Identification of superoxide production by Arabidopsis thaliana aldehyde oxidases AAO1 and AAO3
- PDF / 488,929 Bytes
- 13 Pages / 595.276 x 790.866 pts Page_size
- 36 Downloads / 157 Views
Identification of superoxide production by Arabidopsis thaliana aldehyde oxidases AAO1 and AAO3 Maryam Zarepour • Kristina Simon • Moritz Wilch • Ute Niela¨nder • Tomokazu Koshiba Mitsunori Seo • Thomas Lindel • Florian Bittner
•
Received: 8 June 2012 / Accepted: 28 September 2012 / Published online: 14 October 2012 Ó Springer Science+Business Media Dordrecht 2012
Abstract Plant aldehyde oxidases (AOs) have gained great attention during the last years as they catalyze the last step in the biosynthesis of the phytohormone abscisic acid by oxidation of abscisic aldehyde. Furthermore, oxidation of indole-3-acetaldehyde by AOs is likely to represent one route to produce another phytohormone, indole-3-acetic acid, and thus, AOs play important roles in many aspects of plant growth and development. In the present work we demonstrate that heterologously expressed AAO1 and AAO3, two prominent members of the AO family from Arabidopsis thaliana, do not only generate hydrogen
Electronic supplementary material The online version of this article (doi:10.1007/s11103-012-9975-1) contains supplementary material, which is available to authorized users. M. Zarepour M. Wilch U. Niela¨nder F. Bittner (&) Department of Plant Biology, Braunschweig University of Technology, Humboldtstrasse 1, 38106 Braunschweig, Germany e-mail: [email protected] Present Address: M. Zarepour Department of Pediatrics, Child and Family Research Institute, University of British Columbia, 950 West 28th Ave., Vancouver, BC V5Z 4H4, Canada K. Simon T. Lindel Institute of Organic Chemistry, Braunschweig University of Technology, 38023 Braunschweig, Germany T. Koshiba Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan M. Seo Dormancy and Adaptation Research Unit, RIKEN Plant Science Center, Yokohama, Kanagawa 230-0045, Japan
peroxide but also superoxide anions by transferring aldehyde-derived electrons to molecular oxygen. In support of this, superoxide production has also been found for native AO proteins in Arabidopsis leaf extracts. In addition to their aldehyde oxidation activity, AAO1 and AAO3 were found to exhibit NADH oxidase activity, which likewise is associated with the production of superoxide anions. According to these results and due to the fact that molecular oxygen is the only known physiological electron acceptor of AOs, the production of hydrogen peroxide and/ or superoxide has to be considered in any physiological condition in which aldehydes or NADH serve as substrate for AOs. In this respect, conditions such as natural senescence and stress-induced stomatal movement, which both require simultaneously elevated levels of abscisic acid and hydrogen peroxide/superoxide, are likely to benefit from AOs in two ways, namely by formation of abscisic acid and by concomitant formation of reactive oxygen species. Keywords Aldehyde oxidase AAO1 AAO3 Superoxide Reactive oxygen species Abscisic acid Abbreviations ABA Abscisic acid AO Aldehyde oxidase DCIP 2,6-dichloroindophenol DPI Diphenyle
Data Loading...
