目的 挖掘与款冬萜类化合物生物合成途径相关的关键酶基因。方法 利用Illumina HiSeq2500测序平台对野生款冬花蕾和叶进行转录组测序，使用Trinity软件de novo从头组装，并通过基因功能注释、差异表达基因分析等生物信息学方法进行分析，挖掘款冬中萜类化合物生物合成途径相关的酶基因。结果 转录组测序获得39 912 371条高质量reads（SRA号：SRR9113366，SRR9113367），组装获得91 118条Unigene，55 830条Unigene在NR、Swiss-Prot、GO、COG、KEGG等数据库得到注释。鉴定出参与款冬萜类化合物生物合成相关酶基因的129个Unigene，包括91个参与三萜骨架生物合成酶基因，32个萜类合成酶基因，6个细胞色素P450基因，其中差异表达基因25个，涉及上游MVA途径的4个差异基因在花蕾中表达量高于叶，MEP途径的5个差异基因在叶中表达高于花蕾，另外还有10个基因在叶中高表达，9个基因在花蕾中高表达。根据差异基因HMGR、TPS、AS、CYP450基因在花蕾中高表达，推测可能与花蕾中萜类物质含量高有关。结论 从款冬转录组数据库中初步获得了可能参与萜类化合物生物合成途径的候选关键酶基因，为进一步阐明款冬萜类化合物生物合成的分子机制奠定基础。

Objective To screen candidate genes involved in the terpenoid biosynthetic pathway of Tussilago farfara. Methods The transcriptome of buds and leaves of wild T. farfara were respectively sequenced using the Illumina HiSeq 2500 high-throughput sequencing platform. The clean reads were de novo assembled by Trinity software, and the assembled sequences then followed by a series of bioinformatics analysis such as gene function annotation and differential expression gene. According to sequence annotation and differentially expressed genes analysis, the key enzyme genes related to the terpenoid biosynthesis were identified. Results After high through-put sequencing, a total of 39 912 371 clean reads were obtained (SRA accession:SRR9113366, SRR9113367). The clean reads were then assembled into 91 118 unigenes. A total of 55 830 unigenes were annotated by a similarity search against NR, Swiss-Port, GO, COG, KEGG five public databases. Base on KEGG annotation and differentially expressed genes, totally 129 catalytic enzyme genes referring to the terpenoid biosynthesis were identified, including 91 terpenoid backbone biosynthesis genes, 32 terpene synthases, and 6 cytochrome P450 (CYP450) genes. Among them, 25 genes were differentially expressed. The expression of four enzyme genes in MVA pathway in leaves were higher than that in buds, while the five enzyme genes in MEP pathway were lower in leaves than that in buds. In addition, 10 genes were highly expressed in leaves, and nine genes were highly expressed in buds. According to the high expression of differentially expressed HMGR, TPS, AS, CYP450 genes in buds, it was speculated that these genes may be related to the high content of terpenoids in flower buds. Conclusion This work obtained candidate key enzyme genes that may be involved in the biosynthesis of terpenoid by transcriptome sequencing. The results laid a foundation for further elucidating the molecular mechanism of terpenoid biosynthetic pathway in T. farfara.

R282.12

山西省国际科技合作项目（批准号：2012081045-1）；山西省现代农业产业技术体系建设专项；山西省中药现代化关键技术研究振东专项（2016ZD0108）；山西省重点研发计划（201803D221012-6）；山西中医药大学科技创新团队项目（2018-TD-009）；云南省人才培养项目（2014HB062）