title: Regulation of Na+ and K+ homeostasis in plants: towards improved salt stress tolerance in crop plants.
abstract: Soil salinity is a major abiotic stress that results in considerable crop yield losses worldwide. However, some plant genotypes show a high tolerance to soil salinity, as they manage to maintain a high K+/Na+ ratio in the cytosol, in contrast to salt stress susceptible genotypes. Although, different plant genotypes show different salt tolerance mechanisms, they all rely on the regulation and function of K+ and Na+ transporters and H+ pumps, which generate the driving force for K+ and Na+ transport. In this review we will introduce salt stress responses in plants and summarize the current knowledge about the most important ion transporters that facilitate intra- and intercellular K+ and Na+ homeostasis in these organisms. We will describe and discuss the regulation and function of the H+-ATPases, H+-PPases, SOS1, HKTs, and NHXs, including the specific tissues where they work and their response to salt stress.
authors.affiliation: Genomics of Plant Stress Unit, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa and Instituto de Biologia Experimental e Tecnológica, Oeiras, Portugal.
authors.forename: Diego M
authors.initials: DM
authors.lastname: Almeida
authors.affiliation: Genomics of Plant Stress Unit, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa and Instituto de Biologia Experimental e Tecnológica, Oeiras, Portugal.
authors.forename: M Margarida
authors.initials: MM
authors.lastname: Oliveira
authors.affiliation: Genomics of Plant Stress Unit, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa and Instituto de Biologia Experimental e Tecnológica, Oeiras, Portugal.
authors.forename: Nelson J M
authors.initials: NJM
authors.lastname: Saibo