Isolation of an Gene from That Affects ABA Import and Reduces ABA Sensitivity in

Abscisic acid (ABA) transporters are essential for the transport of ABA from its sites of synthesis to its multiple sites of action within plants and are key players in plant stress responses. Despite their importance, there is limited information on ABA transporters in crop plants. In this study, we isolated and characterized an () gene from peanut ( L.) whose cognate protein, AhATL1, is a member of the ATP-binding cassette transporter G subfamily and localizes to the plasma membrane. The expression of both the transcript and the corresponding protein were upregulated by water stress and treatment with exogenous ABA. Overexpression of in ecotype Columbia (Col) Arabidopsis () plants reduced ABA sensitivity. When and Arabidopsis Col plants were subjected to dehydration stress, the expression of () and () accumulated rapidly in rosette leaves of both lines. In contrast, while expression of () was increased in Col rosette leaves, there was no change in expression of in leaves. Similarly, water loss from detached leaves of plants was more rapid than from Col leaves. Therefore, we suggest that the function of is probably to modulate ABA sensitivity by specifically influencing ABA import into cells.