Furch, A. C. U. | Search bioRxiv

bioRxiv2025

Foliar mRNA spray induces protein synthesis in monocot crop and dicot model plant species

In planta gene expression via exogenous mRNAs has a wide range of potential biotechnological applications from genome editing to plant protection and to circumventing tissue culture. Yet, regarding mRNA delivery into intact plant cells, the purity, stability and translational efficiency of exogenous mRNAs appear as obstacles for effective exogenous mRNA application. Our study investigates the potential of exogenous mRNAs in mediating protein synthesis in plant cells. We applied unformulated, unmodified green fluorescent protein (GFP)-coding mRNA to monocot (Triticum aestivum, Hordeum vulgare, Zea mays) crops and dicot model plant Arabidopsis thaliana and observed GFP signals in all species, confirming the successful uptake and translation of mRNA into protein. This approach opens possibilities for broader, GM-free applications in plant science.

plant biology↗

bioRxiv2019

Phloem-mediated spreading of SIGS-derived non-coding RNAs in Hordeum vulgare

Small (s)RNA molecules are crucial factors in the communication between hosts and their interacting pathogens/pests that can modulate both host defense and microbial virulence/pathogenicity known as cross-kingdom RNA interference (ckRNAi). Consistent with this, sRNAs and their double-stranded (ds)RNA precursors have been adopted to control plant diseases through exogenously applied RNA biopesticides, known as spray-induced gene silencing (SIGS). While RNA spray proved to be effective, the mechanisms underlying the transfer and uptake of SIGS-associated RNAs are inadequately understood. Moreover, the use of the SIGS-technology as a biopesticide will require the systemic spreading of dsRNA/siRNA signals. Our results strongly support the notion of phloem-mediated long-distance movement of SIGS-associated dsRNA and/or siRNA. These findings are significant contributions to our mechanistic understanding of RNA spray technology, as our previous data indicate that SIGS requires the processing of dsRNAs by the fungal RNAi machinery. In summary, our findings support the model that SIGS involves: (i) uptake of sprayed dsRNA by the plant (via stomata); (ii) transfer of apoplastic dsRNAs into the symplast (DCL processing into siRNAs); (iii) systemic translocation of siRNA or unprocessed dsRNA via the vascular system (phloem/xylem); (iv) uptake of apoplastic dsRNA or symplastic dsRNA/siRNA depending on the lifestyle/feeding behavior of the pathogen/pest.

plant biology↗