Fluorescence in situ hybridization （FISH） and comparative genomic hybridization （CGH） were applied to somatic chromosomes preparations of Oryza sativa, O. officinalis, and O. meyeriana with labeled probes of Cot-1...Fluorescence in situ hybridization （FISH） and comparative genomic hybridization （CGH） were applied to somatic chromosomes preparations of Oryza sativa, O. officinalis, and O. meyeriana with labeled probes of Cot-1 DNA and genomic DNA＇from the cultivated rice. The coverage percentage （%） and size （Mb） of Cot-1 DNA in O. sativa, O. officinalis, and O. meyeriana were 47.1 ±0.16, 38.61 ±0.13, 44.38＋_0.13, and 212.33 ± 1.21,269.42 ± 0.89, 532.56± 1.68 Mb, respectively. The coverage percentage and size of genomic DNA from O. sativa in O. officinalis and O. meyeriana were 91.0, 93.6% and 634, 1 123 Mb, respectively, in which 365 and 591 Mb in O. officinalis and O. meyeriana were from O. sativa genomic DNA, but not from repetitive sequences of O. sativa, and the uncoverage genome size in O. officinalis and O. meyeriana were 64 and 78 Mb, respectively. In addition, karyotype analysis was conducted based on the signal bands of Cot-1 DNA in O. sativa, O. officinalis, and O. meyeriana. The results showed that highly and moderately repetitive sequences in Oryza genus were conserved as the functional genes during evolution. The repetitive sequences reduplication may be one of the important causes of the genome enlargement of O. officinalis and O. meyeriana, and O. officinalis genome enlarged more slowly when compared with O. meyeriana. Based on the above results, it is concluded that O. officinalis and O. meyeriana were formed by reduplication, rearrangement, and gene selective loss during the evolution process.展开更多
To explore an effective and reliable karyotyping method in Brassica crop plants,Cot-1 DNA was isolated from Brassica oleracea genome,labeled as probe with Biotin-Nick Translation Mix kit,in situ hybridized to mitotic ...To explore an effective and reliable karyotyping method in Brassica crop plants,Cot-1 DNA was isolated from Brassica oleracea genome,labeled as probe with Biotin-Nick Translation Mix kit,in situ hybridized to mitotic spreads,and where specific fluorescent bands showed on each chromosome pair.25S and 5S rDNA were labeled as probes with DIG-Nick Translation Mix kit and Biotin-Nick Translation Mix kit,respectively,in situ hybridized to mitotic preparations,where 25S rDNA could be detected on two chromosome pairs and 5S rDNA on only one.Cot-1 DNA contains rDNA and chromosome sites identity between Cot-1 DNA and 25S rDNA was determined by dual-colour fluores-cence in situ hybridization.All these showed that the karyo-typing technique based on a combination of rDNA and Cot-1 DNA chromosome landmarks is superior to all but one.A more exact karyotype of B.oleracea has been analyzed based on a combination of rDNA sites,Cot-1 DNA fluorescent bands,chromosome lengths and arm ratios.展开更多
基金This work was supported by the National High Tech R ＆ D Program of China （863 Program, 2004AA227120） the Scientific Research Foundation for the Returned 0verseas Chinese Scholars, Ministry of Education of China （BZY04003）+1 种基金 China Postdoctoral Science Foundation （20040350574）the Project of Science and Technology for Youth, Wuhan, China （2004500607135）.
文摘Fluorescence in situ hybridization （FISH） and comparative genomic hybridization （CGH） were applied to somatic chromosomes preparations of Oryza sativa, O. officinalis, and O. meyeriana with labeled probes of Cot-1 DNA and genomic DNA＇from the cultivated rice. The coverage percentage （%） and size （Mb） of Cot-1 DNA in O. sativa, O. officinalis, and O. meyeriana were 47.1 ±0.16, 38.61 ±0.13, 44.38＋_0.13, and 212.33 ± 1.21,269.42 ± 0.89, 532.56± 1.68 Mb, respectively. The coverage percentage and size of genomic DNA from O. sativa in O. officinalis and O. meyeriana were 91.0, 93.6% and 634, 1 123 Mb, respectively, in which 365 and 591 Mb in O. officinalis and O. meyeriana were from O. sativa genomic DNA, but not from repetitive sequences of O. sativa, and the uncoverage genome size in O. officinalis and O. meyeriana were 64 and 78 Mb, respectively. In addition, karyotype analysis was conducted based on the signal bands of Cot-1 DNA in O. sativa, O. officinalis, and O. meyeriana. The results showed that highly and moderately repetitive sequences in Oryza genus were conserved as the functional genes during evolution. The repetitive sequences reduplication may be one of the important causes of the genome enlargement of O. officinalis and O. meyeriana, and O. officinalis genome enlarged more slowly when compared with O. meyeriana. Based on the above results, it is concluded that O. officinalis and O. meyeriana were formed by reduplication, rearrangement, and gene selective loss during the evolution process.
基金This work was supported by the President Foundation of the Institute of Oil Crops,Chinese Academy of Agricultural Sciences(No.200301)the Topping Youth Foundation of Hubei Province(No.2005ABB028)the Chenguang Program of Wuhan City(No.20045006071-37).
文摘To explore an effective and reliable karyotyping method in Brassica crop plants,Cot-1 DNA was isolated from Brassica oleracea genome,labeled as probe with Biotin-Nick Translation Mix kit,in situ hybridized to mitotic spreads,and where specific fluorescent bands showed on each chromosome pair.25S and 5S rDNA were labeled as probes with DIG-Nick Translation Mix kit and Biotin-Nick Translation Mix kit,respectively,in situ hybridized to mitotic preparations,where 25S rDNA could be detected on two chromosome pairs and 5S rDNA on only one.Cot-1 DNA contains rDNA and chromosome sites identity between Cot-1 DNA and 25S rDNA was determined by dual-colour fluores-cence in situ hybridization.All these showed that the karyo-typing technique based on a combination of rDNA and Cot-1 DNA chromosome landmarks is superior to all but one.A more exact karyotype of B.oleracea has been analyzed based on a combination of rDNA sites,Cot-1 DNA fluorescent bands,chromosome lengths and arm ratios.
