Streptomyces Extracellular Vesicles Promote Plant Defence Responses Through Direct Pathogen Inhibition and Immune Activation.
TL;DR
The results demonstrated that DL157 EVs can be internalized by plant and fungal cells and offer novel insights into the role of EVs in enhancing plant defence responses by mediating the transfer of bioactive molecules from beneficial bacteria to both phytopathogenic fungi and plant cells.
Abstract
Extracellular vesicles (EVs) play a critical role in mediating the transfer of bioactive nucleic acids and proteins between plants and pathogens. However, the involvement of EVs in interactions between plants and beneficial bacteria remains poorly understood. In this study, we isolated EVs from Streptomyces violascens DL157, a Gram-positive bacterium with strong antifungal activity, and employed molecular biology, physiological, and multi-omics analyses to investigate the role of DL157 EVs in promoting plant defence responses. The results demonstrated that DL157 EVs can be internalized by plant and fungal cells. DL157 EVs were found to inhibit the germination of fungal spores and enhance plant resistance to both fungal and bacterial pathogens by simultaneously activating salicylic acid- and jasmonic acid-dependent defence pathways. Multi-omics analysis revealed that these EVs are enriched with bioactive metabolites and proteins involved in pathogen inhibition and the induction of plant defence responses. Collectively, our findings offer novel insights into the role of EVs in enhancing plant defence responses by mediating the transfer of bioactive molecules from beneficial bacteria to both phytopathogenic fungi and plant cells.