Overexpression of Nuclear Factor Y subunit StNF-YA7 enhances drought tolerance in potato

Abstract

Drought, the most devastating abiotic stress, has detrimental effects on crop production. To minimize such adverse effects, it is crucial to improve drought tolerance in crops. Several members of the plant Nuclear Factor Y (NF-Y) gene family are involved in drought tolerance. In this study, we isolated the potato NF-Y subunit A 7 (StNF-YA7) gene from Solanum tuberosum ‘Superior’ and analyzed its relationship to abiotic stress tolerance. StNF-YA7 was induced by drought, salt stress, and abscisic acid (ABA), and a transient expression assay using 35S:StNF-YA7-smGFP showed that StNF-YA7 is localized to the nucleus, as reported for other plant NF-Ys. To examine the involvement of StNF-YA7 in drought tolerance, we generated 35S:StNF-YA7 transgenic potato plants. The transgenic potato plants exhibited enhanced drought tolerance, likely due to reduced leaf water loss. Analysis of the StNF-YA7 promoter (pStNF-YA7) fused to GUS revealed that StNF-YA7 is strongly expressed in vascular tissue. Taken together, these results suggest that enhancing drought tolerance via StNF-YA7 overexpression is associated with reduced leaf water loss, likely through mechanism(s) involving the vascular system.