Transcriptional Activation and Production of Tryptophan-Derived Secondary Metabolites in Arabidopsis Roots Contributes to the Defense against the Fungal Vascular Pathogen Verticillium Iongisporum

作     者：Tim Iven Stefanie Konig Seema Singh Susanna A. Braus-Stromeyer Matthias Bischoff Lutz F. Tietze Gerhard H. Braus Volker Lipka Ivo Feussner Wolfgang Droge-Laser 

作者机构：Julius-Maximilians-Universitat Wurzburg Julius-von-Sachs-lnstitut Pharmazeutische Biologie Julius-von-Sachs-Platz 2 97082 Wurzburg Germany Georg-August-Universitat Albrecht-von-Haller-lnstitut fur Pflanzenwissenschaften Biochemie der Pflanze Justus-von-Liebig-Weg 11 37077 GottingenGermany Georg-August-Universitat Institut for Mikrobiologie und Genetik Molekulare Mikrobiologie und Genetik Grisebachstr. 8 37077 Gottingen Germany Georg-August-Universitat Institut for Organische und Biomolekulare Chemie AG Tietze Tammannstrasse 2 37077 Gottingen Germany Georg-August-Universitat Schwann-Schleiden-Forschungszentrum for Molekulare Zellbiologie Abteilung Zellbiologie der Pflanze Julia-Lermontowa-Weg3 37077 Gottingen Germany 

出 版 物：《Molecular Plant》 (分子植物（英文版）)

年 卷 期：2012年第5卷第6期

页      面：1389-1402页

核心收录：

学科分类：0710[理学-生物学] 071001[理学-植物学] 07[理学] 09[农学] 0904[农学-植物保护] 0901[农学-作物学] 0902[农学-园艺学] 

基　　金：supported by the DFG Research Unit 

主　　题：Verticillium Iongisporum Arabidopsis root transcriptome camalexin indole glucosinolates. 

摘      要：The soil-borne fungal pathogen Verticillium Iongisporum 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 re- sponse 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 tryp- tophan-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 PEL 1 （PEN2-LIKE1）, but no increase in antifungal IGS breakdown products. In contrast, indole-3-carboxylic acid （13CA） 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 anti- fungal compounds against a vascular pathogen.