Molecular Cloning and Functional Identification of a Squalene Synthase Encoding Gene from Alfalfa (Medicago sativa L.)

文献类型： 外文期刊

第一作者： Kang, Junmei

作者： Kang, Junmei;Zhang, Qiaoyan;Jiang, Xu;Zhang, Tiejun;Long, Ruicai;Yang, Qingchuan;Wang, Zhen

作者机构：

关键词： alfalfa; saponins; squalene synthase; transgenic alfalfa

期刊名称：INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES （ 影响因子：5.923； 五年影响因子：6.132 ）

ISSN：

年卷期： 2019 年 20 卷 18 期

页码：

收录情况： SCI

摘要： The quality of alfalfa, a main legume forage worldwide, is of great importance for the dairy industry and is affected by the content of triterpene saponins. These natural terpenoid products of triterpene aglycones are catalyzed by squalene synthase (SQS), a highly conserved enzyme present in eukaryotes. However, there is scare information on alfalfa SQS. Here, an open reading frame (ORF) of SQS was cloned from alfalfa. Sequence analysis showed MsSQS had the same exon/intron composition and shared high homology with its orthologs. Bioinformatic analysis revealed the deduced MsSQS had two transmembrane domains. When transiently expressed, GFP-MsSQS fusion protein was localized on the plasma membrane of onion epidermal cells. Removal of the C-terminal transmembrane domain of MsSQS improved solubility in Escherichia coli. MsSQS was preferably expressed in roots, followed by leaves and stems. MeJA treatment induced MsSQS expression and increased the content of total saponins. Overexpression of MsSQS in alfalfa led to the accumulation of total saponins, suggesting a correlation between MsSQS expression level with saponins content. Therefore, MsSQS is a canonical squalene synthase and contributes to saponin synthesis in alfalfa. This study provides a key candidate gene for genetic manipulation of the synthesis of triterpene saponins, which impact both plant and animal health.

分类号：

  • 相关文献
作者其他论文 更多>>

微信小程序