COMPLETE SEQUENCE OF WHEAT CHLOROPLAST DNA

The complete nucleotide sequence of the chloroplast (cp) DNA of common wheat (Triticum aestivum cv. Chinese Spring) has been determined. The circular double stranded DNA consisting of 134,523 bp harbors a pair of inverted repeat regions (IRA and IRB) with 20695 bp, which disrupts the other region into a small and a large single copy region (SSC and LSC) of 12790 bp and 80343 bp, respectivley. The borders of IR and LSC are located on the intervenic region between psbA and rps19, rp122 and rps19. While, the borders of IR and SSC are determined inside of ndhH gene, and the intervening region between ndhF and a counter part of ndhH. These border positions are similar to those of rice cpDNA, differing from those of maize cpDNA. The overall basic structure and gene content of wheat cpDNA were similar to its relatives, rice and maize. In the IRs, 23S, 16S, 4.5S and 5S ribosomal RNA genes were involved. 30 tRNA genes were dispersed in the plastome. 70 genes encoding functional proteins in rice and maize cpDNAs were also found in wheat cpDNA. Structural alterations of wheat cpDNA in comparison to the arrangement of rice and maize cpDNAs were detected.