HIGS: Host-Induced Gene Silencing in the Obligate Biotrophic Fungal Pathogen Blumeria graminis

• Published in: The Plant cell Vol. 22; no. 9; pp. 3130 - 3141
• Main Authors: Nowara, Daniela, Gay, Alexandra, Lacomme, Christophe, Shaw, Jane, Ridout, Christopher, Douchkov, Dimitar, Hensel, Götz, Kumlehn, Jochen, Schweizer, Patrick
• Format: Journal Article
• Language: English
• Published: England American Society of Plant Biologists 01.09.2010
• Subjects: Airborne microorganisms; Ascomycota; Ascomycota - genetics; Barley; Blumeria graminis; double-stranded RNA; Epidermal cells; Fungi; gene expression; Gene Expression Regulation, Fungal; Genes; genetics; Hordeum; Hordeum - genetics; Hordeum - microbiology; Hordeum vulgare; Host plants; Host-Pathogen Interactions; Inoculation; Messenger RNA; metabolism; microbiology; Mildews; Molecular Sequence Data; Pathogens; plant damage; Plant protection; Plant species; Plants; Plants, Genetically Modified; Plants, Genetically Modified - genetics; Plants, Genetically Modified - microbiology; point mutation; powdery mildew; RNA; RNA Interference; RNA, Antisense; RNA, Antisense - metabolism; RNA, Double-Stranded; RNA, Double-Stranded - metabolism; RNA, Fungal; RNA, Fungal - genetics; RNA, Plant; RNA, Plant - metabolism; Triticum; Triticum - genetics; Triticum - microbiology; Triticum aestivum; virulence; Wheat
• ISSN: 1040-4651; 1532-298X; 1532-298X
• DOI: 10.1105/tpc.110.077040

Powdery mildew fungi are obligate biotrophic pathogens that only grow on living hosts and cause damage in thousands of plant species. Despite their agronomical importance, little direct functional evidence for genes of pathogenicity and virulence is currently available because mutagenesis and transformation protocols are lacking. Here, we show that the accumulation in barley (Hordeum vulgare) and wheat (Triticum aestivum) of double-stranded or antisense RNA targeting fungal transcripts affects the development of the powdery mildew fungus Blumeria graminis. Proof of concept for host-induced gene silencing was obtained by silencing the effector gene Avra10, which resulted in reduced fungal development in the absence, but not in the presence, of the matching resistance gene Mla10. The fungus could be rescued from the silencing of Avra10 by the transient expression of a synthetic gene that was resistant to RNA interference (RNAi) due to silent point mutations. The results suggest traffic of RNA molecules from host plants into B. graminis and may lead to an RNAi-based crop protection strategy against fungal pathogens.