Wheat V-H+-ATPase subunit genes significantly affect salt tolerance in Arabidopsis thaliana

Genes for V-H(+)-ATPase subunits were identified and cloned from the salt-tolerant wheat mutant RH8706-49. Sequences of these genes are highly conserved in plants. Overexpression of these genes in Arabidopsis thaliana improved its salt tolerance, and increased the activities of V-H(+)-ATPase and Na(+)/H(+) exchange, with the largest increase in plants carrying the c subunit of V-H(+)-ATPase. Results from quantitative RT-PCR analysis indicated that the mRNA level of each V-H(+)-ATPase subunit in the Arabidopsis increased under salt stress. Overall, our results suggest that each V-H(+)-ATPase subunit plays a key role in enhancing salt tolerance in plants.