地黄环烯醚萜合成后修饰相关基因的挖掘与分析

Analysis of Genes Involved in the Synthesis and Modification of Iridoids of Rehmannia glutinosa

本研究采用Illumina Hi Seq 2500技术对地黄脱毒苗进行转录组测序,获得了地黄转录组信息,并对构建好的地黄基因Unigene库进行蛋白功能注释、KEGG代谢通路分析等生物信息学分析,以期大规模挖掘与地黄环烯醚萜类成分生物合成及后修饰相关的基因。应用高通量测序技术对地黄组培苗进行转录组测序,得到13.61Gb的干净数据,De novo组装后共获得70778条Unigene,其中33.428(47.23%)条unigenes能被Nr、Swiss-Prot、Pfam、KOG、KEGG、GO和COG等公共数据库注释。进一步对被注释的地黄萜类生物合成及后修饰相关基因进行挖掘发现,地黄转录组中共有81个Unigene参与萜类骨架合成;共有226个Unigene可能参与CYP450介导的环烯醚萜骨架的氧化修饰;共有102个Unigene与糖基转移酶相关。地黄转录组数据库的获得为探索地黄环烯醚萜类成分的生物合成研究奠定了基础,为后续基因功能的分析等研究提供分子水平依据。

The Illumina HiSeq 2500 sequencing （RNA-Seq） method was used to analyze the transcriptome of Rehmannia glutinosa virus-free seedlings in this paper. The transcriptome information was obtained, and protein functional annotation, Kyoto encyclopedia of genes and genomes （KEGG） metabolic pathway analysis, and other bioinformatics analyses were conducted on the constructed R. glutinosa Unigene database, in order to deeply explore the genes related to biosynthesis and modification of iridoids in R. glutinosa. High-throughput sequencing technology was used for transcriptome sequencing analysis in R. glutinosa seedlings, generating 13.61 GB of clean data, and 70,778 unigenes were obtained after de novo assembly. Among them, 33,428 unigenes （47.23%） could be annotated in public non-redundant （Nr） databases, including the Swiss protein database （Swiss-Prot）, protein families （Pfam）, eukaryotic orthologous groups （KOG）, KEGG, gene ontology （GO）, and cluster of orthologous groups （COG）. The transcripts encoding known enzymes involved in biosynthesis and post modification ofterpenoids were discovered in the Illumina dataset, and 81 unigenes involved in terpenoid backbone biosynthesis were identified. Additionally, 226 unigenes might be involved in the cytochrome P450 （CYP450）-mediated oxidative modification of iridoid backbones, and 102 unigenes were associated with uridine diphosphate （UDP）-glycosyltransferases （UGTs）. The transcriptome data from this study lays a basis for the study of the biosynthesis ofiridoids and provides a reference for the follow-up analysis of gene functions and other studies.