Rodríguez-Rosales M Pilar, Gálvez Francisco J, Huertas Raúl, Aranda M Nieves, Baghour Mourad, Cagnac Olivier, Venema Kees
Department of Biochemistry, Estación Experimental del Zaidín, CSIC, Granada, Spain.
Plant Signal Behav. 2009 Apr;4(4):265-76. doi: 10.4161/psb.4.4.7919.
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.
虽然长期以来生理生化数据表明，Na(+)/H(+)和K(+)/H(+)反向转运蛋白参与植物细胞内离子和pH调节，但确定能够发挥这些作用的反向转运蛋白编码基因却花费了很长时间。基因组测序项目现已表明，植物含有大量假定的阳离子/质子反向转运蛋白，其功能才刚刚开始研究。细胞内的NHX转运蛋白构成了植物中首个被研究的阳离子/质子交换体家族。该家族的创始成员AtNHX1被确定为重要的耐盐性决定因素，并被认为催化液泡中Na(+)的积累。然而，越来越清楚的是，该基因和家族中的其他成员在pH调节和K(+)稳态中也起着关键作用，调节从囊泡运输、细胞扩张到植物发育的过程。
