Salt Tolerance Conferred by Overexpression of a Vacuolar Na + /H + Antiport in Arabidopsis

Agricultural productivity is severely affected by soil salinity. One possible mechanism by which plants could survive salt stress is to compartmentalize sodium ions away from the cytosol. Overexpression of a vacuolar Na + /H + antiport from Arabidopsis thaliana in Arabidopsis plants promotes sustained growth and development in soil watered with up to 200 millimolar sodium chloride. This salinity tolerance was correlated with higher-than-normal levels of AtNHX1 transcripts, protein, and vacuolar Na + /H + (sodium/proton) antiport activity. These results demonstrate the feasibility of engineering salt tolerance in plants.