title: Dynamic regulation of the root hydraulic conductivity of barley plants in response to salinity/osmotic stress.
abstract: Salinity stress significantly reduces the root hydraulic conductivity (Lpr) of several plant species including barley (Hordeum vulgare). Here we characterized changes in the Lpr of barley plants in response to salinity/osmotic stress in detail using a pressure chamber. Salt-tolerant and intermediate barley cultivars, K305 and Haruna-nijyo, but not a salt-sensitive cultivar, I743, exhibited characteristic time-dependent Lpr changes induced by 100 mM NaCl. An identical response was evoked by isotonic sorbitol, indicating that this phenomenon was triggered by osmotic imbalances. Further examination of this mechanism using barley cv. Haruna-nijyo plants in combination with the use of various inhibitors suggested that various cellular processes such as protein phosphorylation/dephosphorylation and membrane internalization appear to be involved. Interestingly, the three above-mentioned barley cultivars did not exhibit a remarkable difference in root cell sap osmolality under hypertonic conditions, in contrast to the case of Lpr. The possible biological significance of the regulation of Lpr in barley plants upon salinity/osmotic stress is discussed.
authors: Institute of Plant Science and Resources, Okayama University, 20-1, Chuo-2-chome, Kurashiki, Okayama, 710-0046 Japan Department of Physiology, Asahikawa Medical University, 2-1-1-1, Midorigaoka-higashi, Asahikawa, Hokkaido, 078-8510 Japan These authors contributed equally to this work.
authors: Toshiyuki
authors: T
authors: Kaneko
authors: Institute of Plant Science and Resources, Okayama University, 20-1, Chuo-2-chome, Kurashiki, Okayama, 710-0046 Japan Division of Applied Biology, Faculty of Textile Science and Technology, Shinshu University, 3-15-1, Tokida, Ueda, Nagano, 386-8567 Japan These authors contributed equally to this work.
authors: Tomoaki
authors: T
authors: Horie
authors: Institute of Plant Science and Resources, Okayama University, 20-1, Chuo-2-chome, Kurashiki, Okayama, 710-0046 Japan.
authors: Yoshiki
authors: Y
authors: Nakahara
authors: Institute of Plant Science and Resources, Okayama University, 20-1, Chuo-2-chome, Kurashiki, Okayama, 710-0046 Japan.
authors: Nobuya
authors: N
authors: Tsuji
authors: Institute of Plant Science and Resources, Okayama University, 20-1, Chuo-2-chome, Kurashiki, Okayama, 710-0046 Japan.
authors: Mineo
authors: M
authors: Shibasaka
authors: Institute of Plant Science and Resources, Okayama University, 20-1, Chuo-2-chome, Kurashiki, Okayama, 710-0046 Japan kmaki@rib.okayama-u.ac.jp.
authors: Maki
authors: M
authors: Katsuhara
mesh_terms: D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D001467:Hordeum / Q000187:drug effects / Q000502:physiology*; D006982:Hypertonic Solutions / Q000494:pharmacology; D009997:Osmotic Pressure; D059828:Plant Cells / Q000187:drug effects / Q000378:metabolism; D019441:Plant Epidermis / Q000166:cytology / Q000187:drug effects; D018517:Plant Roots / Q000187:drug effects / Q000502:physiology*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D021381:Protein Transport / Q000187:drug effects; D059748:Proteolysis / Q000187:drug effects; D054712:Salinity; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological / Q000187:drug effects; D013997:Time Factors; D014867:Water / Q000502:physiology*
chemical_list: D006982:Hypertonic Solutions; D014867:Water; D012965:Sodium Chloride; D046988:Proteasome Endopeptidase Complex
keywords: Aquaporin; Barley; Osmotic stress; Root hydraulic conductivity; Salinity stress; Water transport