Bacteria and immune mechanisms in plants reportedly use the TIR (Toll/interleukin-1 receptor) to sustain themselves, according to a new study from the Weizmann Institute of Science.
The study, published in the Nature journal on Wednesday, confirms that both bacteria, as well as immune mechanism origins in plants, use TIR and that it achieves immunity in plants and bacteria in similar ways using signal molecules. Its immune response keeps viruses and bacteria from spreading when the plant is infected.
Led by Prof. Rotem Sorek of Weizmann’s Molecular Genetics Department, the study also elaborates that the new information may help people strengthen the defenses of plants in order to prevent billions of dollars in crop losses throughout the planet, and may be useful for researchers trying to find new ways to enhance plants' immune systems and bolster their ability to resist infections.
American and Australian scientists already discovered two years ago that a plant’s immune system kills infected cells using TIR.
Bacteria fight against phages, a type of virus. Dr. Gal Ofir, Sorek's colleague who also led the study at Weizmann, found that the TIR can sense the phages' invasion of a bacterium and generates a signal that alerts a second protein, which destroys the molecule that is critical to bacterial metabolism. Therefore, the bacterium dies before the phage multiplies.
“Our findings have established a direct evolutionary link between the immunity of plants and that of bacteria,” Sorek says. “Moreover, they provide a basis for investigating how a major defense system, one involving TIR, works in plants.”