By Susan Milius
Deadly, fat-sucking mites and wing-wrecking viruses, take note. Specially engineered gut microbes can defend honeybees by tricking their enemies into self-destruction.
Rod-shaped Snodgrassella bacteria, common in bee guts, were engineered to release double-stranded RNA molecules that dial down gene activity in a mite or virus. The pest then sabotages itself by shutting down some of its own vital genes. This strategy hijacks a natural biological process called RNA interference, or RNAi (SN: 10/4/06). The gut bacteria churning out this targeted disinformation work “something like a living vaccine,” says microbiologist Sean Leonard of the University of Texas at Austin.
The RNA’s targeted approach intrigues scientists interested in fighting pests or other problems while minimizing the chances of hurting innocent bystanders.
Earlier work shows that directly dosing bees with the customized RNA also can work, Leonard says, but the stuff is expensive to make and degrades rapidly. A gut microbe, however, can keep making the RNA, replenishing the supply.