Chérel Isabelle
Biochimie et Physiologie Moléculaire des Plantes, UMR 5004, Agro-M/INRA/CNRS/UM2, Montpellier, France.
J Exp Bot. 2004 Feb;55(396):337-51. doi: 10.1093/jxb/erh028.
Plant voltage-gated channels belonging to the Shaker family participate in sustained K+ transport processes at the cell and whole plant levels, such as K+ uptake from the soil solution, long-distance K+ transport in the xylem and phloem, and K+ fluxes in guard cells during stomatal movements. The attention here is focused on the regulation of these transport systems by protein-protein interactions. Clues to the identity of the regulatory mechanisms have been provided by electrophysiological approaches in planta or in heterologous systems, and through analogies with their animal counterparts. It has been shown that, like their animal homologues, plant voltage-gated channels can assemble as homo- or heterotetramers associating polypeptides encoded by different Shaker genes, and that they can bind auxiliary subunits homologous to those identified in mammals. Furthermore, several regulatory processes (involving, for example, protein kinases and phosphatases, G proteins, 14-3-3s, or syntaxins) might be common to plant and animal Shakers. However, the molecular identification of plant channel partners is still at its beginning. This paper reviews current knowledge on plant K+ channel regulation at the physiological and molecular levels, in the light of the corresponding knowledge in animal cells, and discusses perspectives for the deciphering of regulatory networks in the future.
属于摇床家族的植物电压门控通道在细胞和整株植物水平上参与持续的钾离子运输过程，例如从土壤溶液中吸收钾离子、在木质部和韧皮部中进行钾离子的长距离运输，以及在气孔运动期间保卫细胞中的钾离子通量。这里的重点是通过蛋白质-蛋白质相互作用对这些运输系统的调节。通过在植物体内或异源系统中的电生理方法，并通过与动物对应物的类比，已经提供了调节机制身份的线索。已经表明，与它们的动物同源物一样，植物电压门控通道可以组装成同四聚体或异四聚体，将由不同摇床基因编码的多肽结合在一起，并且它们可以结合与在哺乳动物中鉴定出的那些同源的辅助亚基。此外，几种调节过程（例如涉及蛋白激酶和磷酸酶、G蛋白、14-3-3蛋白或 syntaxin蛋白）可能是植物和动物摇床所共有的。然而，植物通道伙伴的分子鉴定仍处于起步阶段。本文根据动物细胞中的相应知识，综述了目前关于植物钾离子通道在生理和分子水平上调节的知识，并讨论了未来破译调节网络的前景。
