Journal Article

Level of Glutathione is Regulated by ATP-Dependent Ligation of Glutamate and Cysteine through Photosynthesis in <i>Arabidopsis thaliana</i>: Mechanism of Strong Interaction of Light Intensity with Flowering

Ken’ichi Ogawa, Aya Hatano-Iwasaki, Mototsugu Yanagida and Masaki Iwabuchi

in Plant and Cell Physiology

Published on behalf of Japanese Society of Plant Physiologists

Volume 45, issue 1, pages 1-8
Published in print January 2004 | ISSN: 0032-0781
Published online January 2004 | e-ISSN: 1471-9053 | DOI: http://dx.doi.org/10.1093/pcp/pch008
Level of Glutathione is Regulated by ATP-Dependent Ligation of Glutamate and Cysteine through Photosynthesis in Arabidopsis thaliana: Mechanism of Strong Interaction of Light Intensity with Flowering

More Like This

Show all results sharing these subjects:

  • Biochemistry
  • Molecular and Cell Biology
  • Plant Sciences and Forestry

GO

Show Summary Details

Preview

Glutathione (GSH) is associated with flowering in Arabidopsis thaliana, but how GSH biosynthesis is regulated to control the transition to flowering remains to be elucidated. Since the key reaction of GSH synthesis is catalyzed by γ-glutamylcysteine synthetase (γ-ECS) and all the γ-ECS cDNAs examined contained extra sequences for plastid targeting, we investigated the relationships among GSH levels, photosynthesis and flowering. The GSH level in Arabidopsis increased with the light intensity. The ch1 mutants defective in a light-harvesting antenna in photosystem II showed reduced GSH levels with accumulation of the GSH precursor cysteine, and introduction of the γ-ECS gene GSH1 under the control of the cauliflower mosaic virus 35S promoter (35S-GSH1) into the ch1 mutant altered the GSH level in response to the γ-ECS mRNA level. These indicate that photosynthesis limits the γ-ECS reaction to regulate GSH biosynthesis. Like the glutathione-biosynthesis-defective cad2-1 mutant, the ch1 mutants flowered late under weak-light conditions, and this late-flowering phenotype was rescued by supplementation of GSH. Introduction of the 35S-GSH1 construct into the ch1 mutant altered flowering in response to the γ-ECS mRNA and GSH levels. These findings indicate that flowering in A. thaliana is regulated by the γ-ECS reaction of GSH synthesis that is coupled with photosynthesis.

Keywords: Keywords: Flowering — γ-Glutamylcysteine synthetase — Glutathione — Redox — Photosynthesis.; Abbreviations: γ-ECS, γ-glutamylcysteine synthetase; GSH, reduced glutathione; GSSG, oxidized glutathione; TCA trichloroacetic acid.

Journal Article.  5010 words.  Illustrated.

Subjects: Biochemistry ; Molecular and Cell Biology ; Plant Sciences and Forestry

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.