Impact of abiotic stress on miRNA profiles in tomato-derived extracellular vesicles and their biological activity

Edible plant-derived extracellular vesicles (EVs), which are rich in bioactive macromolecules such as proteins and microRNAs (miRNAs), contribute to their health benefits. While abiotic stress induces molecular changes in plants, its impact on the secretion and composition of EVs remains poorly understood. This study isolated and characterized EVs from tomatoes under nutrient deficiency, salt stress, and drought stress, analyzing changes in protein and nucleic acid content. Digital droplet polymerase chain reaction (PCR) was used to investigate the impact on selected miRNA levels. Results showed that abiotic stress significantly increased EV secretion and protein content, with varied effects on nucleic acids and miRNAs. Specifically, salt stress decreased miR-9476 levels, weakening its inhibition of the metallothionein 1× (MT1X) gene, leading to increased zinc content in intestinal cells and reduced zinc transport. These findings suggest environmental factors can modulate the biomolecular composition and functionality of plant-derived EVs, guiding the enrichment of specific biomolecules.