香菇EST-SSR标记的开发及应用

Development of Expressed Sequence Tag-Simple Sequence Repeat(EST-SSR)Markers in Lentinula edodes

从NCBI中下载了12 184条香菇（Lentinula edodes）表达序列标签（expressed sequence tag,EST）序列,处理后得到全长3 681 177 bp的4 684个Unigene。在其中共发掘出142个简单重复序列（simple sequencerepeat,SSR）,分布于120条EST中,分布频率为2.99%（平均分布距离：25.924 kb）。其中,单、二、三核苷酸重复是主要的重复类型,A/T,AG/CT,ACG/CTG是单、二、三核苷酸的主要重复基序,分别占所有EST-SSR的23.23%、21.83%和10.56%。利用引物设计软件PrimerPremier5.0设计了40对引物,并利用6%变性聚丙烯酰胺凝胶在18个香菇品种中进行检测。其中,22对引物为多态性引物,多态率为55%。应用NTSYS软件的聚类方法分析表明,18份材料遗传相似系数范围为0.375-0.984,与前人研究结果相符。

A total of 12 184 Lentinula edodes expressed sequence tags（ESTs） were downloaded from NCBI and shown to be associated with 4 684 Unigenes comprising 3 681 177 bp in length.A MISA search revealed a total of 142 simple sequence repeats（SSRs） with a frequency of 2.99% and an average distance distribution of 25.9 kb.The most abundant mononucleotide,dinuclotide and trinucleotide repeats were A/T,AG/CT and ACG/CTG,accounting for 23.23%,21.83% and 10.56% of each type,respectively.Forty EST-SSR primer pairs were designed by PrimerPremier 5.0,22 of which revealed polymorphic bands in the DNA of 18 L.edodes strains.NTSYS-computed similarity coefficients for the 18 strains ranged between 0.375~0.984,which was approximately in accordance with their diversity based on previous research.