期刊
PLANT PHYSIOLOGY AND BIOCHEMISTRY
卷 168, 期 -, 页码 167-176出版社
ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER
DOI: 10.1016/j.plaphy.2021.09.034
关键词
Sweetpotato; beta-amylase; IbBAM1.1; ROS homeostasis; Osmotic balance; Drought and salt resistance
资金
- Shandong Agriculture Research System [SDAIT-16-03]
- Shandong Agriculture Excellent Germplasm Project [2020LZGC004]
- Qingdao Sci-tech Commissioner Project [21-4-ny-30-nsh]
- China Postdoctoral Science Foundation [2021M691368]
The novel beta-amylase gene IbBAM1.1 isolated in sweetpotato plays a crucial role in enhancing tolerance to drought and high salinity stress. Overexpression of IbBAM1.1 promotes the degradation of starch and increases the levels of osmoprotectants, leading to a balanced osmotic pressure and maintained ROS homeostasis in plants. IbBAM1.1 acts as a positive regulator in part by regulating osmoprotectant levels and activating the scavenging system to counteract abiotic stressors.
Abiotic stressors, such as drought and high salinity, seriously affect plant growth, productivity, and quality. Maintaining reactive oxygen species (ROS) homeostasis and osmotic balance plays a crucial role in abiotic stress tolerance. beta-amylase (BAM) hydrolyzes alpha-1,4-glycosidic bonds by releasing maltose from starch in the regulation of soluble sugars. However, the function and mechanism of BAMs related to abiotic stress resistance remain unclear in sweetpotato (Ipomoea batatas (L.) Lam.). In this study, we isolated a novel beta-amylase gene IbBAM1.1, which was strongly induced by PEG6000, NaCl, and maltose treatments in sweetpotato variety Yanshu25. Overexpression of IbBAM1.1 conferred enhanced tolerance to the drought and high salinity stressors in Arabidopsis thaliana. The activity of beta-amylase and the degradation of starch were promoted under drought or salt stress. Accordingly, the contents of osmoprotectants, including maltose and proline were significantly higher in the transgenic lines than those in wild type (WT) plants. Less ROS, such as H2O2 and O-2(-), accumulated in the overexpressing lines than in WT plants. Superoxide dismutase activity was strongly enhanced and the level of malondialdehyde was lower under the drought or salt treatment in transgenic plants. Taken together, these results demonstrate that IbBAM1.1 acted as a positive regulator, at least in part, by regulating the level of osmoprotectants to balance the osmotic pressure and activate the scavenging system to maintain ROS homeostasis in the plants.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据