TY - JOUR
T1 - Genetic Analysis of Salt Tolerance in Arabidopsis
T2 - Evidence for a Critical Role of Potassium Nutrition
AU - Zhu, Jian Kang
AU - Liu, Jiping
AU - Xiong, Liming
N1 - Funding information:
We thank Drs. Hans Bohnert, Robert Leonard, and Ray Bressan for helpful discussions and Lei Ding and Shaw-Jye Wu for excellent technical assistance. This work was supported by a grant from the U.S. Department of Agriculture National Research Initiative Competitive Grants to J.-K.Z.
Publisher copyright:
© 1998 American Society of Plant Physiologists
PY - 1998/7
Y1 - 1998/7
N2 - A large genetic screen for sos (for salt overly sensitive) mutants was performed in an attempt to isolate mutations in any gene with an sos phenotype. Our search yielded 28 new alleles of sos1, nine mutant alleles of a newly identified locus, SOS2, and one allele of a third salt tolerance locus, SOS3. The sos2 mutations, which are recessive, were mapped to the lower arm of chromosome V, ~2.3 centimorgans away from the marker PHYC. Growth measurements demonstrated that sos2 mutants are specifically hypersensitive to inhibition by Na+ or Li+ and not hypersensitive to general osmotic stresses. Interestingly, the SOS2 locus is also necessary for K+ nutrition because sos2 mutants were unable to grow on a culture medium with a low level of K+. The expression of several salt-inducible genes was superinduced in sos2 plants. The salt tolerance of sos1, sos2, and sos3 mutants correlated with their K+ tissue content but not their Na+ tissue content. Double mutant analysis indicated that the SOS genes function in the same pathway. Based on these results, a genetic model for salt tolerance mechanisms in Arabidopsis is presented in which SOS1, SOS2, and SOS3 are postulated to encode regulatory components controlling plant K+ nutrition that in turn is essential for salt tolerance.
AB - A large genetic screen for sos (for salt overly sensitive) mutants was performed in an attempt to isolate mutations in any gene with an sos phenotype. Our search yielded 28 new alleles of sos1, nine mutant alleles of a newly identified locus, SOS2, and one allele of a third salt tolerance locus, SOS3. The sos2 mutations, which are recessive, were mapped to the lower arm of chromosome V, ~2.3 centimorgans away from the marker PHYC. Growth measurements demonstrated that sos2 mutants are specifically hypersensitive to inhibition by Na+ or Li+ and not hypersensitive to general osmotic stresses. Interestingly, the SOS2 locus is also necessary for K+ nutrition because sos2 mutants were unable to grow on a culture medium with a low level of K+. The expression of several salt-inducible genes was superinduced in sos2 plants. The salt tolerance of sos1, sos2, and sos3 mutants correlated with their K+ tissue content but not their Na+ tissue content. Double mutant analysis indicated that the SOS genes function in the same pathway. Based on these results, a genetic model for salt tolerance mechanisms in Arabidopsis is presented in which SOS1, SOS2, and SOS3 are postulated to encode regulatory components controlling plant K+ nutrition that in turn is essential for salt tolerance.
UR - http://www.scopus.com/inward/record.url?scp=0032125095&partnerID=8YFLogxK
U2 - 10.1105/tpc.10.7.1181
DO - 10.1105/tpc.10.7.1181
M3 - Journal article
C2 - 9668136
AN - SCOPUS:0032125095
SN - 1040-4651
VL - 10
SP - 1181
EP - 1191
JO - Plant Cell
JF - Plant Cell
IS - 7
ER -