Project description:Resistance to agricultural fungicides in the field has created a need for discovering fungicides with new modes of action. DNA microarrays, because they provide information on expression of many genes simultaneously, could help to identify the modes of action. To begin an expression pattern database for agricultural fungicides, transcriptional patterns of Saccharomyces cerevisiae strain S288C genes were analysed following 2-h treatments with I50 concentrations of ergosterol biosynthesis inhibitors commonly used against plant pathogenic fungi. Eight fungicides, representing three classes of ergosterol biosynthesis inhibitors, were tested. To compare gene expression in response to a fungicide with a completely different mode of action, a putative methionine biosynthesis inhibitor (MBI) was also tested. Expression patterns of ergosterol biosynthetic genes supported the roles of Class I and Class II inhibitors in affecting ergosterol biosynthesis, confirmed that the putative MBI did not affect ergosterol biosynthesis, and strongly suggested that in yeast, the Class III inhibitor did not affect ergosterol biosynthesis. The MBI affected transcription of three genes involved in methionine metabolism, whereas there were essentially no effects of ergosterol synthesis inhibitors on methionine metabolism genes. There were no consistent patterns in other up- or downregulated genes between fungicides. These results suggest that inspection of gene response patterns within a given pathway may serve as a useful first step in identifying possible modes of action of fungicides. agricultural sterol biosynthesis inhibitor fungicides. Keywords = agriculture Keywords = ergosterol Keywords = methionine Keywords = fungicide Keywords = Saccharomyces cerevisiae S288C Keywords = biosynthesis
Project description:Resistance to agricultural fungicides in the field has created a need for discovering fungicides with new modes of action. DNA microarrays, because they provide information on expression of many genes simultaneously, could help to identify the modes of action. To begin an expression pattern database for agricultural fungicides, transcriptional patterns of Saccharomyces cerevisiae strain S288C genes were analysed following 2-h treatments with I50 concentrations of ergosterol biosynthesis inhibitors commonly used against plant pathogenic fungi. Eight fungicides, representing three classes of ergosterol biosynthesis inhibitors, were tested. To compare gene expression in response to a fungicide with a completely different mode of action, a putative methionine biosynthesis inhibitor (MBI) was also tested. Expression patterns of ergosterol biosynthetic genes supported the roles of Class I and Class II inhibitors in affecting ergosterol biosynthesis, confirmed that the putative MBI did not affect ergosterol biosynthesis, and strongly suggested that in yeast, the Class III inhibitor did not affect ergosterol biosynthesis. The MBI affected transcription of three genes involved in methionine metabolism, whereas there were essentially no effects of ergosterol synthesis inhibitors on methionine metabolism genes. There were no consistent patterns in other up- or downregulated genes between fungicides. These results suggest that inspection of gene response patterns within a given pathway may serve as a useful first step in identifying possible modes of action of fungicides. agricultural sterol biosynthesis inhibitor fungicides. Keywords = agriculture Keywords = ergosterol Keywords = methionine Keywords = fungicide Keywords = Saccharomyces cerevisiae S288C Keywords = biosynthesis
Project description:Plant food production is severely affected by fungi; to cope with this problem, farmers use synthetic fungicides. However, the need to reduce fungicide application has led to a search for alternatives, such as biostimulants. Rare-earth elements (REEs) are widely used as biostimulants, but their mode of action and their potential as an alternative to synthetic fungicides have not been fully studied. Here, the biostimulant effect of gadolinium (Gd) is explored using the plant-pathosystem Arabidopsis thaliana–Botrytis cinerea . We determine that Gd induces local, systemic, and long-lasting plant defense responses to B. cinerea, without affecting fungal development. The physiological changes induced by Gd have been related to its structural resemblance to calcium. However, our results show that the calcium-induced defense response is not sufficient to protect plants against B. cinerea, compared to Gd. Furthermore, a genome-wide transcriptomic analysis shows that Gd induces plant defenses and modifies early and late defense responses. However, the resistance to B. cinerea is dependent on JA/ET-induced responses. These data support the conclusion that Gd can be used as a biocontrol agent for B. cinerea. These results are a valuable tool to uncover the molecular mechanisms induced by REEs.
Project description:Septoria leaf blotch is a worldwide threat for wheat and mainly controlled by the application of synthetic fungicides. The fungal pathogen responsible for this disease, Zymoseptoria tritici, was shown as highly adaptable to its host plant, but also to fungicide challenge. Over the past decades it developed resistance to most fungicides due to target site modifications. Recently isolated strains showed cross-resistance to diverse fungicides and to unrelated drugs, suggesting a resistance mechanism that seems rarer in phytopathogenic fungi, known as multidrug resistance (MDR) in other organisms. In this study we show for two Z. tritici MDR strains, MDR6 and MDR7, enhanced prochloraz efflux sensitive to the modulators amitryptiline and chlorpromazine. Efflux was also inhibited by verapamil in the MDR7strain. Transcriptomics revealed several overexpressed transporter genes in both MDR strains, out of which the expression of the MgMFS1 transporter gene was the strongest and constitutively high in tested MDR field strains. Its inactivation in the MDR6 strain abolished resistance to fungicides with different modes of action revealing its involvement in the MDR phenomenon in Z. tritici.
Project description:Septoria leaf blotch is a worldwide threat for wheat and mainly controlled by the application of synthetic fungicides. The fungal pathogen responsible for this disease, Zymoseptoria tritici, was shown as highly adaptable to its host plant, but also to fungicide challenge. Over the past decades it developed resistance to most fungicides due to target site modifications. Recently isolated strains showed cross-resistance to diverse fungicides and to unrelated drugs, suggesting a resistance mechanism that seems rarer in phytopathogenic fungi, known as multidrug resistance (MDR) in other organisms. In this study we show for two Z. tritici MDR strains, MDR6 and MDR7, enhanced prochloraz efflux sensitive to the modulators amitryptiline and chlorpromazine. Efflux was also inhibited by verapamil in the MDR7strain. Transcriptomics revealed several overexpressed transporter genes in both MDR strains, out of which the expression of the MgMFS1 transporter gene was the strongest and constitutively high in tested MDR field strains. Its inactivation in the MDR6 strain abolished resistance to fungicides with different modes of action revealing its involvement in the MDR phenomenon in Z. tritici. A total of four strains were compared, two sensitive (IPO323, S6) and two MDR strains (09-ASA-3apz; 09-CB01) with three replicates each. All strains were grown in liquid YPD medium to exponential growth.