OPEN ACCESS ARTICLE

This Article Free via Open Access: OA OA Full Text Full Text (PDF) Supplemental Data OA All Versions of this Article: 147/1/316    most recent pp.108.115733v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Web of Science (6) Citing Articles via Google Scholar Google Scholar Articles by Less, H. Articles by Galili, G. Search for Related Content PubMed PubMed Citation Articles by Less, H. Articles by Galili, G. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Agricola Articles by Less, H. Articles by Galili, G.

SYSTEMS BIOLOGY, MOLECULAR BIOLOGY, AND GENE REGULATION

Principal Transcriptional Programs Regulating Plant Amino Acid Metabolism in Response to Abiotic Stresses^1,[W],[OA]

Department of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, Israel

Using a bioinformatics analysis of public Arabidopsis (Arabidopsis thaliana) microarray data, we propose here a novel regulatory program, combining transcriptional and posttranslational controls, which participate in modulating fluxes of amino acid metabolism in response to abiotic stresses. The program includes the following two components: (1) the terminal enzyme of the module, responsible for the first catabolic step of the amino acid, whose level is stimulated or repressed in response to stress cues, just-in-time when the cues arrive, principally via transcriptional regulation of its gene; and (2) the initiator enzyme of the module, whose activity is principally modulated via posttranslational allosteric feedback inhibition in response to changes in the level of the amino acid, just-in-case when it occurs in response to alteration in its catabolism or sequestration into different intracellular compartments. Our proposed regulatory program is based on bioinformatics dissection of the response of all biosynthetic and catabolic genes of seven different pathways, involved in the metabolism of 11 amino acids, to eight different abiotic stresses, as judged from modulations of their mRNA levels. Our results imply that the transcription of the catabolic genes is principally more sensitive than that of the biosynthetic genes to fluctuations in stress-associated signals. Notably, the only exception to this program is the metabolic pathway of Pro, an amino acid that distinctively accumulates to significantly high levels under abiotic stresses. Examples of the biological significance of our proposed regulatory program are discussed.

The author responsible for distribution of materials integral to the findings presented in this article in accordance with the policy described in the Instructions for Authors (www.plantphysiol.org) is: Gad Galili (gad.galili{at}weizmann.ac.il).

^[W] The online version of this article contains Web-only data.

^[OA] Open Access articles can be viewed online without a subscription.

www.plantphysiol.org/cgi/doi/10.1104/pp.108.115733

^* Corresponding author; e-mail gad.galili{at}weizmann.ac.il.

Received January 1, 2008; accepted March 19, 2008; published March 28, 2008.

This article has been cited by other articles:

				V. Joshi and G. Jander Arabidopsis Methionine {gamma}-Lyase Is Regulated According to Isoleucine Biosynthesis Needs But Plays a Subordinate Role to Threonine Deaminase Plant Physiology, September 1, 2009; 151(1): 367 - 378. [Abstract] [Full Text] [PDF]

				W. L. Araujo, A. Nunes-Nesi, S. Trenkamp, V. I. Bunik, and A. R. Fernie Inhibition of 2-Oxoglutarate Dehydrogenase in Potato Tuber Suggests the Enzyme Is Limiting for Respiration and Confirms Its Importance in Nitrogen Assimilation Plant Physiology, December 1, 2008; 148(4): 1782 - 1796. [Abstract] [Full Text] [PDF]

				J. R. Howarth, S. Parmar, J. Jones, C. E. Shepherd, D.-I. Corol, A. M. Galster, N. D. Hawkins, S. J. Miller, J. M. Baker, P. J. Verrier, et al. Co-ordinated expression of amino acid metabolism in response to N and S deficiency during wheat grain filling J. Exp. Bot., October 1, 2008; 59(13): 3675 - 3689. [Abstract] [Full Text] [PDF]