College of Life Science, State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai'an, Shandong 271018, PR China.
College of Life Science, State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai'an, Shandong 271018, PR China.
J Plant Physiol. 2018 Mar;222:103-112. doi: 10.1016/j.jplph.2018.01.009. Epub 2018 Feb 1.
Drought stress is a considerable environmental factor that restrains photosynthesis. Lutein, the most prolific carotenoid in plant photosynthetic tissues, plays vital roles in the light-harvesting complexes. However, its biological functions under abiotic stresses remain unclear. In our research, transgenic tobacco plants were utilized to investigate the function of the tomato chloroplast-targeted carotenoid epsilon-ring hydroxylase (SlLUT1) in drought stress tolerance. The analysis of SlLUT1-pro-LUC and qRT-PCR showed that drought stress induced SlLUT1 expression. Transgenic tobacco plants exhibit higher lutein content than wild-type (WT) tobacco. Under drought stress, transgenic plants overexpressing SlLUT1 showed better growth performance, higher chlorophyll and relative water contents and more intact chloroplast and PSII supercomplex structures than WT tobacco. The Fv/Fm, Pn, NPQ, and content of D1 protein in transgenic plants were higher than those in WT plants under drought stress. The accumulation of HO and O decreased in transgenic tobacco plants. Moreover, transgenic plants exhibited lower MDA accumulation and REL. These results indicate that overexpression of SlLUT1 enhances tolerance to drought stress by maintaining photosynthesis and scavenging ROS in transgenic tobacco.
干旱胁迫是抑制光合作用的重要环境因素。叶黄素是植物光合组织中含量最丰富的类胡萝卜素，在光捕获复合物中发挥着重要作用。然而，其在非生物胁迫下的生物学功能尚不清楚。在我们的研究中，利用转基因烟草植物研究了番茄叶绿体靶向类胡萝卜素 ε-环羟化酶（SlLUT1）在干旱胁迫耐受中的功能。SlLUT1-pro-LUC 的分析和 qRT-PCR 显示，干旱胁迫诱导 SlLUT1 的表达。与野生型（WT）烟草相比，转基因烟草植物表现出更高的叶黄素含量。在干旱胁迫下，过表达 SlLUT1 的转基因植物表现出比 WT 烟草更好的生长表现，更高的叶绿素和相对含水量，以及更完整的叶绿体和 PSII 超复合物结构。在干旱胁迫下，转基因植物的 Fv/Fm、Pn、NPQ 和 D1 蛋白含量均高于 WT 植物。HO 和 O 的积累在转基因烟草植物中减少。此外，转基因植物表现出较低的 MDA 积累和 REL。这些结果表明，过表达 SlLUT1 通过维持光合作用和清除 ROS 来增强转基因烟草对干旱胁迫的耐受能力。
