linked in rice plant.
