曼氏血吸虫EST中的微卫星分析  

Analysis of microsatellites from Schistosoma mansoni ESTs

作　　者：唐远菊[1] 罗洪林[1] 聂奎[1] 

机构地区：[1]西南大学动物科技学院,重庆400716

出　　处：《中国预防兽医学报》2007年第8期629-633,共5页Chinese Journal of Preventive Veterinary Medicine

摘　　要：美国基因组研究协会网上公布了138 259条曼氏血吸虫EST(表达序列标签)序列,总长约为52345kb。通过分析发现,其中包含了8 133条SSR(简单重复序列),检出率为5.88%,平均每6.4 kb含有一个SSR。三核苷酸重复基元的SSR最多,占总数的54.2%,其次为二核苷酸和四核苷酸,分别占20.5%和20.6%,五核苷酸最少,只占4.7%。在曼氏血吸虫EST中没有发现单核苷酸重复基元和六核苷酸重复基元的SSR。同时,在各种SSRs重复单元中,富含A碱基的重复单元占据优势地位,如:AT、AG、AC、AAT、AAG、AAC、AAAT、AAAC、AAAAT和AAAAG重复基序,而富含GC碱基的重复单元在基因编码区中含量较低。本文通过分析SSR在曼氏血吸虫EST中的分布频率与密度,为曼氏血吸虫和近缘种属寄生虫SSR标记的开发提供信息,有利于进一步开展吸虫的系统发育以及比较基因组学的研究。A total of 8133 SSR （Simple sequence repeat） were identified from 138259 ESTs （Expressed sequence tag） consisting of 52345 kb in the TIGR Schistosoma mansoni Gene Index. In average, one SSR was identified in every 6.4 kb EST sequenses. Trinucleotide repeats （54.2 %） motifs appeared to be the most abundant type in the Schistosoma mansoni, followed by tetranucleotide （20.6 %） and dinecleotide （20.5 %） and pentanucleotide repeats （4.7 %）. No mononucleotide and hexanucleotide repeats were found. SSR with A-rich repeats were predominant, such as AT, AG, AC, AAT, AAG, AAC, AAAT, AAAC, AAAAT and AAAAG repeats, whereas GC-rich repeats were rare in the coding regions.

关 键 词：曼氏血吸虫 表达序列标签 微卫星 简单重复序列 

分 类 号：Q781[生物学—分子生物学] S852.7[农业科学—基础兽医学]