Abstract
Dinoflagellates are important members of aquatic ecosystem: some species bloom as harmful red tides and other species flourish as photosymbionts of reef-building corals. The peridinin-containing dinoflagellates with minicircular plastid genome originated from secondary endosymbiosis involving a red algal lineage, like diatoms and brown algae. Each minicircle (2-10 kb) has essentially one gene. Most genes, which are generally plastid genes in algae and plants, are nuclear genes in dinoflagellates and only a limited number of genes are kept in minicircular plastid genome. Our previous study showed that low-copy-number of multiple variants of the gene psbA and psbD coexist with the ordinary genes in minicircles of Alexandrium spp. These variants, as well as ordinary psbA, are edited after transcription. In this study, we characterized the structure of photosystem II of dinoflagellate based on the predicted amino acids sequences and the secondary structures of several subunits consist of photosystem II.
