The news these days has been filled with talk about RNA technology. This genetic tool can be used – in a very targeted way – to accomplish many tasks, from the COVID-19 vaccine to controlling the Colorado potato beetle. Boston-based startup GreenLight Biosciences has mastered the fabrication of bulk RNA, and it’s creating new ways to control a range of crop profit thieves.
“Welcome to the world of RNA,” says Mark Singleton of GreenLight. “I first heard of RNA 30 years ago and was won over. I liked the promise.”
Singleton, who is senior vice president of technology and external innovation at GreenLight, was not working with RNA at the time, but he was intrigued. But using such a targeted tool presents challenges: from making “naked” RNA designed to do a specific job, to determining how to get the product on the target in such a way that it does the job. Remember that RNA has to be somehow “injected” into the insect – or the disease or the weed – in order to work. And if eating the product breaks down RNA before it can do the job, it’s of little value.
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HARD FOR BEES: The destructive varroa mite has struck beekeepers across the country. A new approach using RNA and an interesting method of administration promise better control.
GreenLight overcomes all of these problems and has been shown to be effective in field trials in controlling botrytis, a crop disease that causes food to rot. “It was a proof of concept, and we just mixed it with water and sprayed it on the disease,” Singleton recalls. “These experiments were done with bare double stranded RNA; there was no special technology, just water.” The result was strong disease control and the first use of RNA to fight botrytis.
Fight more complex parasites
GreenLight has seven products in development which it says will be cleared for use by 2026. The first two target a few pests – the first is the Colorado potato beetle, which can spread far and cause extensive damage with potatoes – and not just in Colorado.
Singleton explains that GreenLight identified double-stranded RNA targeted at a process in CPB that prevented the bug from eating. The product works, but for GreenLight to be successful, the product must also adapt to a farmer’s practices. In tests, the company shows farmers how the product works.
“We sprayed the product on the crop; it’s a simple wording, ”Singleton explains. “So the farmer has to look at the bottle. He’ll love the wording because it’s easy to handle. You can mix her into anything, and she goes in her sprayer. You can put it with your chemistry. special instructions. “
The beetle consumes the leaf product, and because it doesn’t have a straightforward approach to breaking down RNA in the gut, it passes into the insect and stops a key physical process: ending the bedbug. . Being so targeted, the product has shown no negative impact on beneficial insects in the environment.
Singleton notes that CPB usually appears around the same time of the season, so a single spray can provide control in many situations. The company is working on carrier formulations that would keep RNA on the plant longer, or using other formulations that could go directly into the insect rather than wait to be consumed.
Once the right RNA is identified, it is this delivery mechanism that makes the difference, and GreenLight is investing a lot of capital in exploring the many ways to get the job done.
Stopping varroa mites early
In honey bees, the process of dispersing RNA in a form that will stop the destructive varroa mite brings new ideas to the application.
The Varroa destructor mite has become the scourge of the beekeeping industry. Linked to colony collapse disorder and other challenges plaguing beehives, the mite clings to the bee, consuming energy from the animal – but also bringing other diseases.
Controlling the varroa mite is a challenge – due to the size of the bees, and also because insecticides that could stop the mite could injure the bee. There are targeted insecticides at work on the market, but GreenLight is relying on some of the intellectual property acquired from Bayer to innovate in controls.
The company has identified an RNA that will stop Varroa mites. But how to deliver it? While the final approach is still under development, the company’s approach is taking a different turn from that currently on the market.
“This mite is like a fist-sized lump on your chest, connected and injecting disease,” Singleton explains. “The current controls are working with this adult mite on the bee, which means the bee may already be infected with a disease.”
The GreenLight approach reaches varroa mites very early; in fact, in the brood cell with the larvae before they hatch. “We can introduce RNA to control varroa mites in bees using sugar water,” Singleton explains. “The bee uses this material to create brood food for this hive cell, and the RNA is there.”
The RNA present stops the varroa mite before it can attach itself to the bee, thereby improving the health of the hive and preventing the spread of disease. The Varroa Varroa product will be next on the regulatory review list, following the CPB product review.
Faster on the market
Singleton remembers when obtaining the genome of a plant or animal was an expensive chore. Today, genome information is readily available for a wide range of crop pests and diseases. The key is to identify the RNA mechanism that will work against the pest.
He adds that identifying the right RNA tool means finding the one that works on the target but has no impact on non-target pests, like beneficial insects.
While insects and disease are a key target for RNA, there are other potential uses for the technology, but it will take time. Singleton notes that the targeted nature of this technology has been positively received by regulators. “We’re not just a CPB company – crossing our fingers the EPA will give us its approval early next year.… The speed at which we can go from an idea to a product that works is very, very fast, ”he said. said. “We are treated like organic, [EPA] classified RNA as a biomolecule, and it is a food product. “
He explains that the behavior of the product – it disappears in the environment and leaves no residue in the soil or water – makes the regulator’s job very easy.