کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4570496 1332041 2012 14 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Transcriptional Activation and Production of Tryptophan-Derived Secondary Metabolites in Arabidopsis Roots Contributes to the Defense against the Fungal Vascular Pathogen Verticillium longisporum
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک دانش گیاه شناسی
پیش نمایش صفحه اول مقاله
Transcriptional Activation and Production of Tryptophan-Derived Secondary Metabolites in Arabidopsis Roots Contributes to the Defense against the Fungal Vascular Pathogen Verticillium longisporum
چکیده انگلیسی

ABSTRACTThe soil-borne fungal pathogen Verticillium longisporum causes vascular disease on Brassicaceae host plants such as oilseed rape. The fungus colonizes the root xylem and moves upwards to the foliage where disease symptoms become visible. Using Arabidopsis as a model for early gene induction, we performed root transcriptome analyses in response to hyphal growth immediately after spore germination and during penetration of the root cortex, respectively. Infected roots showed a rapid reprogramming of gene expression such as activation of transcription factors, stress-, and defense-related genes. Here, we focused on the highly coordinated gene induction resulting in the production of tryptophan-derived secondary metabolites. Previous studies in leaves showed that enzymes encoded by CYP81F2 and PEN2 (PENETRATION2) execute the formation of antifungal indole glucosinolate (IGS) metabolites. In Verticillium-infected roots, we found transcriptional activation of CYP81F2 and the PEN2 homolog PEL1 (PEN2-LIKE1), but no increase in antifungal IGS breakdown products. In contrast, indole-3-carboxylic acid (I3CA) and the phytoalexin camalexin accumulated in infected roots but only camalexin inhibited Verticillium growth in vitro. Whereas genetic disruption of the individual metabolic pathways leading to either camalexin or CYP81F2-dependent IGS metabolites did not alter Verticillium-induced disease symptoms, a cyp79b2 cyp79b3 mutant impaired in both branches resulted in significantly enhanced susceptibility. Hence, our data provide an insight into root-specific early defenses and suggest tryptophan-derived metabolites as active antifungal compounds against a vascular pathogen.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: - Volume 5, Issue 6, November 2012, Pages 1389–1402
نویسندگان
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