Interaction of a plant with a fungal pathogen is an encounter with hundreds of molecules. In contrast to this, a single molecule often decides between the disease and resistance. In the present article, we describe the defense responses triggered by AvrLm1, an avirulence gene from a hemibiotrophic ascomycete, Leptosphaeria maculans, responsible for an incompatible interaction with Brassica napus. Using multiple hormone quantification and expression analysis of defense-related genes, we investigated signaling events in Rlm1 plants infected with two sister isolates of L. maculans differentiated by the presence or absence of AvrLm1. Infection with the isolate carrying AvrLm1 increased the biosynthesis of salicylic acid (SA) and induced expression of the SA-associated genes ICS1, WRKY70, and PR-1, a feature characteristic of responses to biotrophic pathogens and resistance gene-mediated resistance. In addition to SA-signaling elements, we also observed the induction of ASC2a, HEL, and CHI genes associated with ethylene (ET) signaling. Pharmacological experiments confirmed the positive roles of SA and ET in mediating resistance to L. maculans. The unusual cooperation of SA and ET signaling might be a response to the hemibiotrophic nature of L. maculans. Our results also demonstrate the profound difference between the natural host B. napus and the model plant Arabidopsis in their response to L. maculans infection.
- MeSH
- Ascomycota metabolismus MeSH
- Brassica napus účinky léků metabolismus mikrobiologie MeSH
- časové faktory MeSH
- ethyleny metabolismus MeSH
- fungální proteiny metabolismus farmakologie MeSH
- kyselina salicylová metabolismus MeSH
- listy rostlin účinky léků metabolismus mikrobiologie MeSH
- nemoci rostlin MeSH
- regulace genové exprese u hub MeSH
- signální transdukce fyziologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The larvicidal activity of extracellular metabolites of keratinophilic fungus Trichophyton mentagrophytes against Aedes aegypti larvae was determined. T. mentagrophytes was isolated from soil by the feather baiting technique. Culture filtrates (10-100 microL/mL) were found to be entomotoxic to 3rd instars larvae of A. aegypti (L3), LC(50) and LC(90) being 110 +/- 11.5 and 200 +/- 20.7 microL/mL, respectively, after 2 d. Extracellular metabolites are proteinaceous in nature and more specific to chitin of mosquito larvae. They degraded cock feather causing an average of 20.0 +/- 2.6 % loss in feather mass. Culture filtrate at 100 microL/mL produced 90 % mortality against L3 after 3 d; mortality was increased in dose- and time-dependent manner. These extracellular metabolites of T. mentagrophytes could be regarded as alternatives to synthetic insecticides.
- MeSH
- Aedes účinky léků MeSH
- chitin metabolismus MeSH
- dengue prevence a kontrola přenos MeSH
- fungální proteiny farmakologie chemie metabolismus MeSH
- hmyz - vektory účinky léků MeSH
- infekce alfaviry prevence a kontrola MeSH
- insekticidy farmakologie chemie metabolismus MeSH
- keratiny metabolismus MeSH
- larva účinky léků MeSH
- moskyti - kontrola metody MeSH
- půdní mikrobiologie MeSH
- Trichophyton chemie metabolismus MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Geografické názvy
- Indie MeSH
- MeSH
- fungální proteiny farmakologie genetika MeSH
- hem farmakologie MeSH
- kyslík farmakologie MeSH
- mitochondriální ADP/ATP-translokasy biosyntéza genetika MeSH
- regulace genové exprese u hub účinky léků MeSH
- Saccharomyces cerevisiae genetika metabolismus MeSH
- transkripční faktory farmakologie genetika MeSH
- MeSH
- Aspergillus enzymologie růst a vývoj MeSH
- autolýza MeSH
- bezbuněčný systém MeSH
- chemická precipitace MeSH
- chromatografie DEAE-celulózová MeSH
- fungální proteiny analýza farmakologie izolace a purifikace MeSH
- gelová chromatografie MeSH
- lyofilizace MeSH
- močovina farmakologie MeSH
- molekulová hmotnost MeSH
- nukleosidy farmakologie MeSH
- nukleotidy farmakologie MeSH
- ribonukleasy antagonisté a inhibitory biosyntéza metabolismus MeSH
- RNA metabolismus MeSH
- síran amonný MeSH
- spektrofotometrie MeSH
- teplota MeSH
