Abstract
Thellungiella halophila is closely related to Arabidopsis thaliana, and it shows extreme salt tolerance. T. halophila has good genetic features such as small plant size and short life cycle, moreover its genes show 90% identity with those of A. thaliana. As previous researches about salt tolerant mechanism of A. thaliana, it has been revealed that the plasma membrane Na+/H+ antiporter (SOS1), vacuolar Na+/H+ antiporter (NHX1), plasma membrane Na+ transporter (HKT1) are essential in the salt tolerance. Each mutant shows salt hyper-sensitive phenotype, conversely each overexpression plants show salt tolerance. Less NaCl is accumulated in T. halophila plants than in A. thaliana under salinity condition, suggesting that T. halophila has an efficient Na+ transport system. In this study, we determined the full-length T. halophila sequences of SOS1, NHX1, and HKT1, and analyzed their expression patterns. Furthermore, we measured the ions contents in both T. halophila and A. thaliana plants using ion-chromatography.
