水稻白叶枯病菌基因组简单重复序列分析

Analysis of Simple Sequence Repeats in Xanthomonas oryzae pv.oryzae Genome

［目的］分析水稻白叶枯病菌基因组中的串联简单重复序列（simple sequence repeats，SSRs），为其在白叶枯病菌基因组分析和遗传多样性研究提供标记信息。［方法］利用开放的基因组数据库资源，对已完成测序的3个白叶枯病菌菌株KACC10331、MAFF311018和PXO99^A进行系统的比较分析，包括基因组中SSR的结构类型、分布、丰度等;并以实例解读了在应用中可能遇到的问题。［结果］在这3个白叶枯病菌菌株的基因组中，由1～6个核苷酸为基序的SSR序列分别有940、926和1 035个;平均每隔5.26、5.34和5.06 kb的距离就有1个大于15 bp的SSR序列。在1～6个核苷酸为基序的SSR序列中，数量最多的是6碱基重复，其次分别是3、5、4、2碱基重复序列，而单碱基重复数目极少。在这3个菌株的基因组中，种类丰富、变异性高的是4、5、6个核苷酸的重复基序，但等位序列上3种菌株间的基序可能不同。［结论］3种白叶枯病菌菌株的SSR在结构类型和分布规律上均具有一定的相似性。

[ Objective ] The research aimed to analyze simple sequence repeats in Xanthomonas oryzae pv. oryzae genome and provide mark information of the research in analysis of simple sequence repeats in Xanthomonas oryzae pv. oryzae genome and genetic diversity. [ Method ] In this study,we analyzed and compared the type,relative distribution and relative density of SSRs in the three Xoo races sequenced,KACC10331, MAFF311018 and PXO99^A respectively. And we made an application of the possible problems by examples. [ Result ] In the three genomes,the SSRs numbers are 940,926 and 1 035 ,respectively. The sequence of above 15bp SSRs is 5. ＂）6 kb,5.34 kb and 5.06 kb or so distance ,respectively. Hexa-nucleotide repeats are the most abundant,but mono-nueleotide repeats are rare. Tetra-,penta- and hexa-nueleotide repeats are more abundant and variant,indicating higher mutation rates in these species. [ Conclusion] The SSRs type and distribution are similar among the three species.