27. アブシジン酸 (ABA) および ABA アナログを用いたシロイヌナズナ種子における ABA 作用機作の研究

概要

論文の詳細を見る
Abscisic acid (ABA) is a phytohormone, which controls numerous aspects of physiological processes including seed dormancy and germination. ABA response is a consequence of ABA biosynthesis, catabolism, transport and signaling. To dissect the mode of ABA action genetically, we have taken advantage of an ABA analog, (-)-R-ABA, which weakly inhibits Arabidopsis germination. Previously we reported isolation and characterization of (-)-R-ABA-insensitive mutants. Here we report isolation of (+)-S-ABA-insensitive mutants and comparison of this mutant population with the mutants obtained from (-)-R-ABA screen. Genetic analyses of (+)-S-ABA-insensitive mutants revealed three known loci that are common with (-)-R-ABA-insensitive loci and one new locus that is not found in (-)-R-insensitive mutants. This finding is consistent with the notion that these chemicals discriminate redundant ABA response pathways. Next, to see the site of discrimination of these chemicals, recently cloned ABA 8'-hydroxylase, CYP707A, was tested in vitro whether this enzyme is able to use these chemicals as the substrate. The result showed that (+)-S-ABA, but not (-)-R-ABA, was converted into the oxidation product in heterologous yeast expression system. This indicates that the ABA 8'-hydroxylation, a predominant ABA in Arabidopsis seed, acts as one of the sites of discrimination of these chemicals. This gene family will be a powerful molecular probe to genetically dissect the redundant ABA response pathways.
植物化学調節学会の論文
2003-10-10

27. アブシジン酸 (ABA) および ABA アナログを用いたシロイヌナズナ種子における ABA 作用機作の研究

スポンサーリンク

概要

著者

関連論文

スポンサーリンク