UC Berkeley researchers published a study today in Nature that reports the discovery of a calcium channel that activates a plant’s immune system during pathogen attack. Pathogen-associated molecular patterns (PAMPs) activate innate immunity in both animals and plants, with calcium being a well-known signal for triggering defense responses. However, the mechanism for this calcium-induced signaling is largely unknown.
In the paper, Sheng Luan, a professor in the Department of Plant and Microbial Biology, and colleagues find that calcium is essential for the activation of the innate immune response in plants, through the function of two genes encoding channel proteins, CNGC2 and CNGC4. These two channel proteins assemble into a functional calcium gateway, triggering an increase in internal calcium levels. The elevated calcium levels then go on to initiate calcium-dependent immunity programs in plants, defending plants against pathogen-induced diseases.