基于转录组测序挖掘商陆皂苷甲生物合成相关基因

Transcriptome analysis reveals candidate genes involved in esculentoside A biosynthesis in Phytolacca americana

为研究商陆皂苷甲的生物合成途径,利用Illumina Hi Seq 4000高通量测序技术对商陆幼苗进行转录组测序,得到9.60 Gb clean data,经Trinity软件组装后获得63 957条unigenes,平均长度988.82 bp,其中24 517条unigenes(38.33%)能被Nr、Swiss-Prot、COG、KOG、Pfam、GO、KEGG等公共数据库注释。对注释得到的unigenes进行KEGG代谢通路分析,发现商陆转录组中有53个unigenes参与萜类骨架合成通路,有8个unigenes参与三萜合成通路,还有417个unigenes参与商陆其他次生代谢途径。进一步分析参与商陆皂苷甲生物合成后修饰酶相关基因,发现有130个unigenes可能具有CYP450的功能,参与商陆次生代谢产物的氧化/羟基化修饰;有46个unigenes与糖基转移酶UGT相关。商陆转录组数据的获得为研究商陆皂苷甲和其他次生代谢产物的生物合成途径奠定了基础,也为商陆药材品质的形成提供理论依据。

In order to study the biosynthesis pathway of esculentoside A, the Illumina Hi Seq 4000 high-throughput sequencing method was used to analyze the transcriptome of Phytolacca americana seedlings. The 9.60 Gb clean data were obtained after the transcriptome of P. americana assembled by Trinity software. The total 63 957 unigenes were obtained after assembly and the average length was 988.82 bp, among them 24 517 unigenes（38.33%） were annotated in the public databases Nr, Swiss-Prot, COG, KOG, Pfam, GO and KEGG. According to the assignment of KEGG pathway, 53 unigenes were involved in terpenoid backbone biosynthesis and 8 unigenes involved in triterpenoid biosynthesis. Additionally, there were 417 unigenes assigned to other secondary metabolic pathways in P. americana. The post-modification enzyme genes involved in the esculentoside A biosynthesis were also analyzed in the transcriptome of P. americana. The results indicated that 130 unigenes may have the function of CYP450 which was involved in oxidation/hydroxylation modification of P. americana secondary metabolites. Furthermore, 46 unigenes had the function of glycosyltransferase UGT. The transcriptome data of P. americana laid a foundation for studying the biosynthesis pathway of esculentoside A and other secondary metabolites, and also provided theoretical basis for formation of medicinal materials quality.