Abstract
Whereas light energy absorbed by photosystem II (PSII) is partially used for photosynthetic electron transfer and carbon dioxide fixation, a large proportion of the energy is dissipated as heat. This thermal dissipation, which can be detected as non-photochemical quenching (NPQ) of chl fluorescence, depends upon xanthophyll cycle and PsbS protein. The rate of the thermal dissipation in PSII is stoichiometrically dependent on PsbS amount, suggesting that the regulation of expression level of psbS can control the thermal dissipation. In this study, we have made the rice tansformants with psbS gene-silenced by RNA interference (RNAi) to clarify the relation between the expression of psbS and NPQ formation. We produced five types of transformants using the RNAi vectors for coding sequence and the UTR of rice psbS. We will report the relation between the expression levels of psbS and the electron transport activities around PSII in these transgenic rice plants.
