Open AccessABC transporter AtABCG25 is involved in abscisic acid transport and responses
Author(s) -
Takashi Kuromori,
Takaaki Miyaji,
Hidetake Yabuuchi,
Hidetada Shimizu,
Eriko Sugimoto,
Asako Kamiya,
Yoshinori Moriyama,
Kazuo Shinozaki
Publication year - 2010
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.0912516107
Subject(s) - abscisic acid , guard cell , microbiology and biotechnology , biology , arabidopsis , transporter , intracellular , biochemistry , gene , mutant
Abscisic acid (ABA) is one of the most important phytohormones involved in abiotic stress responses, seed maturation, germination, and senescence. ABA is predominantly produced in vascular tissues and exerts hormonal responses in various cells, including guard cells. Although ABA responses require extrusion of ABA from ABA-producing cells in an intercellular ABA signaling pathway, the transport mechanisms of ABA through the plasma membrane remain unknown. Here we isolated an ATP-binding cassette (ABC) transporter gene,AtABCG25 , fromArabidopsis by genetically screening for ABA sensitivity.AtABCG25 was expressed mainly in vascular tissues. The fluorescent protein-fused AtABCG25 was localized at the plasma membrane in plant cells. In membrane vesicles derived from AtABCG25-expressing insect cells, AtABCG25 exhibited ATP-dependent ABA transport. TheAtABCG25 -overexpressing plants showed higher leaf temperatures, implying an influence on stomatal regulation. These results strongly suggest that AtABCG25 is an exporter of ABA and is involved in the intercellular ABA signaling pathway. The presence of the ABA transport mechanism sheds light on the active control of multicellular ABA responses to environmental stresses among plant cells.