[Location of ctDNA fragment related to CMS in Brassica napus L. var. xiangai].
The ctDNA of sterile line and its maintainer from Brassica napus L. var. xiangai were digested by restriction endonucleases EcoRI, BamHI, PstI and SmaI. Only one special fragment E3.2kb was observed in EcoRI restriction pattern of maintainer. After being eluted, this fragment was incubated with plasmid pUC9 and then transformed E. coli JM83. Through colour screening, clony hybridization and electrophoretic analyses, the special clone carrying E3.2 was obtained. The rRNA gene probe was used to hybridize with the EcoRI restriction pattern. The result showed that E3.2kb fragment is homologous to rRNA gene. And then, we use E3.2 fragment as probe to hybridize with rRNA gene digested by BamHI, EcoRI, SalII, BglII, HindIII and PstI. According to rRNA gene map, E3.2 fragment was located at the leader sequence of 16S rRNA gene, from +2.0kb to +5.4kb. Because this 3.4kb region was in the inverted repeat region of ctDNA and it is homologous to E3.2kb that related to CMS. So probably CMS is related to this 3.4kb region in the inverted repeat region of ctDNA.
Institute of Genetics, Academia Sinica, Beijing.
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W
Sun
J
J
Gao
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J
Li
F
F
Kong
D001937:Brassica / Q000235:genetics*; D002736:Chloroplasts; D002874:Chromosome Mapping; D004247:DNA / Q000235:genetics*; D012150:Polymorphism, Restriction Fragment Length; D012098:Reproduction / Q000235:genetics
D004247:DNA