Different organization and altered transcription of the mitochondrial atp6 gene in the male-sterile cytoplasm of rapeseed (Brassica napus L.).
The Fo-ATPase subunit 6 gene (atp6) of rapeseed mitochondria has been isolated from both pol male-sterile and normal (fertile) cytoplasms in order to determine whether the rearrangements around the atp6 locus in pol male-sterile cytoplasm play a role in cytoplasmic male-sterility (cms). The pol cms and normal atp6 genes are identical and encode a 261-amino acid polypeptide. As a result of extensive rearrangement, a novel reading frame (pol-urf) was generated upstream of the atp6 gene only in pol cms mitochondria, which encoded 105 amino acids and might be co-transcribed with atp6. A 5'-portion of pol-urf shows sequence homology to the Oenothera ORFB gene associated with coxIII. A 5'-flanking region of the pol-urf also shows homology to that of ORF105 in Ogura cms radish mitochondria. These DNA rearrangements which give rise to pol-urf in the vicinity of the atp6 locus may be responsible for cms in rapeseed.
Handa
H
H
Department of Cell Biology, National Institute of Agrobiological Resources, Tsukuba Science City, Japan.
Nakajima
K
K
D000595:Amino Acid Sequence; D001483:Base Sequence; D015139:Blotting, Southern; D001937:Brassica / Q000201:enzymology / Q000235:genetics*; D003001:Cloning, Molecular; D003593:Cytoplasm / Q000378:metabolism; D004247:DNA; D015751:Genes, pol; D008928:Mitochondria / Q000201:enzymology*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D006180:Proton-Translocating ATPases / Q000235:genetics*; D012098:Reproduction / Q000235:genetics; D015183:Restriction Mapping; D016415:Sequence Alignment; D014158:Transcription, Genetic
D004247:DNA; D006180:Proton-Translocating ATPases