目的 克隆与鉴定丹参Salvia miltiorrhiza鲨烯合酶基因。方法 基于丹参基因组的基因预测结果设计引物，通过RT-PCR方法，克隆丹参鲨烯合酶基因。利用生物信息软件对基因序列进行了结构分析，对基因编码多肽进行了序列同源性比较和保守结构域分析，利用实时定量RT-PCR方法对基因进行表达模式研究。结果 通过RT-PCR方法扩增得到2个丹参鲨烯合酶基因（SmSQS1和SmSQS2），它们编码的多肽具有鲨烯合酶相关结构域和保守基序。这2个基因具有不同的外显子/内含子结构特征，具有不同的组织特异性表达模式和时间表达模式。结论 丹参基因组中存在2个鲨烯合酶基因，它们具有不同的基因结构特征和表达模式，可能在丹参甾体类和三萜类化合物生物合成中起不同作用。

Objective To clone and identify the squalene synthase genes in Salvia miltiorrhiza. Methods The primers were designed based on the predication result of S. miltiorrhiza genome genes and two squalene synthase genes (SmSQS1 and SmSQS2) from S. miltiorrhiza were amplified via RT-PCR method. Some bioinformatic methods and softwares were used for the gene structure analysis, the analyses of sequence homology and protein conserved domains of the two gene encoding polypeptides were carried. Real-time quantitative PCR (RT-qPCR) method was used for the analysis of gene expression patterns. Results The two squalene synthase genes of S. miltiorrhiza were obtained by RT-PCR method. The encoded polypeptide of the two genes has the related domains and a conserved motif for squalene synthases. The two genes had the different exon/intron characteristics and the different tissue-specific and time-specific expression patterns. Conclusion There are two squalene synthase genes existing in the genome of S. miltiorrhiza, which have the different gene structures and expression patterns, and probably play the different roles in the biosynthesis process of steroids and triterpenoids in S. miltiorrhiza.

国家自然科学基金青年基金（81102727）；国家自然科学基金面上基金（31070534）