Zheng Ying, Moorlach Benjamin, Jakobs-Schönwandt Desiree, Patel Anant, Pastacaldi Chiara, Jacob Stefan, Sede Ana R, Heinlein Manfred, Poranen Minna M, Kogel Karl-Heinz, Ladera Carmona Maria
Institute of Phytopathology, Research Centre for BioSystems, Land Use and Nutrition, Justus Liebig University Giessen, Heinrich-Buff-Ring 26, 35392, Giessen, Germany.
Fermentation and Formulation of Biologicals and Chemicals, Bielefeld Institute of Applied Materials Research, Bielefeld University of Applied Sciences, Interaktion 1, 33619, Bielefeld, Germany.
Commun Biol. 2025 Jan 25;8(1):121. doi: 10.1038/s42003-025-07554-6.
In vertebrates and plants, dsRNA plays crucial roles as PAMP and as a mediator of RNAi. How higher fungi respond to dsRNA is not known. We demonstrate that Magnaporthe oryzae (Mo), a globally significant crop pathogen, internalizes dsRNA across a broad size range of 21 to about 3000 bp. Incubation of fungal conidia with 10 ng/µL dsRNA, regardless of size or sequence, induced aberrant germ tube elongation, revealing a strong sequence-unspecific effect of dsRNA in this fungus. Accordingly, the synthetic dsRNA analogue poly(I:C) and dsRNA of various sizes and sequences elicited canonical fungal stress pathways, including nuclear accumulation of the stress marker mitogen-activated protein kinase Hog1p and production of ROS. Leaf application of dsRNA to the cereal model species Brachypodium distachyon suppressed the progression of leaf blast disease. Notably, the sequence-unspecific effect of dsRNA depends on higher doses, while pure sequence-specific effects were observed at low concentrations of dsRNA ( < 0.03 ng/µL). The protective effects of dsRNA were further enhanced by maintaining a gap of at least seven days between dsRNA application and inoculation, and by stabilising the dsRNA in alginate-chitosan nanoparticles. Overall, our study opens up additional possibilities for the development and use of dsRNA pesticides in agriculture.
在脊椎动物和植物中，双链RNA（dsRNA）作为病原体相关分子模式（PAMP）以及RNA干扰（RNAi）的介导因子发挥着关键作用。高等真菌如何响应dsRNA尚不清楚。我们证明，稻瘟病菌（Mo）作为一种对全球作物具有重要影响的病原体，能够摄取大小范围在21至约3000 bp的dsRNA。用10 ng/µL的dsRNA孵育真菌分生孢子，无论其大小或序列如何，都会诱导异常的芽管伸长，这揭示了dsRNA在这种真菌中具有强烈的序列非特异性效应。相应地，合成的dsRNA类似物聚肌苷酸胞苷酸（poly(I:C)）以及各种大小和序列的dsRNA引发了典型的真菌应激途径，包括应激标记物丝裂原活化蛋白激酶Hog1p的核积累和活性氧（ROS）的产生。将dsRNA施用于禾本科模式植物短柄草的叶片上，可抑制叶瘟病的进展。值得注意的是，dsRNA的序列非特异性效应取决于较高剂量，而在低浓度dsRNA（<0.03 ng/µL）下观察到了纯序列特异性效应。通过在dsRNA施用和接种之间保持至少七天的间隔，并将dsRNA稳定在海藻酸钠-壳聚糖纳米颗粒中，dsRNA的保护作用进一步增强。总体而言，我们的研究为农业中dsRNA农药的开发和使用开辟了更多可能性。
