紫苏β-酮脂酰ACP合成酶基因家族生物信息学分析

Bioinformatics Analysis of β-ketoacyl-acyl Carrier Protein Synthase Gene Family in Perilla frutescens

紫苏作为一种新型油料作物,富含多种不饱和脂肪酸,其中,α-亚麻酸含量高达61.2%。β-酮脂酰ACP合成酶在植物脂肪酸合成中起着关键性作用。对紫苏β-酮脂酰ACP合成酶(KAS)基因家族及其编码蛋白进行了详细的生物信息学分析。结果表明,紫苏KAS家族蛋白中,KASⅡ基因编码的氨基酸数最多,KASⅢB最少,均为疏水性脂溶蛋白,无信号肽,推测该家族蛋白为非分泌型蛋白;家族蛋白都含有KAS保守结构域,属于cond-enzymes超蛋白家族,二级结构组成基本相同。系统进化树分析结果表明,紫苏KASⅠ与拟南芥KASⅠ、紫苏KASⅡ与油茶KASⅡ、紫苏KASⅢ与油茶KASⅢ亲缘关系最近,紫苏与油棕、油棕榈KAS酶家族亲缘关系较远。研究结果可为深入探究紫苏脂肪酸合成机制奠定理论基础。

Perilla frutescens is a new oil crop containing all kinds of unsaturated fatty acids in its seeds oil. The oil contains higher level of α-linolenic acid, up to 61.2%. β-ketoacyl-acyl carrier protein synthase gene family plays an important role in fatty acid synthesis in plant. In this study, the KAS family proteins were analyzed with bioinformatics tools. The results showed that KASⅡ gene encoded the maximum number of amino acids, but KASⅢ B was the least in perilla KAS family proteins. All of them were hydrophobic lipid soluble proteins without signal peptide. Thus, the protein family was predicted as non-secretory proteins. KAS protein family contained KAS conserved domain, belonging to the cond-enzymes super protein family, the secondary structure elements were similar.Phylogenetic tree analysis showed that Pf KASⅠhad close relationship with At KASⅠ, Pf KAS II and Pf KAS III had the close genetic relationship comparing with Co KASⅡand Co KASⅢ, respectively. They had the farther genetic relationship with other species. These results provided a foundation for further illustration of the fatty acid synthesis mechanism in Perilla frutescens.