基于牡丹EST信息的滇牡丹SSR标记开发

对NCBI(美国国立生物技术信息中心)中牡丹的ESTs(expressed sequence tags)的序列进行分析,结果表明:在所分析的2 204条序列中,仅324条分布有SSRs(simple sequence repeats),占全部ESTs序列的14.70%;SSR的出现频率为15.20%,共计335个,其中,二核苷酸重复比例84.18%,三核苷酸重复比例为15.22%,四和六核苷酸重复比例为0.30%。在此基础上,利用软件(serafer 1.3)设计了51对备选SSR引物,以6个滇牡丹不同花色类群DNA为模板对引物进行筛选,其中,10对引物有扩增产物;用这些引物进一步在10个类群50个DNA模板进行多态性测试,结果显示:上述10对SSR引物均有多态性,且同一类群内不同模板DNA间也存在多态性。本研究结果证明:基于牡丹EST信息建立SSR标记是一种有效而可行的方法,有助于滇牡丹遗传多样性分析及基因组学方面的研究。

SSRs Marking of Paeonia delavayi Based on Peony EST Data

Through sequences analysis of Paeonia suffruticosa ESTs (expressed sequence tags) deposited in NCBI, only 335 SSRs (simple sequence repeats) were found. These SSRs are distributed in 324 ESTs out of the 2 204 ESTs examined, accounting for 14.70% of the total. The frequency of SSR was 15.20%, in which, the repetitive proportions of dinucleotide, trinucleotide, tetranucleotide and hexanucleotide were 84.14%, 15.22%, 0.30% and 0.30%, respectively. 51 candidate SSR primers were designed according to the ESTs sequences that containing SSRs, by using serafer 1.3 software. The 51 candidate SSR primers were screened against genomic DNA of 6 different flower color groups in P. delavayi, of which, 10 primer pairs amplified visible bands with polymorphism among 50 genomic DNAs from 10 color groups in P. delavayi. The results proved that the development of EST-SSR markers based on ESTs in P. suffruticosa is an effective and feasible approach, which will conduce to study on genetic diversity and genomics in P. delavayi.