Researchers from Japan’s RIKEN Center for Sustainable Resource Science (CSRS) have devised a method for improving crop quality without the use of genetically modified plants. Rather of altering plant genomes, the new method uses a spray to deliver bioactive compounds to plant cells through their leaves. The new approach might be used to help crops fight pests or become drought-resistant in less time and at a lower cost than developing genetically modified crop lines. The research was published in the ACS Nano journal.
We can directly modify genomes and generate genetically modified organisms (GMOs), including GM food, thanks to technological advancements. Making transgenic plants, on the other hand, requires time and money, and it has yet to acquire general public acceptance. Researchers at RIKEN CSRS, lead by Masaki Odahara, have created a non-GM food option that addresses these issues. Rather of altering a plant’s DNA to prevent it from expressing a certain gene, a specific bioactive molecule may be inserted into the plant to inhibit that gene on the fly. In this case, a carrier that can penetrate plant cell walls transports the bioactive molecule into the plant’s cells.
While the idea was easy, putting it into action was difficult. “We had to consider a delivery mechanism that would be realistic for farmed crops under actual agricultural settings,” adds Odahara, “in addition to inventing a means to introduce bioactive molecules into the plants.” The team came to the conclusion that the ideal technique would be to use a spray that could be quickly distributed over broad areas.
Plant cells may be penetrated by a variety of nanoparticles. Cell-penetrating peptides (CPPs) were chosen because they may target particular structures inside plant cells, such as chloroplasts. The initial task was to figure out which CPPs to use while spraying. They used a confocal laser-scanning microscope to assess the quantity of fluorescence in plant leaves at various time periods after tagging natural and synthesized CPPs with fluorescent yellow and spraying them on plant leaves. They discovered many natural CPPs that were able to penetrate into the outer layer of the leaves, and in some instances even deeper, after completing this method in normal laboratory Arabidopsis thaliana, as well as various varieties of soybeans and tomatoes.
Further investigations revealed that when plasmid DNA was linked to the CPPs, the approach worked well, and analysis revealed that genes were successfully expressed in the leaves of both A. thaliana and soybeans after being delivered into the cells through an aqueous spray. The researchers also discovered that by incorporating additional proteins and nanostructures into the spray solution, they were able to temporarily increase the number of holes in the leaves, allowing the plant to absorb more spray.
Genes may often be inserted or knocked out to boost crop output. The scientists linked RNA that interferes with fluorescent protein production to a CPP after generating a transgenic plant that overexpresses yellow fluorescence in the leaves. Spraying the leaves with this compound suppressed yellow florescence expression worked as expected. “This conclusion was significant,” Odahara adds, “since any alternative to genetic alteration must be capable of achieving the same functional effect.” Finally, when a chloroplast-targeting peptide was added to a particular CPP-RNA complex, the researchers were able to silence genes unique to chloroplasts in a similar way.
Odahara explains, “Mitochondria and chloroplasts manage most of a plant’s metabolic activities.” “Using bioactive chemicals given by spray to target these structures might help crops achieve commercially desired quality attributes. The next phase is to increase the delivery system’s efficiency. Finally, we expect that this technology may be utilized to protect crops against parasites and other damaging elements in a safe manner.”
