Skip Navigation



JXB Advance Access published online on December 20, 2004
Journal of Experimental Botany, doi:10.1093/jxb/eri054
This Article
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
56/412/695    most recent
eri054v1
Right arrow E-letters: Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when E-letters are posted
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 PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Soudry, E.
Right arrow Articles by Gepstein, S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Soudry, E.
Right arrow Articles by Gepstein, S.
Agricola
Right arrow Articles by Soudry, E.
Right arrow Articles by Gepstein, S.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Journal of Experimental Botany © Society for Experimental Biology 2004; all rights reserved
Received June 21, 2004
Accepted October 21, 2004

RESEARCH PAPER

Accumulation and remobilization of amino acids during senescence of detached and attached leaves: in planta analysis of tryptophan levels by recombinant luminescent bacteria

Esther Soudry 1, Shimon Ulitzur 2, and Shimon Gepstein 1*

1 Faculty of Biology, Technion, Israel Institute of Technology, Haifa 32000, Israel
2 Faculty of Biotechnology and Food Engineering, Technion, Haifa 32000, Israel

* To whom correspondence should be addressed.
Shimon Gepstein, E-mail: gepstein{at}tx.technion.ac.il


  Abstract

The process of leaf senescence is biochemically characterized by the transition from nutrient assimilation to nutrient remobilization. The nutrient drain by developing vegetative and reproductive structures has been implicated in senescence induction. The steady-state levels of amino acids in senescing leaves are dependent on the rate of their release during protein degradation and on the rate of efflux into growing structures. To determine the possible regulatory role of amino acid content in leaf senescence, an in planta non-destructive, semi-quantitative method for the analysis of endogenous levels of free amino acids has been developed. The method is based on in vivo bioluminescence of amino acid-requiring strains of recombinant Escherichia coli carrying the lux gene. The luminescence signal was found to be proportional to the levels of added exogenous tryptophan and to the free amino acid levels in the plant tissues analysed. During the senescence of tobacco flowers and of detached leaves of oats and Arabidopsis, a progressive increase in the levels of free amino acids was monitored. By contrast to the detached leaves, the attached oat leaves displayed a decrease in the levels of free amino acids during senescence. In Arabidopsis, both the attached and detached leaves exhibited a similar pattern of gradual increase in amino acid content during senescence. The differences between the sink-source balance of the two species and the possible relationships between amino acid content and leaf senescence are discussed.

Keywords: Amino acids; Arabidopsis; leaf senescence; luminescent bacteria; lux system; nitrogen; sink; source.
Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 Plant Physiol.Home page
K. Kang, Y.-S. Kim, S. Park, and K. Back
Senescence-Induced Serotonin Biosynthesis and Its Role in Delaying Senescence in Rice Leaves
Plant Physiology, July 1, 2009; 150(3): 1380 - 1393.
[Abstract] [Full Text] [PDF]

Home page
 Biol LettHome page
D. Giron, W. Kaiser, N. Imbault, and J. Casas
Cytokinin-mediated leaf manipulation by a leafminer caterpillar
Biol Lett, June 22, 2007; 3(3): 340 - 343.
[Abstract] [Full Text] [PDF]

Home page
 Plant Physiol.Home page
E. van der Graaff, R. Schwacke, A. Schneider, M. Desimone, U.-I. Flugge, and R. Kunze
Transcription Analysis of Arabidopsis Membrane Transporters and Hormone Pathways during Developmental and Induced Leaf Senescence
Plant Physiology, June 1, 2006; 141(2): 776 - 792.
[Abstract] [Full Text] [PDF]

Home page
 J Exp BotHome page
S. Veljovic-Jovanovic, B. Kukavica, B. Stevanovic, and F. Navari-Izzo
Senescence- and drought-related changes in peroxidase and superoxide dismutase isoforms in leaves of Ramonda serbica
J. Exp. Bot., May 1, 2006; 57(8): 1759 - 1768.
[Abstract] [Full Text] [PDF]


Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.