中国板栗EST-SSR信息分析及其通用性

Characteristic and Generality of EST-SSRs of Castanea mollissima

摘要:

从已公布的壳斗科(Fagaceae)基因组数据库中获得48501条中国板栗(Castanea mollissima)EST序列，其中8479条EST含有 12116个长度大于10 bp的SSR，EST-SSR的出现频率为24.98%。二核苷酸重复和三核苷酸重复是中国板栗EST-SSR最主要的重复类型，分别占总数的38.05%和42.20%。对中国板栗EST-SSR标记在茅栗(C. seguinii)和锥栗(C. henryi)上的通用性检测表明，677对中国板栗EST-SSR引物皆能扩增，证实这些引物在栗属中国特有种间具有很高的通用性。115个位点的多态性分析表明，中国板栗、茅栗和锥栗分别有106、108和101个位点表现出多态性。在575个等位基因中，有260个(45.22%)是3物种的共有等位基因，各物种都有各自特有的等位基因。这项研究为中国栗属植物EST-SSR标记的建立及应用奠定了基础。

Abstract:

A total of 48501 expressed sequence tags (ESTs) of Castanea mollissima were obtained from database of Fagaceae Genomics, of which 8479 ESTs contain 12116 simple sequence repeats (SSRs) with motifs longer than 10 bp, with the frequency of SSRs up to 24.98%. Dinucleotide and trinucleotide repeats are the main EST-SSR types in Chinese chestnut, accounting for 38.05% and 42.20% of all EST-SSRs, respectively. The Chinese chestnut EST-SSR markers showed 100% transferability across the two endemic species to China, C. henryi and C. seguinii. There were 106, 108 and 101 polymorphic loci from 115 loci in C. mollissima, C. seguinii and C. henryi, respectively. While 260 out of the 575 alleles (45.22%) were shared among the three species, unique alleles in each species were also detected. These informative EST-SSR markers can be used in population genetic studies and comparative mapping of Chinese chestnuts.