| Title: | The glutathione-deficient mutant pad2-1 accumulates lower amounts of glucosinolates and is more susceptible to the insect herbivore Spodoptera littoralis |
| Author(s): | Schlaeppi K; Bodenhausen N; Buchala A; Mauch F; Reymond P; |
| Address: | "Department of Biology, University of Fribourg, Fribourg, Switzerland" |
| DOI: | 10.1111/j.1365-313X.2008.03545.x |
| ISSN/ISBN: | 1365-313X (Electronic) 0960-7412 (Linking) |
| Abstract: | "Summary Plants often respond to pathogen or insect attack by inducing the synthesis of toxic compounds such as phytoalexins and glucosinolates (GS). The Arabidopsis mutant pad2-1 has reduced levels of the phytoalexin camalexin and is known for its increased susceptibility to fungal and bacterial pathogens. We found that pad2-1 is also more susceptible to the generalist insect Spodoptera littoralis but not to the specialist Pieris brassicae. The PAD2 gene encodes a gamma-glutamylcysteine synthetase that is involved in glutathione (GSH) synthesis, and consequently the pad2-1 mutant contains about 20% of the GSH found in wild-type plants. Lower GSH levels of pad2-1 were correlated with reduced accumulation of the two major indole and aliphatic GSs of Arabidopsis, indolyl-3-methyl-GS and 4-methylsulfinylbutyl-GS, in response to insect feeding. This effect was specific to GSH, was not complemented by treatment of pad2-1 with the strong reducing agent dithiothreitol, and was not observed with the ascorbate-deficient mutant vtc1-1. In contrast to the jasmonate-insensitive mutant coi1-1, expression of insect-regulated and GS biosynthesis genes was not affected in pad2-1. Our data suggest a crucial role for GSH in GS biosynthesis and insect resistance" |
| Keywords: | "Animals Arabidopsis/genetics/*metabolism Arabidopsis Proteins/genetics/metabolism DNA, Plant/genetics Gene Expression Regulation, Plant Genotype Glucosinolates/*biosynthesis Glutamate-Cysteine Ligase/genetics/*metabolism Glutathione/*metabolism Oligonucle;" |
| Notes: | "MedlineSchlaeppi, Klaus Bodenhausen, Natacha Buchala, Antony Mauch, Felix Reymond, Philippe eng Research Support, Non-U.S. Gov't England 2008/05/10 Plant J. 2008 Sep; 55(5):774-86. doi: 10.1111/j.1365-313X.2008.03545.x. Epub 2008 May 8" |
