Cross-kingdom RNA transfer in the barley-powdery mildew interaction

白粉病真菌是一种真菌（子囊菌）植物病原体，可感染多种被子植物，对作物和观赏植物造成严重损害。它们在专性生物营养生活方式的基础上茁壮成长，即它们需要活的寄主植物来生长和繁殖。大麦（Hordeum vulgare）与其白粉病病原菌Blumeria graminis f.sp的相互作用。hordei （Bgh）是高度共同进化的，农学相关的，在植物病理学，遗传，分子和细胞水平上具有良好的特征。最近发现的小RNA （sRNAs）在相互作用的两个伙伴中具有跨界RNA转移潜力，这提出了细胞外sRNAs调节植物白粉病战争的有趣可能性。在这里，我们提出了一个研究计划，旨在阐明细胞外sRNAs在大麦- bgh和拟南芥-戈洛维诺菌的相互作用中的作用。特别是，我们希望确定各自相互作用伙伴的srna，并在感染背景下对其进行功能表征。此外，我们希望澄清细胞外囊泡是否介导了细胞外sRNAs的相互交换，并进一步分析其中丰富的Bgh rase样效应蛋白（称为RALPHs）的推测作用。我们的研究将揭示细胞外sRNA是否以及在何种程度上在作物植物与专性生物营养病原体的相互作用中发挥作用，以及与我们研究的其他病理系统相比，宿主和微生物sRNA靶点是否保守

Powdery mildew fungi are fungal (ascomycete) phytopathogens that can infect a broad range of angiosperm plants and cause substantial damage on crop and ornamental plants. They thrive on the basis of an obligate biotrophic lifestyle, i.e. they require living host plants for growth and reproduction. The interaction between barley (Hordeum vulgare) and its powdery mildew pathogen, Blumeria graminis f.sp. hordei (Bgh), is highly-coevolved, agronomically relevant and well-characterized at the phytopathological, genetic, molecular and cellular level. The recent discovery of small RNAs (sRNAs) with cross-kingdom RNA transfer potential in both partners of the interaction raises the intriguing possibility that extracellular sRNAs modulate the plant-powdery mildew warfare. Here, we propose a research program that aims at elucidating the supposed role of extracellular sRNAs in the barley-Bgh and Arabidopsis thaliana-Golovinomyces orontii interactions. In particular, we wish to identify sRNAs of the respective interaction partners and functionally characterize them in the context of infection. In addition, we want to clarify whether extracellular vesicles mediate the presumed mutual exchange of extracellular sRNAs and further analyze the putative role of the abundant Bgh RNase-like effector proteins (termed RALPHs) therein. Our studies will reveal whether and to which extent extracellular sRNAs play a role in the interaction of a crop plant with an obligate biotrophic pathogen and if host and microbial sRNA targets are conserved in comparison to other pathosystems studied within our consortium