The SNF1-type serine-threonine protein kinase SAPK4 regulates stress-responsive gene expression in rice
The SNF1-type serine-threonine protein kinase SAPK4 regulates stress-responsive gene expression in rice
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DOI：
10.1186/1471-2229-8-49
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发表时间：
2008-04-28
影响因子：
5.3
通讯作者：
Golldack, Dortje
中科院分区：
文献类型：
--
作者：
Diedhiou, Calliste J.;Popova, Olga V.;Golldack, Dortje
背景：植物对细胞外感知的非生物胁迫，如低温、干旱和盐度，通过激活复杂的细胞内信号级联反应来调节适应的生化和生理变化。蛋白激酶是主要的信号转导因子，在真核生物适应环境变化中起着核心作用。在本研究中，我们鉴定了蔗糖非发酵1相关蛋白激酶2 (SnRK2) SAPK4在水稻盐胁迫响应中的功能。结果：SAPK4与绿色荧光蛋白（GFP）的翻译融合在细胞质和细胞核中显示亚细胞定位。为了研究SAPK4在耐盐性中的作用，我们在CaMV-35S启动子的控制下，培养了过表达SAPK4的转基因水稻植株。诱导SAPK4的表达可以促进盐胁迫下幼苗和成熟植株的萌发、生长和发育。盐胁迫下，过表达sapk4的水稻Na+和Cl-积累量减少，光合作用改善。sapk4在离子稳态和氧化应激反应中起调控作用的基因：液泡H+- atp酶、Na+/H+反转运蛋白NHX1、Cl-通道OsCLC1和过氧化氢酶。结论：盐碱胁迫下，SAPK4可调节盐胁迫下植物的离子稳态和生长发育，是植物盐胁迫适应的调控因子。鉴定与植物逆境适应有关的信号元件为鉴定具有提高作物耐受性潜力的环境变化适应机制的转录激活因子提供了一种强有力的方法。
Background: Plants respond to extracellularly perceived abiotic stresses such as low temperature, drought, and salinity by activation of complex intracellular signaling cascades that regulate acclimatory biochemical and physiological changes. Protein kinases are major signal transduction factors that have a central role in mediating acclimation to environmental changes in eukaryotic organisms. In this study, we characterized the function of the sucrose nonfermenting 1-related protein kinase2 (SnRK2) SAPK4 in the salt stress response of rice.Results: Translational fusion of SAPK4 with the green fluorescent protein (GFP) showed subcellular localization in cytoplasm and nucleus. To examine the role of SAPK4 in salt tolerance we generated transgenic rice plants with over-expression of rice SAPK4 under control of the CaMV-35S promoter. Induced expression of SAPK4 resulted in improved germination, growth and development under salt stress both in seedlings and mature plants. In response to salt stress, the SAPK4-overexpressing rice accumulated less Na+ and Cl- and showed improved photosynthesis. SAPK4-regulated genes with functions in ion homeostasis and oxidative stress response were identified: the vacuolar H+-ATPase, the Na+/H+ antiporter NHX1, the Cl- channel OsCLC1 and a catalase.Conclusion: Our results show that SAPK4 regulates ion homeostasis and growth and development under salinity and suggest function of SAPK4 as a regulatory factor in plant salt stress acclimation. Identification of signaling elements involved in stress adaptation in plants presents a powerful approach to identify transcriptional activators of adaptive mechanisms to environmental changes that have the potential to improve tolerance in crop plants.