Plant “helper” immune receptors are Ca 2+ -permeable nonselective cation channels

Calcium signaling for host cell death In response to microbial pathogens, some plants kill off their own cells to limit further spread of infection. The Toll/Interleukin-1 receptor/Resistance class of nucleotide-binding leucine-rich repeat receptors (known as TNLs) function in plants as immune receptors. These TNLs work together with a dedicated set of helper proteins. Jacob et al. reveal the structure of one of these helpers known as NRG1 (N REQUIREMENT GENE 1). The structure resembles a known animal cation channel. The authors demonstrate that helper NLRs directly control calcium ion influx to initiate host cell death, providing a mechanism for TNL outputs. Science , abg7917, this issue p. 420