用SAM法分离谷子SSR位点的研究

首次将SAM(选择扩增微卫星)法用于谷子SSR位点的分离,共获得163个含有SSR序列的克隆,其中unique SSR 106个,占所有SSR序列的65%,60个SSR序列的3′端成功设计特异引物,占unique SSR的56%。这60个SSR序列中,55个为完整型重复;5个为复合型重复,由2种不同的重复单元组成,没有发现不完整重复类型。同时讨论了SAM法在应用过程中应注意的一些关键技术环节,如接头连接、核苷酸选择策略、特异引物设计原则,及该方法存在的一些不足,如获得SSR重复次数少、一端侧翼序列缺失对扩增多态性的消极影响等。

Isolation of SSR Locus in Setaria italica by SAM Method

In the study,SAM(selectively amplified microsatellite) was used to isolate the SSR locus of Setaria italica and in all 163 clones containing SSR sequence were obtained,of which 106 were unique SSRs,accounting for 65%.In the 106 unique SSRs,60 could be used successfully to design 3′ specific primers(56%).Among the 60 SSRs,55 were complete repetition and 5 were compound ones,while no imperfect type was found.Some key technological links in SAM protocol such as adapter ligation,selective nucleotide adopt and specific primer design,and some shortcomings involved in the method such as fewer repeat unit number and the effect of lacking 5′ flank sequence on the polymorphism level,were discussed.