植物根细胞离子通道研究进展

根细胞膜上存在各种离子通道.电生理学的研究表明，根细胞离子通道对于矿质吸收、转运及植物耐盐具有重要作用.该文概述了根细胞K+通道、阴离子通道和各种非选择性阳离子通道的最新研究进展，并对近期有关离子通道和植物耐盐性关系的研究进行了总结.K+通道存在于大多数的植物细胞中，其对K+的选择性远高于其他阳离子，K+通道的存在对于营养元素的吸收，尤其是K+的低亲和性吸收具有重要的意义，同时也为其他离子的出入维持了一个较为稳定的膜电势.阴离子通道激活所引起的质膜去极化可以激发非选择性的阳离子流，在盐胁迫下，可通透Cl的阴离子通道的开放是植物对胞内Cl的一种重要调控机制.由于非选择性的阳离子通道(Non-selective cation channels,NSCCs)的多样性及其对一价阳离子的低选择性，近年来NSCCs的研究受到广泛关注.NSCCs被认为参与了植物多种生理过程，包括营养元素的吸收、膨压控制、胞间转运、信号转导以及毒害离子的吸收，尤其是Na+的吸收. 

Research review on root ion channels of plants

A variety of ion channels have been identified in root cell membranes.Electrophysiological studies have shown that ion channels play an important role in mineral uptake, translocation and salt resistance. K channels, non-selective cation channels,Na\ -permeable cation channels and anion channels in roots are introduced in this review.Furthermore,the ion channel-regulated salt uptake and the contribution to salinity tolerance are briefly reviewed. K -channels,characterized in a wide variety of plant cells,are highly selective for K over other monovalent cations. They play important roles in nutrient acquisition, especially in low-affinity potassium absorption and membrane voltage control.Activation of anion channels gives rise to the depolarization of plasma membrane,and evokes non-selective currents. It is suggested that the opening of Cl -- permeable channels contribute to the regulation of net Cl -- uptake under salinity. In recent years,non-selective cation channels have attracted more attention because of their diversity and low selectivity for monovalent cations,which also implies that they are involved in a wide range of plant processes,including nutrient acquisition,turgor control,intracellular ion transport,signaling and uptake of toxic cations,especially Na .