Plant Physiol. Illumina
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

Plant Physiology Preview
Published on February 9, 2007; 10.1104/pp.106.094771

OPEN ACCESS ARTICLE
This Article
Free via Open Access: OA
Right arrow Full Text (Plant Physiology Preview (PDF))
Right arrow Supplemental Data
Right arrowOA All Versions of this Article:
143/4/1720    most recent
pp.106.094771v2
pp.106.094771v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Web of Science (20)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Abbasi, A.-R.
Right arrow Articles by Voll, L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Abbasi, A.-R.
Right arrow Articles by Voll, L.
Agricola
Right arrow Articles by Abbasi, A.-R.
Right arrow Articles by Voll, L.

Received December 14, 2006
Accepted February 2, 2007

Specific Roles of {alpha}- and {gamma}-tocopherol in Abiotic Stress Responses of Transgenic Tobacco (Nicotiana tabacum L.)

Ali-Reza Abbasi , Mohamad Hajirezaei , Daniel Hofius , Uwe Sonnewald , and Lars Voll *

Friedrich-Alexander-Universität Erlangen-Nürnberg, Lehrstuhl für Biochemie, Staudtstr. 5, 91058 Erlangen, Germany; Institut für Pflanzengenetik und Kulturpflanzenforschung (IPK), Corrensstrasse 3, D-06466 Gatersleben, Germany

* Corresponding author; email: lvoll{at}biologie.uni-erlangen.de.

Tocopherols are lipophilic antioxidants, which are synthesized exclusively in photosynthetic organisms. In most higher plants, {alpha} - and {gamma} -tocopherol are predominant with their ratio being under spatial and temporal control. While {alpha}-tocopherol accumulates predominantly in photosynthetic tissue, seeds are rich in {gamma} -tocopherol. To date, little is known about the specific roles of {alpha} - and {gamma} -tocopherol in different plant tissues. To study the impact of tocopherol composition and content on stress tolerance, transgenic tobacco plants constitutively silenced for homogentisate phytyltransferase (HPT) and {gamma} -tocopherol methyltransferase ( {gamma} -TMT activity were created. Silencing of HPT lead to an up to 98% reduction of total tocopherol accumulation compared to wild type. Knockdown of {gamma} -TMT resulted in an up to 95% reduction of {alpha}-tocopherol in leaves of the transgenics, which was almost quantitatively compensated by an increase in {gamma} -tocopherol.

The response of HPT and {gamma} -TMT transgenics to salt and sorbitol stress and methyl viologen treatments in comparison to wild type was studied. Each stress condition imposes oxidative stress along with additional challenges like perturbing ion homeostasis, desiccation or disturbing photochemistry, respectively. Decreased total tocopherol content increased the sensitivity of HPT:RNAi transgenics towards all tested stress conditions, whereas {gamma} -TMT silenced plants showed an improved performance when challenged with sorbitol or methyl viologen. However, salt tolerance of {gamma}-TMT transgenics was strongly decreased. Membrane damage in {gamma}-TMT transgenic plants was reduced after sorbitol and methyl viologen mediated stress, as evident by less lipid peroxidation and/ or electrolyte leakage. Therefore, our results suggest specific roles for {alpha} - and {gamma} -tocopherol in vivo.




This article has been cited by other articles:


Home page
 Eukaryot CellHome page
A. Sirikhachornkit, J. W. Shin, I. Baroli, and K. K. Niyogi
Replacement of {alpha}-Tocopherol by {beta}-Tocopherol Enhances Resistance to Photooxidative Stress in a Xanthophyll-Deficient Strain of Chlamydomonas reinhardtii
Eukaryot. Cell, November 1, 2009; 8(11): 1648 - 1657.
[Abstract] [Full Text] [PDF]

Home page
 Plant Physiol.Home page
S. Kant, Y.-M. Bi, T. Zhu, and S. J. Rothstein
SAUR39, a Small Auxin-Up RNA Gene, Acts as a Negative Regulator of Auxin Synthesis and Transport in Rice
Plant Physiology, October 1, 2009; 151(2): 691 - 701.
[Abstract] [Full Text] [PDF]

Home page
 Tree PhysiolHome page
K. Behnke, E. Kleist, R. Uerlings, J. Wildt, H. Rennenberg, and J.-P. Schnitzler
RNAi-mediated suppression of isoprene biosynthesis in hybrid poplar impacts ozone tolerance
Tree Physiol, May 1, 2009; 29(5): 725 - 736.
[Abstract] [Full Text] [PDF]

Home page
 Plant Physiol.Home page
M. Matringe, B. Ksas, P. Rey, and M. Havaux
Tocotrienols, the Unsaturated Forms of Vitamin E, Can Function as Antioxidants and Lipid Protectors in Tobacco Leaves
Plant Physiology, June 1, 2008; 147(2): 764 - 778.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
ASPB Publications PLANT PHYSIOLOGY® THE PLANT CELL
Copyright © 2007 by the American Society of Plant Biologists