New insights into the role of Arabidopsis RABA1 GTPases in salinity stress tolerance

Abstract

RAB11 GTPases, widely conserved members of RAB small GTPases, have evolved in a unique way in plants; plant RAB11 has notable diversity compared with animals and yeast. Recently, we have shown that members of RA BA1, a subgroup in Arabidopsis RAB11 group, are required for salinity stress tolerance. To obtain a clue to understand its underlying mechanism, here we investigate whether RA BA1 regulates sodium transport across the plasma membrane and accumulation in the vacuole. The results indicate that the raba1 quadruple mutant is not defective in the import and intracellular distribution of sodium, implying that RA BA1 members are involved in a more indirect way in the responses to salinity stress. © 2013 Landes Bioscience.