扁玉螺转录组SSR信息分析

Analysis of SSR Information in the Transcriptional Group of Neverita didyma

采用生物信息学方法分析扁玉螺转录组文库EST序列(SSR)位点,并且设计简单重复序列(SSR)引物,以期为扁玉螺分子标记辅助育种提供有力的工具。对扁玉螺进行转录组测序采用Illumina Hiseq^(TM)高通量测序平台,再利用Micro SAtellite(MISA)工具,分析扁玉螺转录组中SSR的重复基元及其分布频率。利用Primer 3软件设计引物,并且通过SSRFinder筛选出SSR引物。从233 853条Unigenes中找到202 337个符合条件的SSRs,发生频率为45.34%,SSR位点的出现频率为86.53%。SSR位点中单核苷酸重复是主要类型,占总SSRs的63.44%,其次为双核苷酸和三核苷酸,分别为24.12%和6.73%。SSR所包含的重复基元中,单核苷酸重复基元A/T最多,占总SSR的54.15%;其次为双核苷酸AC/GT多,为15.9%。扁玉螺转录组中SSR位点出现频率高,而且类型丰富;大量的SSR分子标记技术有助于扁玉螺分子育种与遗传多样性分析提供更多的依据。

Bioinformatics method was used to analyze the EST sequence （SSR） locus of Neverita didymatranscriptome library. A simple repeat sequence （SSR） primer was designed to provide a powerful tool formolecular marker assisted breeding of N. didyma. The Illumina HiseqTM high throughput sequencing platformwas used to transcribe group sequencing, and then Micro SAtellite （MISA） was used to analyze the duplicationprimitives and their distribution frequencies of SSR in the transcriptome of the N. didyma. Primers were de-signed by Primer 3 software and SSR primers were screened by SSRFinder. A total of 233 858 SSRs werefound in the transcriptome of N. didyma, distributed in 202 337 unigenes with distribution frequency of45.34%. Mono-nucleotide repeat was the main type, accounted for as much as 63.44% of all SSRs, followed byDi-nucleotide repeat motif （24.12%） and Tri-nucleotide repeat motif （6.73%）. The mono-nucleotide repeatmotifs of A/T was the predominant repeat types （54.15%）, followed by di-nucleotide repeat motifs of AC/GT（15.9%）. In the transcriptome of N. didyma, the frequency of SSR loci is high, and the type is abundant.Alarge number of SSR markers can provide more evidence for molecular breeding and genetic diversity analysis.