植物脂肪酸去饱和酶及其编码基因研究进展

脂肪酸去饱和酶是催化脂肪酸链特定位置形成双键和产生不饱和脂肪酸的酶类。植物脂肪酸去饱和酶主要有5种(FAD2、FAD3、FAD6、FAD7和FAD8), 可分为ω-3型 (FAD2、FAD6)和ω-6型(FAD3、FAD7、FAD8)两大类。其编码基因(FAD2、FAD3、FAD6、FAD7和FAD8)在植物中一般有多个拷贝。同种基因在不同植物中拷贝数不同, 同一植物中相同基因的不同拷贝间在序列特征、表达调控和功能等方面也存在显著差异。本文根据国内外对脂肪酸去饱和酶基因及编码产物的研究现状, 分别从它们的分类、拷贝数、结构、作用机制、表达调控等方面的研究进展进行了详细的分类阐述。

An Overview of Plant Fatty Acid Desaturases and the Coding Genes

Fatty acid desaturases catalyze the insertion of a double bond at the delta position of fatty acids. At least 5 fatty acid desaturases exist in plants: FAD2, FAD3, FAD6, FAD7 and FAD8. They are categorized into two classes according to the doublebond position introduced (i.e., w-3 including FAD3, FAD7 and FAD8, and w-6 including FAD2 and FAD6). Most plant cells contain more than one copy of each gene — FAD2, FAD3, FAD6, FAD7, FAD8 — for fatty acid desaturase. The copy number of a desaturase gene varies among plant species. Even for the same gene in the same plant, different copies may vary in sequence, expression regulation and function. We provide an overview of the research advances into fatty acid desaturases in terms of their classification,copy number, gene structure, gene function, gene regulation and applications in plants.