The Arabidopsis P450 protein CYP82C2 modulates jasmonate-induced root growth inhibition, defense gene expression and indole glucosinolate biosynthesis.
Cell Res
; 20(5): 539-52, 2010 May.
Article
em En
| MEDLINE
| ID: mdl-20354503
ABSTRACT
Jasmonic acid (JA) is a fatty acid-derived signaling molecule that regulates a broad range of plant defense responses against herbivores and some microbial pathogens. Molecular genetic studies have established that JA also performs a critical role in several aspects of plant development. Here, we describe the characterization of the Arabidopsis mutant jasmonic acid-hypersensitive1-1 (jah1-1), which is defective in several aspects of JA responses. Although the mutant exhibits increased sensitivity to JA in root growth inhibition, it shows decreased expression of JA-inducible defense genes and reduced resistance to the necrotrophic fungus Botrytis cinerea . Gene cloning studies indicate that these defects are caused by a mutation in the cytochrome P450 protein CYP82C2. We provide evidence showing that the compromised resistance of the jah1-1 mutant to B . cinerea is accompanied by decreased expression of JA-induced defense genes and reduced accumulation of JA-induced indole glucosinolates (IGs). Conversely, the enhanced resistance to B. cinerea in CYP82C2-overexpressing plants is accompanied by increased expression of JA-induced defense genes and elevated levels of JA-induced IGs. We demonstrate that CYP82C2 affects JA-induced accumulation of the IG biosynthetic precursor tryptophan (Trp), but not the JA-induced IAA or pathogen-induced camalexin. Together, our results support a hypothesis that CYP82C2 may act in the metabolism of Trp-derived secondary metabolites under conditions in which JA levels are elevated. The jah1-1 mutant should thus be important in future studies toward understanding the mechanisms underlying the complexity of JA-mediated differential responses, which are important for plants to adapt their growth to the ever-changing environments.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Arabidopsis
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Raízes de Plantas
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Regulação da Expressão Gênica de Plantas
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Ciclopentanos
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Sistema Enzimático do Citocromo P-450
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Proteínas de Arabidopsis
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Oxilipinas
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Glucosinolatos
Idioma:
En
Revista:
Cell Res
Ano de publicação:
2010
Tipo de documento:
Article