Biotech Updates

Scientists Show How Bacterial Protein in Aphid Saliva Triggers Plant Defense

June 11, 2014

A research team led by University of California Riverside (UCR) discovered a protein, GroEL, from the bacteria in aphids' body cavity that induces immune responses in plants. Aphids are devastating insect pests and harbor in their body cavity bacteria which are important to their reproduction and survival. The bacterium, Buchnera, cannot exist outside of the aphid. This mutually beneficial relationship is sabotaged, however, by a bacterium found in the aphid saliva, which likely alerts the plant about the aphid's presence.

Isgouhi Kaloshian, nematology professor and leader of the research project, said, "It seems that the plant immune system target the bacterium and exploits the strict mutual dependency between the plant and aphid to recognize the aphid as the intruder." According to Kaloshian, GroEL was known previously to trigger immunity in animals, but their finding that it induces immunity in plants is new. He added that GroEL can be exploited to engineer crops with durable resistance to aphids.

For more information about this research, read the UCR news release at