细胞自噬提高小麦抗旱性研究

Study on Cell Autophagy Increasing Drought Resistance in Wheat

干旱胁迫可引起植物细胞发生自噬,而植物可通过自噬将体内的一些有害物质清除掉,进而提高自身的抗旱性。本研究以抗旱小麦(Triticum aestivum L.)品种平麦189号和洛旱6号以及干旱敏感小麦品种临麦2号和山农优麦3号为材料,利用溶酶体荧光探针、Western blot、透射电镜等分子生物学技术,发现抗旱小麦干旱胁迫时自噬相关基因6和8(ATG6、ATG8,autophagy related gene6/8)的表达量、ATG8-PE(磷脂酰乙醇胺)蛋白质的形成以及自噬泡的数量缓慢上升;而在干旱敏感小麦中却表现出急剧上升后下降的趋势。抗旱小麦品种细胞自噬缓慢应答干旱胁迫,且持续时间较长,使幼苗萎蔫迟缓;而干旱敏感小麦品种细胞自噬迅速应答干旱胁迫,但持续时间较短,使幼苗萎蔫加快。本研究为深入阐释小麦抗旱分子机理,筛选抗旱小麦种质资源以及培育抗旱小麦新品种提供了理论基础。

Drought stress can induce autophagy in plant cells,and plants can remove some harmful substances through autophagy,with the result of increasing their drought resistance. In this study,droughtresistant wheat cultivars Pingmai 189 and Luohan 6 Hao,and drought-vulnerable wheat cultivars Linmai 2 Hao and Shannong Youmai 3 Hao were used as materials. It was found that under drought stress the expression of autophagy-related genes 6 and 8(ATG6,ATG8,autophagy related gene 6/8),the formation of ATG8-PE(phosphatidylethanolamine)and the number of autophagic vacuoles increased slowly in the drought-tolerant cultivars,but increased sharply first and then decreased in the drought-vulnerable cultivars,as detected through the use of lysosome fluorescence probe,Western blot,transmission electron microscope and other molecular biological techniques. The slow yet long-lasting autophagy response of the droughtresistant wheat to drought stress slowed down the speed of the seedling wilting,while the fast yet shortlasting autophagy response of the drought-vulnerable wheat to drought stress speeded up the seedling wilting. This study provides a theoretical basis for further elucidating the molecular mechanism of drought resistance,screening drought-resistant wheat germplasm resources and breeding new drought-resistant wheat cultivars.