Molecular cloning and functional characterization of MdSOS2 reveals its involvement in salt tolerance in apple callus and Arabidopsis
Molecular cloning and functional characterization of MdSOS2 reveals its involvement in salt tolerance in apple callus and Arabidopsis
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DOI：
10.1007/s00299-011-1189-5
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发表时间：
2012-04-01
影响因子：
6.2
通讯作者：
Hao, Yu-Jin
中科院分区：
文献类型：
--
作者：
Hu, Da-Gang;Li, Ming;Hao, Yu-Jin
植物通过激活“胁迫基因”来应对各种环境胁迫。CIPKs（CBL-interacting protein kinases）家族基因在应激反应过程中起重要作用。本研究从苹果（Malus x Domestica）中克隆了CIPK基因MdSOS 2。序列比对和系统发育分析表明，该基因与拟南芥AtSOS 2高度相似，含有保守的结构域和基序。表达分析表明，MdSOS 2在所有受试器官中均有不同程度的表达，且在盐胁迫下呈阳性表达。此外，异位表达的MdSOS 2补充了拟南芥sos 2突变体的功能，并赋予转基因拟南芥增强耐盐性。酵母双杂交实验表明，MdSOS 2蛋白的N端分别与MdSOS 3和AtSOS 3发生了物理相互作用，表明SOS信号通路在苹果树中起作用。在转基因苹果愈伤组织中，MdSOS 2的过表达增强，而抑制其表达则降低其耐盐性，表明MdSOS 2在苹果盐胁迫反应中起正调控作用。
Plants respond to various environmental stresses by activating "stress genes". CIPKs (CBL-interacting protein kinases) family genes play an important role in the process of stress response. In this study, a CIPK gene MdSOS2 was isolated from apple (Malus x Domestica). Sequence alignment and phylogenetic analysis showed that it is highly similar with Arabidopsis AtSOS2 and contained the conserved domains and motifs. Expression analysis demonstrated that MdSOS2 expressed in all tested organs at different levels, and positively in response to salt stress. Furthermore, the ectopic expression of MdSOS2 complemented the function of Arabidopsis sos2 mutant, and conferred enhanced salt tolerance to the transgenic Arabidopsis. Yeast two-hybrid assay indicated that the N-terminal of MdSOS2 protein physically interacted with MdSOS3 and AtSOS3, respectively, suggesting that SOS pathway operates in apple tree. Finally, MdSOS2 overexpression enhanced, while its suppression reduced the tolerance to salt in transgenic apple calluses, indicating that MdSOS2 acts as a positive regulator in response to salt stress in apple.