Plant salt tolerance
Plant salt tolerance
复制标题
DOI：
10.1007/978-3-540-39402-0_10
复制
发表时间：
2004-07
期刊：
影响因子：
--
通讯作者：
V. Chinnusamy;Jian-Kang Zhu
中科院分区：
文献类型：
--
作者：
V. Chinnusamy;Jian-Kang Zhu
土壤盐碱化对作物产量和质量产生不利影响。针对耐盐作物品种的育种计划的成功受到缺乏对耐盐性的分子基础的清楚理解的限制。近年来，在盐胁迫信号转导和植物耐盐性研究方面取得了一些进展。盐胁迫诱导的胞浆钙信号由钙敏感蛋白SOS 3感知。SOS 3是组成型豆蔻酰化的，并与质膜结合。SOS 3以钙依赖性方式激活SOS 2，一种丝氨酸/苏氨酸蛋白激酶。活性SOS 3-SOS 2激酶复合物激活SOS 1，一种质膜上的Na+/H+反向转运蛋白，并上调SOS 1基因表达;这导致Na+流出和离子稳态。转基因分析表明，位于液泡膜的Na+/H+逆向转运蛋白介导钠螯合到液泡中，这形成了耐盐机制的重要组成部分。有证据表明，在盐胁迫信号转导中，可能存在一个假定的感觉性组氨酸激酶（AtHK 1）-MAPK级联反应及其负调节因子（AtMKP 1），这可能导致渗透稳态和ROS清除。ABA介导的逆境蛋白调节和植物生长对植物耐盐性也很重要，但其信号途径尚不清楚。
Soil salinity adversely affects crop productivity and quality. The success of breeding programs aimed at salinity tolerant crop varieties is limited by the lack of a clear understanding of the molecular basis of salt tolerance. Recent advances in genetic analysis ofArabidopsismutants defective in salt tolerance, and molecular cloning of these loci, have showed some insight into salt stress signaling and plant salt tolerance. Salt stress-induced cytosolic calcium signals are perceived by SOS3, which is a calcium sensor protein. SOS3 is constitutively myristoylated and associated with the plasma membrane. The SOS3 activates SOS2, a ser/thr protein kinase, in a calcium dependent manner. The active SOS3-SOS2 kinase complex activates SOS1, a Na+/H+antiporter on the plasma membrane and also upregulates SOS1 gene expression; this results inNa+efflux and ion homeostasis. Transgenic analysis showed a tonoplast-located Na+/H+antiporter mediates sodium sequestration into the vacuole, and this forms an important part of the salt tolerance mechanism. Evidence also implicates a putative osmosensory histidine kinase (AtHK1)-MAPK cascade and its negative regulators (AtMKP1) in salt stress signaling that probably leads to osmotic homeostasis and ROS scavenging. ABA-mediated regulation of stress proteins and plant growth are also important for plant salt tolerance, but the signaling pathway is poorly understood.