Na~+/H~+Antiporter and Its Relationship with Plant Salt Tolerance

Na+/H+antiporter plays an important role in plant salt toletance. There are two types of Na+/H+antiporter in plant. One is the SOS1, which localizes in plasma menbrance, the other is AtNHX1, which localized in tonoplast. The plasma menbrance Na+/H+antiporter is responsible for the transport of Na+ out of the cell, while the tonoplast Na+/H+antiporter is responsible for the transportion of Na+ from cytoplasm into vacuole. Therefore, these two types of antiporters were considered as key proteins for plant salt tolerance. Recently, many evidences have shown that overexpression of a plasma menbrance Na+/H+antiporter SOS1 and a tonoplast Na+/H+antiporter AtNHX1 can increase salt tolerance of plants. The latest progress in the study of Na+/H+antiporter and its relationship with plant salt tolerance were reviewed.