Team nebulizes aphids to knock down gene expression

Researchers are nebulizing soybean aphids with RNA, which, when incorporated into the body, can hinder the expression of specific genes. The new method of delivering "interfering RNA" in a mist will likely speed the process of discovering the function of many mystery genes in insects, the researchers report in the journal Insect Molecular Biology. 

Getting RNA into an aphid's body is no easy task. Common techniques involve injecting the RNA, or engineering a plant in the laboratory to produce the RNA in its tissues and getting the insect to feed on it. In the latter case, the RNA is often degraded in the insect's gut, minimizing its effectiveness.

Both methods are tedious, expensive and inefficient. As a result, the process of gene discovery in many sap-sucking insects like aphids has slowed to a crawl, Hansen said.

"We have all this genomic data we don't know what to do with," she said. "People are just desperate to get something that will work."

"By aerosolizing the RNA, we can deliver it directly to the target tissues," Thairu said. The researchers nebulized the aphids with tiny droplets of RNA bound to nanoparticles.

Nebulizing soybean aphids with RNA bound to nanoparticles appeared to block the function of a specific targeted gene, known as "bcat," the researchers found. Adult insects exposed to the RNA for bcat were significantly smaller than their unexposed peers and smaller than insects exposed only to the nanoparticles, the researchers found.