title: Cellular and tissue distribution of potassium: physiological relevance, mechanisms and regulation.
abstract: Potassium (K(+)) is the most important cationic nutrient for all living organisms. Its cellular levels are significant (typically around 100mM) and are highly regulated. In plants K(+) affects multiple aspects such as growth, tolerance to biotic and abiotic stress and movement of plant organs. These processes occur at the cell, organ and whole plant level and not surprisingly, plants have evolved sophisticated mechanisms for the uptake, efflux and distribution of K(+) both within cells and between organs. Great progress has been made in the last decades regarding the molecular mechanisms of K(+) uptake and efflux, particularly at the cellular level. For long distance K(+) transport our knowledge is less complete but the principles behind the overall processes are largely understood. In this chapter we will discuss how both long distance transport between different organs and intracellular transport between organelles works in general and in particular for K(+). Where possible, we will provide examples of specific genes and proteins that are responsible for these phenomena.
authors.affiliation: Department of Biology, University of York, York YO10 5DD, United Kingdom.
authors.forename: Izhar
authors.initials: I
authors.lastname: Ahmad
authors.affiliation: Department of Biology, University of York, York YO10 5DD, United Kingdom. Electronic address: frans.maathuis@york.ac.uk.
authors.forename: Frans J M
authors.initials: FJ
authors.lastname: Maathuis
mesh_terms: D001692:Biological Transport; D052585:Phloem / Q000378:metabolism; D010788:Photosynthesis; D010937:Plant Growth Regulators / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism*; D018520:Plant Shoots / Q000378:metabolism; D010944:Plants / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism*; D015221:Potassium Channels / Q000378:metabolism*; D012639:Seeds / Q000378:metabolism; D013312:Stress, Physiological; D014617:Vacuoles / Q000378:metabolism; D014867:Water / Q000378:metabolism; D052584:Xylem / Q000378:metabolism
chemical_list: D010937:Plant Growth Regulators; D010940:Plant Proteins; D015221:Potassium Channels; D014867:Water; D011188:Potassium
keywords: Nutrition; Phloem; Potassium; Transport; Xylem