Plant NHX cation/proton antiporters.
Although physiological and biochemical data since long suggested that Na(+)/H(+) and K(+)/H(+) antiporters are involved in intracellular ion and pH regulation in plants, it has taken a long time to identify genes encoding antiporters that could fulfil these roles. Genome sequencing projects have now shown that plants contain a very large number of putative Cation/Proton antiporters, the function of which is only beginning to be studied. The intracellular NHX transporters constitute the first Cation/Proton exchanger family studied in plants. The founding member, AtNHX1, was identified as an important salt tolerance determinant and suggested to catalyze Na(+) accumulation in vacuoles. It is, however, becoming increasingly clear, that this gene and other members of the family also play crucial roles in pH regulation and K(+) homeostasis, regulating processes from vesicle trafficking and cell expansion to plant development.
Rodríguez-Rosales
M Pilar
MP
Department of Biochemistry, Estación Experimental del Zaidín, CSIC, Granada, Spain.
Gálvez
Francisco J
FJ
Huertas
Raúl
R
Aranda
M Nieves
MN
Baghour
Mourad
M
Cagnac
Olivier
O
Venema
Kees
K
D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D006706:Homeostasis; D006863:Hydrogen-Ion Concentration; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism; D027961:Potassium-Hydrogen Antiporters / Q000235:genetics / Q000378:metabolism*; D055051:Salt-Tolerant Plants / Q000235:genetics* / Q000378:metabolism; D012964:Sodium / Q000378:metabolism; D017923:Sodium-Hydrogen Exchangers / Q000235:genetics / Q000378:metabolism*; D014617:Vacuoles / Q000378:metabolism
D010940:Plant Proteins; D027961:Potassium-Hydrogen Antiporters; D017923:Sodium-Hydrogen Exchangers; D012964:Sodium; D011188:Potassium