JXB Advance Access originally published online on May 9, 2005
Journal of Experimental Botany 2005 56(417):1785-1796; doi:10.1093/jxb/eri167
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
RESEARCH PAPER |
Suppressed expression of the apoplastic ascorbate oxidase gene increases salt tolerance in tobacco and Arabidopsis plants
1Graduate School of Environmental and Human Sciences, Meijo University, Nagoya, 468-8502, Japan
2Research Institute, Meijo University, Tempaku-ku, Nagoya, 468-8502, Japan
3Applied Biological Science, Hiroshima University, Higashi-Hiroshima 739-8528, Japan
4Faculty of Domestic Science, Nagoya Women's University, Nagoya 467-8610, Japan
5Department of Plant Biology, Cornell University, Ithaca, NY 14853, USA
* To whom correspondence should be addressed at the Research Institute of Meijo University. Fax: +81 52 832 1545. E-mail: takabe{at}ccmfs.meijo-u.ac.jp
Transgenic tobacco plants expressing the ascorbate oxidase (AAO) gene in sense and antisense orientations, and an Arabidopsis mutant in which the T-DNA was inserted into a putative AAO gene, were used to examine the potential roles of AAO for salt-stress tolerance in plants. AAO activities in the transgenic tobacco plants expressing the gene in sense and antisense orientations were, respectively, about 16-fold and 0.2-fold of those in the wild type. Under normal growth conditions, no significant differences in phenotypes were observed, except for a delay in flowering time in the antisense plants. However, at high salinity, the percentage germination, photosynthetic activity, and seed yields were higher in antisense plants, with progressively lower levels in the wild type and the sense plants. The redox state of apoplastic ascorbate in sense plants was very low even under normal growth conditions. Upon salt stress, the redox state of symplastic and apoplastic ascorbate decreased among the three types of plants, but was lowest in the sense plants. The hydrogen peroxide contents in the symplastic and apoplastic spaces were higher in sense plants, progressively lower in the wild type, followed by the antisense plants. The Arabidopsis T-DNA inserted mutant exhibited very low ascorbate oxidase activity, and its phenotype was similar to that of antisense tobacco plants. These results suggest that the suppressed expression of apoplastic AAO under salt-stress conditions leads to a relatively low level of hydrogen peroxide accumulation and a high redox state of symplastic and apoplastic ascorbate which, in turn, permits a higher seed yield.
Key words: Abiotic stress, antisense expression, apoplast, ascorbate oxidase, hydrogen peroxide, salt stress
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  E. Alos, M. Roca, D. J. Iglesias, M. I. Minguez-Mosquera, C. M. B. Damasceno, T. W. Thannhauser, J. K. C. Rose, M. Talon, and M. Cercos An Evaluation of the Basis and Consequences of a Stay-Green Mutation in the navel negra Citrus Mutant Using Transcriptomic and Proteomic Profiling and Metabolite Analysis Plant Physiology, July 1, 2008; 147(3): 1300 - 1315. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 V. Fotopoulos, M. C. De Tullio, J. Barnes, and A. K. Kanellis Altered stomatal dynamics in ascorbate oxidase over-expressing tobacco plants suggest a role for dehydroascorbate signalling J. Exp. Bot., March 1, 2008; 59(4): 729 - 737. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. M. Cervilla, B. Blasco, J. J. Rios, L. Romero, and J. M. Ruiz Oxidative Stress and Antioxidants in Tomato (Solanum lycopersicum) Plants Subjected to Boron Toxicity Ann. Bot., October 1, 2007; 100(4): 747 - 756. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. Fotopoulos, M. Sanmartin, and A. K. Kanellis Effect of ascorbate oxidase over-expression on ascorbate recycling gene expression in response to agents imposing oxidative stress J. Exp. Bot., November 1, 2006; 57(14): 3933 - 3943. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Pignocchi, G. Kiddle, I. Hernandez, S. J. Foster, A. Asensi, T. Taybi, J. Barnes, and C. H. Foyer Ascorbate Oxidase-Dependent Changes in the Redox State of the Apoplast Modulate Gene Transcript Accumulation Leading to Modified Hormone Signaling and Orchestration of Defense Processes in Tobacco Plant Physiology, June 1, 2006; 141(2): 423 - 435. [Abstract] [Full Text] [PDF]
|
|