Abstract
We have previously reported that chloroplastic (chl) CuZn-SOD gene of the alga Spirogyra contained extra intron in the coding region of the transit peptide and the location was identical site of the first intron in 5'-UTR of the plant cytosolic (cyt) genes, suggesting the divergence of the cyt gene from the chl gene. Here, we have isolated the genomic genes from the moss Pogonatum inflexum and compared their gene structures. The chl gene (sod-2) and the cyt gene (sod-3) were sequecned for 7.1 kbp and 5.6 kbp, respectively. The sod-2 contained 8 exons and 9 introns, which was the same as those of Spirogyra, although the position of the first intron was in 5'-UTR. The structure of sod-3 resembled those of higher plants. Thus, these results indicate that the divergence of the cyt gene from the chl gene occurred before the appearance of moss.
