目的 克隆接骨草Sambucus chinensis 3-羟基-3-甲基戊二酰辅酶A还原酶(HMGR)基因并分析其差异表达。方法 采用RT-PCR方法获得HMGR基因cDNA序列, 并对HMGR蛋白进行理化性质、蛋白二级结构及三级结构预测分析, 并预测该蛋白功能;利用实时荧光定量PCR方法检测HMGR基因在接骨草的根状茎、地上茎、叶、花中的表达情况。结果 克隆获得的HMGR基因cDNA全长为1 626 bp, 编码593个氨基酸。生物信息学预测HMGR蛋白含2个跨膜区, 不含信号肽。HMGR基因主要在接骨草的花和地上茎中表达较高, 其他器官表达相对较低。结论 首次从接骨草中克隆了HMGR基因, 为进一步阐明该基因在接骨草萜类化合物代谢途径中的重要作用奠定基础。

Objective To clone the 3-hydroxy-3-methylglutaryl coenzyme A redutase (HMGR) gene from Sambucus chinensis and analyze the differential expression. Methods The sequence of HMGR was cloned from S. chinensis by using RT-PCR strategy. The physical and chemical properties, secondary structure, and tertiary structure of the HMGR protein were forecasted and analyzed, and its structure and function were predicted. And the different expression of HMGR gene in the rhizome, stems, leaves, and flowers was analyzed by fluorescent quantitative PCR. Results The cDNA contains a 1 782 bp open reading frame and encodes a predicted protein of 593 amino acids. Two transmembrane regions and no signal peptide were present in HMGR. Relative real-time PCR analysis indicated that HMGR showed the higher transcript abundance in the flowers and aerial stems, and the lower levels in the rhizomes and leaves. Conclusion This study clones and expression analyzes HMGR gene from S. chinensis for the first time. The results will provide a foundation for exploring the mechanism of terpenoid biosynthesis in S. chinensis.

国家自然科学基金资助项目(30870230);湖南省科技计划项目(2015SK2013, 2013FJ6090);民族药用植物资源研究与利用湖南省重点实验室开放基金项目(ZDSYSJJ2013-2)