Abstract
In order to elucidate the physiological role of PsbP protein, one of extrinsic lumenal subunits of the oxygen-evolving complex of photosystem II in higher plants and green algae, we have generated a series of PsbP-silenced transgenic tobacco plants by RNA interference (RNAi) method. In Nicotiana tabacum, PsbP proteins are nuclear-encoded by four isogenes, which are divided into two groups (group-I; 1A and 5B: group-II; 2AF and 3F). We used the coding sequence of 2AF, the 3'- UTR of 1A and the 3'-UTR of 2AF to differentially trigger RNAi. The dsRNA of the 3'-UTR was shown to induce the group-specific RNAi [Ifuku et al. (2003) BBB, 67, 107-113]. On the other hand, the dsRNA of the coding region, which is highly conserved among the family, was shown to effectively silence the expression of all members of the family. Physiological and biochemical characterization of these PsbP-silenced transgenic plants is in progress.
