摘要： 为研究二酯酰甘油酰基转移酶2（PfDGAT2）在紫苏种子油脂合成过程中的调控作用，对紫苏DGAT2基因及其编码的蛋白质进行了详细的生物信息学分析，并研究了该基因在不同紫苏品种中的表达特性。结果表明，PfDGAT2基因cDNA全长1 249 bp，共编码329个氨基酸；DGAT2蛋白的等电点为9.46，属于碱性蛋白质；二级结构预测表明，紫苏DGAT2蛋白的主要结构元件是无规则卷曲（34.65%）和α-螺旋（30.09%）；系统进化树分析表明，紫苏与芝麻和烟草的亲缘关系较近，与油橄榄的亲缘关系较远。通过研究PfDGAT2基因在含油量不同的2个紫苏品种种子发育的不同时期表达特性，结果表明，该基因在开花后30 d形成的种子中表达量最高，但是二者又具有一定差异，晋紫苏1号（含油量46.88%）表达量为开花后10 d的1.63倍，并紫苏1号（含油量35.60%）为0.75倍，因此，推测DGAT2在紫苏TAG生物合成中起重要调控作用。

关键词: 紫苏, 二酯酰甘油酰基转移酶2(DGAT2), 生物信息学, 表达特性分析

Abstract: In order to study the regulatory role of Diacylgycerol Acyltransferase 2 (PfDGAT2) in the process of oil and lipid synthesis of Perilla frutescens seeds, the structure and functions of the protein were analyzed by bioinformatics methods, and the gene expression characteristics were studied in different Perilla frutescens varieties. The results showed that PfDGAT2 gene full-length cDNA was 1 249 bp,encoding 329 amino acid. PfDGAT2 protein isoelectric point was 9.46,belonging to the basic protein. The secondary structure prediction showed that the main components of PfDGAT2 protein were random coil (34.65%) and alpha helix (30.09%). Phylogenetic tree analysis indicated that Perilla frutescens had closer genetic relationship with Sesamum indicum and Nicotiana tabacum,and had farther relationship with Olea europaea. By studying the expression characteristics of PfDGAT2 gene in two different Perilla frutescens varieties, the relationship between PfDGAT2 gene expression and oil content was analyzed. The results showed that the expression level of the gene was the highest at 30 days after flowering, but there was a certain difference between two varieties. The expression level of Jinzisu 1 (oil content 46.88%) was 1.63 times of that of 10 days after flowering, but Bingzisu 1 (oil content 35.60%) was 0.75 times.It suggested that DGAT2 gene played a major regulatory role in TAG biosynthesis of Perilla frutescens.

Key words: Perilla frutescens, Diacylgycerol acyltransferase 2(DGAT2), Bioinformatics, Expression analysis

中图分类号: 

• S565.03

• Q78