NHX
NHX refers to a family of Na+/H+ exchangers, transmembrane transport proteins that mediate the exchange of sodium ions for protons across cellular membranes. Members are found in bacteria, fungi, plants, and animals, with plant NHX proteins playing a prominent role in ion homeostasis and salt tolerance. In plants, NHX proteins are mainly localized to the vacuolar (tonoplast) membrane where they sequester Na+ (and to a lesser extent K+) in the vacuole, contributing to osmotic balance and pH regulation under saline conditions. A subset of NHX family members resides in the endomembrane system, including the Golgi apparatus and endosomes, where they help regulate vesicle trafficking and luminal pH.
NHX proteins function as cation/proton antiporters, using the electrochemical proton gradient generated by H+-ATPases or H+-PPases
In plants, NHX activity contributes to salt tolerance by reducing cytosolic Na+ levels and maintaining vacuolar
NHX is part of the CPA2 family of cation/proton antiporters. The best-studied plant NHX proteins are implicated