RRC ID 4042
Author Bueso E, Alejandro S, Carbonell P, Perez-Amador MA, Fayos J, Bellés JM, Rodriguez PL, Serrano R.
Title The lithium tolerance of the Arabidopsis cat2 mutant reveals a cross-talk between oxidative stress and ethylene.
Journal Plant J.
Abstract In order to investigate the effects of a permanent increase in cellular H(2)O(2) on cation homeostasis we have studied a T-DNA insertion mutant of the Arabidopsis CATALASE 2 gene. This mutant (cat2-1) exhibits 20% of wild-type leaf catalase activity and accumulates more H(2)O(2) than the wild type under normal growth conditions. In addition to reduced size, a pale green color and great reduction in secondary roots, the cat2-1 mutant exhibited increased sensitivity to H(2)O(2), NaCl, norspermidine, high light and cold stress. On the other hand, the germination of the cat2-1 mutant is more tolerant to lithium than the wild type. This novel phenotype cannot be explained by changes in lithium transport. Actually, the uptake of lithium (and of other toxic cations such as sodium and norspermidine) is increased in the cat2-1 mutant while K(+) levels were decreased. The lithium tolerance of this mutant seems to result both from insensitivity to the inhibitory ethylene induced by this cation and a reduced capability for ethylene production. Accordingly, induction by ethylene of responsive genes such as PR4 and EBP/ERF72 is decreased in cat2-1. Mutants insensitive to ethylene such as etr1-1 and ein3-3 are lithium tolerant, and inhibition of ethylene biosynthesis with 2-aminoisobutyrate protects against lithium toxicity. Microarray analysis of gene expression indicates that the expression of genes related to cation transport and ethylene synthesis and perception was not altered in the cat2-1 mutant, suggesting that H(2)O(2) modulates these processes at the protein level. These results uncover a cross-talk between oxidative stress, cation homeostasis and ethylene.
Volume 52(6)
Pages 1052-65
Published 2007-12
DOI 10.1111/j.1365-313X.2007.03305.x
PMID 17931347
MeSH Adaptation, Physiological / drug effects Adaptation, Physiological / radiation effects Aminoisobutyric Acids / pharmacology Arabidopsis / genetics* Arabidopsis / metabolism Arabidopsis Proteins / genetics* Arabidopsis Proteins / metabolism Catalase / genetics* Catalase / metabolism Ethylenes / metabolism* Gene Expression Regulation, Plant / drug effects Gene Expression Regulation, Plant / radiation effects Genetic Complementation Test Hydrogen Peroxide / pharmacology Light Lithium Compounds / metabolism Lithium Compounds / pharmacology Mutation* Oligonucleotide Array Sequence Analysis Oxidative Stress / physiology* Phenotype Plants, Genetically Modified Reverse Transcriptase Polymerase Chain Reaction Sodium Chloride / pharmacology Transcription, Genetic / drug effects Transcription, Genetic / radiation effects
IF 5.775
Times Cited 37
Arabidopsis / Cultured plant cells, genes pda02569 pda08988