华仁杏幼果转录组SSR信息分析及其分子标记开发

De Novo Transcriptomic Analysis and Development of EST-SSRs for Huaren Apricot

为了解华仁杏微卫星(SSR)分布规律,开发EST-SSR引物,为华仁杏种质资源评价与辅助育种提供有效的鉴定标记。本研究采用生物信息学方法对华仁杏幼果转录组SSR位点的数量、频率、分布特征进行了统计分析;利用转录组数据进行了SSR引物的筛选和开发,并利用开发出的引物对华仁杏29个无性系进行了多态位点检测和鉴定。结果表明:华仁杏幼果EST-SSR的分布频率为19.21%,重复单元的重复次数分布在5~24次之间,优势重复基序为单核苷酸、2核苷酸、3核苷酸,分别占总SSR的19.81%、46.47%、32.49%。参试的139对引物中有39对引物可扩增出目标序列,其中24对引物可检测出多态性位点,占参试引物总数的17.27%。24对引物在29个华仁杏无性系中共检测出了170个等位基因位点,多态性信息含量(PIC)介于0.33~0.87之间,平均为0.64,其中高多态性引物19条,占多态性引物比例的79.2%。本研究对华仁杏转录组SSR信息进行了分析,并开发出了19对高多态性SSR引物,5对中多态性引物,为华仁杏种质资源评价及分子标记辅助育种提供了基础。

The objective of this study was to unlock the microsatellites（ SSR） for developing EST-SSR primers,which might be useful in evaluation of apricot germplasm resource and marker-assisted breeding. In this study,by bioinformatics analysis,we explore the number,frequency and distribution of SSR loci in the transcriptome dataset of young apricot fruit. The developed SSR primer sets were tested using 29 clones of Huaren apricot. The results showed that the frequency of EST-SSR was 19. 21% and the repetitive number of repeat units was between 5 and 24 times. The predominant repeat motifs included single nucleotide,dinucleotide and trinucleoside,with a proportion of19. 81%,46. 47%,32. 49%,respectively. By synthesizing and testing 139 pairs of primers,39 pairs of primers could produce PCR fragments. Twenty-four of primer combinations were polymeric and amplified 170 alleles among29 clones of Huaren apricot. Within this test population,the PIC ranged from 0. 33 to 0. 87 with an average of 0. 64.Thus,this work by analyzing transcriptome datasets revealed 19 pairs of SSR primers with high polymorphism and five with moderate polymorphism. These newly-generated SSR primers might be useful resource in evaluation of the Huaren apricot germplasm resource and marker-assisted breeding.