香菇基因组中EST-SSR的构成和分布

Compose and Distribution of EST-SSR in Genomes of Lentinula edodes

从真菌基因组计划网站(FGP)和NCBI网站数据库下载了符合条件的总长度为8.1×106bp的11150条香菇的EST(包括10条cDNA)序列,通过SSRhunter1.3软件结合手工查找,从中发现2.83%即316条EST含有一共469个SSR,平均每17.3kb出现一个EST-SSR。在所有EST-SSR中,三碱基和六碱基SSR出现最多,分别占EST-SSR总数的38.00%和20.00%。出现较多的基序为(A)n、(T)n、(GA)n、(AG)n、(TGA)n、(GAT)n和(TCTTT)n,占所有EST-SSR的35.39%。

In this study, 11,150 qualified ESTs（including 10 cDNAs）, about 8.1 × 10^6 bp in length, were downloaded from ESTs databases of Lentinula edodes in Fungal Genomies Project（FGP） and NCBI. By searching with SSRhunter 1.3 and handwork, 469 SSRs were identified in 316 ESTs, approximately 2.83 % of total ESTs. The average distance between SSRs was about 17.3kb. Trinucleotide and hexanucleotide ESR-SSRs were found to be the two most aboundent repeats, accounting for 38.00% and 20.00% of the total ESR-SSRs respectively. The most familiar motifs are （A） n, （T）n, （GA） n, （AG） n, （TGA） n, （GAT） n and（TCTIT） a, which comprised about 35.94 % of all EST-SSRs.