三烯脂肪酸在高等植物逆境胁迫应答中的作用

Role of Trienoic Fatty Acids in Higher Plants Stress Responses

三烯脂肪酸(trienoic fatty acids,TAs)是高等植物细胞膜脂中主要的不饱和脂肪酸。三烯脂肪酸不仅是膜的组成成分,而且可以调节植物对温度、盐、干旱等非生物胁迫以及病害等生物胁迫的适应性。本文介绍了高等植物三烯脂肪酸及其相应的脂肪酸去饱和酶,重点综述了三烯脂肪酸在各种逆境胁迫应答中的作用。在低温、盐、干旱等非生物逆境胁迫下,植物体中三烯脂肪酸的含量增加,以维持膜的流动性和稳定性,降低逆境对膜结构和功能的损害,从而增强植物的抗逆性。在病虫害等生物逆境胁迫下,三烯脂肪酸可能做为合成茉莉酸或其它oxylipins的前体参与植物对生物胁迫应答的防卫反应,也可能独立引发植物体产生系统获得性抗性。

Trienoic fatty acids （TAs） are the most abundant fatty acid of membrane lipid in higher plants. TAs not only serve as compents of membranes, but also regulate plant adaptation to abiotic stress and biotic stress such as temperature, salt, drought, pathogen. This review expounds on trienoic fatty acids and relevant fatty acid desaturases, and focuses on the role of trienoic fatty acids in stress responses for higher plants. When plants are confronted with abiotic stress, eg. low temperature, salt and drought stresses, the level of trienoic fatty acids increases to maintain the fluidity and stability of membrane, thus reduces the damage upon membrane structure and function. and enhances plant stress resistance. Trienoic fatty acids might be precursors for systhesis of jasmonic acide （JA） or other oxylipins involved in plant defense response to biotic stress, and could also independently trigger systemic acquired resistance （SAR） in plants.