利用GISH和C_0t-1DNA-FISH对稻属B,C,G基因组的比较分析  

Comparative Analysis of B,C,G Genome in Oryza with C_0t-1 DNA-FISH and GISH

作　　者：覃瑞[1] 马骞[1] 王德彬[1] 吴绮[1] 

机构地区：[1]中南民族大学生命科学学院,武汉430074

出　　处：《中南民族大学学报（自然科学版）》2009年第2期31-35,共5页Journal of South-Central University for Nationalities：Natural Science Edition

基　　金：教育部留学回国人员启动基金资助项目(BZY04003);湖北省自然科学基金资助项目(2006ABA367)

摘　　要：为探究稻属B,C,G基因组之间的关系以及研究中高度重复序列在稻属不同物种基因组进化中的作用,利用药用野生稻和斑点野生稻的中度和高度重序列C0t-1 DNA和总基因组作为探针,对疣粒野生稻进行了比较染色体原位杂交分析.该2种野生稻的总基因组和C0t-1 DNA在疣粒野生稻染色体上信号覆盖率分别为(72.39±0.11)%,(75.60±0.18)%,(47.93±0.16)%,(55.47±0.12)%.此外,以C0t-1 DNA的杂交信号组成为依据,对疣粒野生稻染色体组进行了核型分析.结果表明:G基因组和B,C基因组之间的关系都比较远,其原因可能是G基因组要早于B,C基因组从稻属的祖先中发生分化,并在进化过程中发生加倍、重排和基因选择性丢失等现象,形成了各自种的特异基因组成分.稻属基因组中度和高度重复序列与功能基因一样,在不同种中也存在着相当的同源性和保守性,并在进化过程中得以保存下来.药用野生稻和疣粒野生稻基因组增大的重要原因之一,可能是基因组中度和高度重复序列加倍的结果.Fluorescence in situ hybridization analyses were applied to somatic chromosomes preparations of O. meyeriana Baill using C0t-1 DNA and genomic DNA from O. officinalis and O. punctata as probes to investigate the relationship of 13, C, G genomes in oryza sativa and study the function of the repetitive sequences in the evolution process of different species of oryza sativa. The coverage rate of hybrid signal of C0t-1 DNA and genomic DNA from these two wild rice on the chromosomes preparations of O. meyeriana Baill were （72.39±0. 11）%, （75.60±0. 18）%, （47.93± 0.16）%, （55.47±0.12） % respectively. Furthermore, we characterized the karotype of O. meyeriana Baill through the comparison of its chromosomes hybridized with C0t-1 DNA from the two wild rice species. The results indicated that the G genome was far from the B and C genomes. The reason may be that the G genome was separated from the ancestor of oryza sativa before the B, C genome and to the duplication or rearrangement of the sequences and loss of gene selectively during their evolution process, which made O. meyeriana Baill a special species of oryza sativa. The moderately and highly repetitive sequences in a genome of oryza sativa were similar to the function gene sequences in that they were also homologous and conservative among different genomes being preserved in the evolution-process. The duplication of the moderately and highly repetitive sequences in a genome may be a reason for the enlarged genomes of O. meyeriana Baill and O. officinalis.

关 键 词：重复序列 核型 信号覆盖率 疣粒野生稻 

分 类 号：Q943[生物学—植物学]