High-affinity sodium uptake in land plants

• Published in: Plant and cell physiology 2010-01, Vol.51 (1), p.68-79
• Main Authors: Haro, R., Universidad Politecnica de Madrid (Spain), Banuelos, M.A, Rodriguez-Navarro, A
• Format: Article
• Language: English
• Subjects: ABSORCION DE SUSTANCIAS NUTRITIVAS; ABSORPTION DE SUBSTANCES NUTRITIVES; Adaptation, Physiological - physiology; Amino Acid Sequence; Barium - metabolism; Barium - toxicity; Base Sequence; Biological Transport, Active - genetics; BRYOPHYTA; Bryophyta - genetics; Bryophyta - metabolism; Cation Transport Proteins - genetics; Cation Transport Proteins - metabolism; CELL MEMBRANES; Cloning, Molecular; Ecosystem; Evolution, Molecular; Fungal Proteins - genetics; Fungal Proteins - metabolism; Gene Expression Regulation, Fungal - genetics; Gene Expression Regulation, Plant - genetics; Hepatophyta - genetics; Hepatophyta - metabolism; HKT transporters; http://www.fao.org/aos/agrovoc#c_1129; http://www.fao.org/aos/agrovoc#c_3354; http://www.fao.org/aos/agrovoc#c_5273; http://www.fao.org/aos/agrovoc#c_6139; http://www.fao.org/aos/agrovoc#c_7145; http://www.fao.org/aos/agrovoc#c_9693; Land plants; MEMBRANAS CELULARES; MEMBRANE CELLULAIRE; Molecular Sequence Data; NUTRIENT UPTAKE; Oryza - genetics; Oryza - metabolism; Osmolar Concentration; Phylogeny; Physcomitrella patens; Plant Proteins - genetics; Plant Proteins - metabolism; POACEAE; POTASIO; POTASSIUM; Potassium - metabolism; Potassium - toxicity; Salt-Tolerant Plants - metabolism; Selaginellaceae - genetics; Selaginellaceae - metabolism; SODIO; SODIUM; Sodium - metabolism; Sodium transport; Symporters - genetics; Symporters - metabolism; Triticum - genetics; Triticum - metabolism; Water-Electrolyte Balance - genetics
• ISSN: 0032-0781; 1471-9053
• DOI: 10.1093/pcp/pcp168

High-affinity Na+ uptake in plants and its mediation by HKT transporters have been studied in very few species. This study expands the knowledge of high-affinity Na+ uptake in land plants for both uptake characteristics and involvement of HKT transporters. In non-flowering plants, we analyzed the Na+ content of wild mosses, carried out experiments on K+ and Na+ uptake in the micromolar range of concentrations with the moss Physcomitrella patens and the liverwort Riccia fluitans, studied a Δhkt1 mutant of P. patens and identified the HKT genes of the lycopodiophyta (clubmoss) Selaginella moellendorffii. In flowering plants we studied Na+ uptake in the micromolar range of concentrations in 16 crop plant species, identified the HKT transporters that could mediate high-affinity Na+ uptake in several species of the Triticeae tribe, and described some characteristics of high-affinity Na+ uptake in other species. Our results suggest that high-affinity Na+ uptake occurs in most land plants. In very few of them, rice and species in the Triticeae and Aveneae tribes of the Poaceae family, it is probably mediated by HKT transporters. In other plants, high-affinity Na+ uptake is mediated by one or several transporters whose responses to the presence of K+ or Ba2+ are fundamentally different from those of HKT transporters.