Review. Message in a Bubble: Shuttling small RNAs and proteins between cells and interacting organisms using extracellular vesicles (Annu. Rev. Plant Biol.)

Small RNAs have big effects and can serve to shut down or silence gene expression. Recently, studies have found that small RNAs can contribute to plant defense beyond the boundary of the plant, by being packed into extracellular vesicles (EVs) and delivered to a pathogen. Cai et al. review our current knowledge of small RNAs and proteins that shuttle between organisms. Isolation of EVs in extracellular fluids, through differential centrifugation or capture using an EV-specific antibody, facilitates analysis of their cargo. This review focuses on the formation of EVs and their roles in plant-microbe interactions, involving EVs derived from plants or their partners. A particularly interesting application of this work stems from the ability to engineer spray-on small RNAs as a form of crop protection. (Summary by Mary Williams @PlantTeaching) Annu. Rev. Plant Biol. 10.1146/annurev-arplant-081720-010616