Poster: Hormones

Abs # 624: A novel abscisic acid catabolite in Brassica napus

Presenter:	Zhou, Rong , rong.zhou@nrc-cnrc.gc.ca
Authors	Zhou, Rong  (A) (B)  Ambrose, Stephen J (A)   Galka, Marek M (A)   Squires, Timothy M (A)   Abrams, Suzanne R (A)   Cutler, Adrian J (A)
Affiliations:	(A): Plant Biotechnology Institute, National Research Council Canada (B): Department of Chemistry, University of Saskatchewan

To understand the role of abscisic acid (ABA) metabolism during Brassica napus silique maturation, we analyzed levels of ABA and its metabolites in seeds and seed pods during development. We measured the levels of ABA, ABA-glucose ester, phaseic acid, dihydrophaseic acid and 7'-hydroxy ABA. In addition, we have identified a novel ABA catabolite. To elucidate the structure of this new metabolite, we performed feeding studies with (+)-ABA deuterated at specific positions, and analyzed the catabolites by mass spectrometry. The structure of this novel metabolite was confirmed by synthesis. The importance of this catabolite in ABA metabolism will be discussed.