Small RNAs (sRNAs) are short non-coding RNAs that mediate gene silencing in many cellular processes. We discovered that some sRNAs from eukaryotic pathogens, such as Botrytis cinerea, can move into host plant cells and suppress host immunity genes for successful infection (Weiberg et al., Science 2013). We further demonstrated that such cross-kingdom RNAi is bi-directional. Plants can also send sRNAs into pathogens using extracellular vesicles to silence fungal virulence-related genes as part of its immune responses (Cai et al., Science 2018). We found that plants have multiple classes of extracellular vesicles, and tetraspanin-positive exosomes are the major class responsible for sRNA delivery (He et al., Nature Plants 2021). Furthermore, we also discovered that many fungal pathogens can take up double-stranded RNAs (dsRNAs) and sRNAs from the environment (Wang et al,, Nature Plants, 2016). Applying sRNAs or dsRNAs that target fungal virulence-related genes on the surface of fruits, vegetables and flowers significantly inhibits fungal infection (Qiao et al., Plant Biotechnology Journal 2021). Such pathogen gene-targeting RNAs represent a new generation of fungicides that are durable and eco-friendly.
Speaker: Hailing Jin
Host: Corlett Wood
University of California Riverside