黑白轮枝菌基因组中微卫星的频率和分布  

Frequency and Distribution of Microsatellites in the Whole Genome of Verticillium albo-atrum

作　　者：李志芳[1] 冯自力[1] 赵丽红[1] 师勇强[1] 李彩红[1] 王玲飞[1] 刘义杰[1] 朱荷琴[1] 

机构地区：[1]棉花生物学国家重点实验室/中国农业科学院棉花研究所,河南安阳455000

出　　处：《棉花学报》2013年第2期135-141,共7页Cotton Science

基　　金：中央级公益性科研院所基本科研业务费专项2013年度所长基金项目(SJB1304);国家自然科学基金(31201466)

摘　　要：为了明确重要植物病原真菌黑白轮枝菌基因组中的微卫星(SSR)分布情况,利用软件SciRoKo从已测序的VaMs102菌株基因组(32.8 Mb)中,成功搜索得到4224个SSR。结果显示,三碱基重复微卫星的数量最多,为1481个,占SSR总数的35.1%;其次是二碱基、六碱基、四碱基和五碱基;单碱基重复的微卫星数量最少,为308个,仅占总数的7.3%。不同重复单元的微卫星在黑白轮枝菌基因组中的分布是非随机的,具有明显的偏好性。单碱基、二碱基、四碱基和五碱基偏爱出现于非编码区,尤其是基因间区。三碱基和六碱基重复微卫星较为集中分布在外显子区,并且重复次数变化丰富,推断黑白轮枝菌编码区的SSR可能会通过调节自身的重复次数来适应新环境。To identify the distribution of simple sequence repeats （SSRs） in primary plant pathogen Verticillium albo-atrum genome, this study successfully scanned 4224 SSR in the 32.8 Mb genome of sequenced VaMsl02 isolate. Results showed that the tri-nucleotide repeats （tri-nt） was the most abundant microsatellite type. The number of tri-nt SSRs was 1481 comprising 35.1% of the total number of SSRs, followed by di-nt, hexa-nt, tetra-nt and pentra-nt SSRs in that order. Mono-nt SSR had the smallest population, only 308, comprising 7.3% of the total number. Furthermore, the SSRs in different repeat units exhibited a differential or non-random distribution in different genomic locations. Mono-nt, di-nt, tetra-nt and penta-nt SSRs preferred to present in the noncoding regions, especially intergenic. Tri-nt and hexa-nt SSRs concentrated distributed in the exonic regions, and the number of triplet-motif repeats is variable across the V. albo-aaum genome, perhaps indicating that it may help promote adaptation to new environment through modulating the repeat times.

关 键 词：黑白轮枝菌 基因组 简单重复序列 非随机分布 

分 类 号：S562[农业科学—作物学]