Xinjiang Production and Construction Corps Key Laboratory of Oasis Town and Mountain-basin System Ecology, College of Life Science, Shihezi University, Shihezi, Xinjiang 832003, China.
Xinjiang Production and Construction Corps Key Laboratory of Oasis Town and Mountain-basin System Ecology, College of Life Science, Shihezi University, Shihezi, Xinjiang 832003, China.
Plant Sci. 2023 Jul;332:111704. doi: 10.1016/j.plantsci.2023.111704. Epub 2023 Apr 8.
Drought is an important factor limiting the yield and quality of cotton. In the present study, the gene encoding the cotton calcium-dependent protein kinase GhCDPK4 was identified and characterized in the transcriptome of cotton under PEG-induced drought stress. In RT-qPCR experiments, GhCDPK4 expression was found to be up-regulated under drought and abscisic acid (ABA) stress. Under drought conditions, heterologous overexpression of GhCDPK4 in tobacco showed a better phenotypic status, higher antioxidant enzyme activity, and lower relative electrolyte leakage (REL) and malondialdehyde (MDA) content. Meanwhile, ghcdpk4-silenced cotton plants, which were extremely sensitive to drought, exhibited higher levels of O，HO, and MDA contents compared to the control. Meanwhile, silenced lines showed impaired stomatal closure under drought stress, resulting in increased water loss from transpiration in silenced lines. GhCDPK4 expression was induced by ABA, and there are five ABA-responsive elements in its promoter. and C2-DOMAIN ABA-RELATED 4(CAR4, Gh_D09G1653) were found to interact and be co-expressed in the GhCDPK4 interaction network. Therefore, GhCDPK4 may reduce the extent of water loss and oxidative damage in cotton under drought by positively regulating ABA-controlled stomatal closure and reactive oxygen species (ROS) scavenging systems. This study demonstrates the great potential of GhCDPK4 in improving drought resistance in crops.
干旱是限制棉花产量和品质的重要因素。本研究在 PEG 诱导的干旱胁迫下对棉花转录组进行分析，鉴定并表征了编码棉花钙依赖蛋白激酶 GhCDPK4 的基因。在 RT-qPCR 实验中，发现 GhCDPK4 在干旱和脱落酸（ABA）胁迫下表达上调。在干旱条件下，GhCDPK4 在烟草中的异源过表达表现出更好的表型状态、更高的抗氧化酶活性，以及更低的相对电解质渗透率（REL）和丙二醛（MDA）含量。同时，对干旱极为敏感的 GhCDPK4 沉默棉花植株表现出更高的 O、HO 和 MDA 含量，与对照相比。同时，沉默系在干旱胁迫下表现出气孔关闭受损，导致蒸腾失水增加。GhCDPK4 的表达受 ABA 诱导，其启动子中有五个 ABA 响应元件。并且发现 C2-DOMAIN ABA-RELATED 4（CAR4，Gh_D09G1653）在 GhCDPK4 相互作用网络中相互作用并共表达。因此，GhCDPK4 可能通过正向调节 ABA 控制的气孔关闭和活性氧（ROS）清除系统，减少棉花在干旱下的水分损失和氧化损伤。本研究表明 GhCDPK4 在提高作物抗旱性方面具有巨大潜力。
