Evolutionary variations in the Gramineae: rearrangements of DMA fragments transferred from chloroplast genomes to mitochondrial genomes

摘要

The transfer of DNA fragments from chloroplast to mitochondrial genomes is considered a general phenomenon in higher plants (Stem and Lonsdale 1082, Stern and Palmer 1984). For rice. Nakazono and Hirai ( 1993) have determined the entire set of transferred chloroplasl sequences present in the mitochondrial genome. Total length of the transferred chloroplast sequences, whose lengths range from 32 bp to 6.8 kb, accounted for about 6% of the rice mitochondrial genome. Two of the 16 identified et-derivedfragments in rice mitochondrial genome, one comprisingrps l9-trnH-rp12-rpl23 and the other comprising PSIrp123-rbcL-atpB-alpE-trnM-trnV, were found to be separated in the chloroplast genome but were joined in the mitochondrial genome, which might be the cause for homologous recombination between rp123 and PSI123.