Fraunhofer Institute for Molecular Biology and Applied Ecology IME
Leonie Graser:
»This study reveals for the first time the secondary molecular mechanism of a sprayable dsRNA product, highlighting its precision and sustainability in crop protection.«
RNA sprays are considered a promising tool for precise and environmentally friendly crop protection. In 2023, Calantha® (active ingredient: ledprona) became the world’s first sprayable double-stranded RNA product to be approved in the United States for controlling one of the most significant pests in the potato farming industry, the Colorado potato beetle. Until now, however, the exact molecular mechanism underlying its lethal effect in insects had not been fully understood.
A recent study by GreenLight Biosciences, the Fraunhofer Institute for Molecular Biology and Applied Ecology IME, and Justus Liebig University Giessen now provides the first detailed explanation of how this novel product works. The investigated dsRNA specifically suppresses the gene encoding a key subunit of the proteasome, the cellular system responsible for degrading damaged proteins. As a result, proper proteasome assembly is disrupted.
Beyond this primary effect, the researchers uncovered a previously unknown secondary mechanism. Impaired proteasome function leads to a toxic accumulation of defective proteins in the larvae of the Colorado potato beetle, ultimately causing their death. This is the first time the complete mode of action of a sprayable dsRNA product has been elucidated at the molecular level.
These findings demonstrate the high specificity of RNA-based crop protection products and provide an essential scientific foundation for their further development. A clear understanding of how dsRNA sprays work is crucial for expanding their safe and targeted use against additional agricultural pests.