tailieunhanh - Báo cáo khoa hoc : Potassium channels in plant cells

Potassium (K + ) is the most abundant inorganic cation in plant cells. Unlike animals, plants lack sodium⁄potassium exchangers. Instead, plant cells have developed unique transport systems for K + accumulation and release. | IFEBS Journal MINIREVIEW Potassium channels in plant cells Ingo Dreyer1 and Nobuyuki Uozumi2 1 Plant Biophysics and Heisenberg Group of Biophysics and Molecular Plant Biology Centro de Biotecnologia y Genomica de Plantas Universidad Politecnica de Madrid Spain 2 Department of Biomolecular Engineering Graduate Schoolof Engineering Tohoku University Japan Keywords Arabidopsis thaliana K channel tetramerization voltage sensor Correspondence I. Dreyer Centro de Biotecnologia y Genomica de Plantas Universidad Politecnica de Madrid Campus de Montegancedo Carretera M-40 km 28223-Pozuelo de Alarcon Madrid Spain Fax 34 91 715 7721 Tel 34 91 336 4588 E-mail N. Uozumi Department of Biomolecular Engineering Graduate School of Engineering Tohoku University Aobayama 6-6-07 Sendai 980-8579 Japan Fax 81 22 795 7293 Tel 81 22 795 7280 E-mail uozumi@ Received 28 April 2011 revised 26 August 2011 accepted 21 September 2011 doi Potassium K is the most abundant inorganic cation in plant cells. Unlike animals plants lack sodium potassium exchangers. Instead plant cells have developed unique transport systems for K accumulation and release. An essential role in potassium uptake and efflux is played by potassium channels. Since the first molecular characterization of K channels from Arabidopsis thaliana in 1992 a large number of studies on plant potassium channels have been conducted. Potassium channels are considered to be one of the best characterized class of membrane proteins in plants. Nevertheless knowledge on plant potassium channels is still incomplete. This minireview focuses on recent developments in the research of potassium transport in plants with a strong focus on voltage-gated potassium channels. Introduction The essential mineral nutrient potassium K is the predominant inorganic ion of plant cells where it can contribute up to 10 of the dry mass 1 . K is recognized as a rate-limiting factor for