基于454 ESTs的麻黄转录组研究

Transcriptome characterization of Ephedra sinica with 454 ESTs

该研究应用454 GS FLX Titanium高通量测序技术对5年生草麻黄Ephedra sinica的草质茎进行转录组测序,共获得48 389条表达序列标签(express sequence tags,ESTs),序列平均长度为373 bp。所得序列与Gen Bank中麻黄的EST合并拼接,获得18 801条一致性序列(unigene)。通过与公共数据库中的序列进行同源性比较分析对所得转录本进行功能注释,结果表明其中56.0%(10 531条)的unigenes与其他生物的已知基因具有一定程度的同源性。进一步分析获得了19条可能参与麻黄生物碱生物合成的序列(共编码9个关键酶),97条细胞色素P450序列,以及大量转录因子序列。该研究为麻黄生物碱类化合物的生物合成研究奠定了基础,同时为麻黄转录组学的研究提供了海量数据,对于麻黄的功能基因组学研究具有重要意义。

Using the latest 454 GS FLX platform and Titanium regent, a substantial expressed sequence tag （ESTs） dataset of Ephedra sinica was produced, and the profile of gene expression and function gene of which were investigated. A total of 48 389 reads with an average length of 373 bp were generated. These 454 reads were assembled into 18 801 unigenes, which were all 454 sequencing identified. A total number of 10 531 unigenes（56.0% ） were annotated using BLAST searches （E-value≤ 1 × 10-5） against the Nr, Nt, TAIR, SwissProt and KEGG databases. With respect to genes related to ephedrine biosynthesis, 19 unigenes（ encoding 9 enzymes） were found. A total of 97 putative genes encoding cytochrome P450s were also discovered. Data presented in this study will provide an important resource for the scientific community that is interested in the functional genomics and secondary metabolism of E. sinica.