Molecular cloning and characterization of thepsbL andpsbJ genes for photosystem II fromPanax ginseng

We have cloned and characterized two genes for Photosystem II from chloroplasts ofPanax ginseng. These genes,psbl andpsbJ, comprise 117 and 123 nucleotides, respectively. When compared with monocots, dicots, or liverwort, the overall amino acid sequence identity of the former is >97%, whereas that of the latter is approximately 95 to 100%. Southern blot analysis revealed that a single copy of each gene exists in the chloroplast genome. Our Northern blot analysis indicated thatpsbL andpsb) are co-transcribed as a polycistron and are not subjected to further processing into smaller transcripts. We also determined that varying daylight intensities (5,10, 20, or 100%) did not significantly change the level ofin vivo accumulation ofpsbLJ transcript