穗花杉的转录组测序及其转录组特性分析

Transcriptome Sequencing and Analysis of Amentotaxus argotaenia (Hance) Pilger

[目的]通过对红豆杉科穗花杉属的穗花杉进行转录组测序,为穗花杉的萜类合成途径和分类学研究提供支持。[方法]利用Hi Seq2500技术对穗花杉的茎叶进行转录组测序。[结果]穗花杉转录组测序共得到8.14 Gb的clean data。从头组装共获得82 884条unigene,其中有27 495条unigene被注释。此外,在82 884条unigene中共搜索到2 827个SSR位点,单核苷酸重复SSR出现频率最高(60.1%),其次为三核苷酸重复SSR(25.4%)。在穗花杉unigene中挖掘出了1个牦牛儿基焦磷酸合成酶(GPS)、1个法尼烯基焦磷酸合成酶(FPS)和5个牦牛儿基牦牛儿基焦磷酸合成酶(GGPS)的同源基因,同时得到紫杉二烯合成酶(TS)同源基因13个。[结论]发现了20个与萜类合成有关的unigene和2 827个SSR位点,为今后穗花杉萜类生物合成研究,特别是紫杉二烯合成酶编码基因的研究打下了基础,也为该物种系统分类地位及遗传多样性研究提供了新的遗传信息。

[ Objective ] The transcriptome of Amentotaxus argotaenia （ Hance ） Pilger of Amentotaxus in Taxaceae was sequenced and analyzed for its terpenoid biosynthetic pathway and taxonomy research. [ Method ] The tran- scriptome of the mixture of stem and leave ofA. argotaenia was sequenced by using HiSeq2500. [ Result]8.14 Gb clean data was obtained from the transcriptome of A. argotaenia. 82 884 unigene were obtained and 27 495 unigene were annotated using the six public databases. Besides, 2 827 SSRs were identified from the 82 884 unigene. The most abundant type of repeat motif was mono-nucleotides （60.1%）, followed by tri-nueleotides （25.4%）. Among the unigenes of A. argotaenia, one homologous gene of geranyl diphosphate synthase （GPS） , one homologous gene of famesyl diphosphate synthase （FPS） and five homologous genes of geranylgeranyl diphosphate synthase （GGPS） were identified. In addition, 13 homologous genes to taxadiene synthase gene （TS） in Taxus were obtained using TBLASTN. [ Conclusion] In this study, 20 unigenes relating to terpenoid biosynthesis and 2 827 SSRs were identi- fied in A. argotaenia. Our work will facilitate the study about the terpenoid biosynthetic genes especially taxadiene synthase gene in A. argotaenia and may provide some foundational genetic data to study its taxonomy and diversity.