Overexpression of Auxin Binding Protein 57 from Rice (Oryza sativa L.) Increased Drought and Salt Tolerance in Transgenic Arabidopsis thaliana

Auxin plays important roles in many aspects of plant growth and development. It is known that auxin binds to auxin-binding protein (Abp57) and activates the plasma membrane H+-ATPases. In order to elucidate the biological function of rice Abp57 in plants, overexpression transgenic arabidopsis lines were generated. We found overexpression transgenic arabidopsis harbouring rice Abp57 showed tolerance to osmotic stress. Phenotypic transgenic arabidopsis showed longer roots than the wildtype when grown on 1/2 MS media supplemented with various concentrations of NaCl or PEG-6000. Besides, transgenic arabidopsis has relatively lower water loss rate, higher chlorophyll content and higher biomass when growing under osmotic stress compared to the wildtype. These results suggested that Abp57 has important roles in giving tolerance to arabidopsis against drought and salt stresses.