734 / 2019-05-12 10:33:45

Differential regulation of TNL-mediated immune signaling by helper NLRs

Plant NLR immune receptors, TNL, CNL, helper NLR,

全体主题 > Plant Microbe Interactions & Microbiomes

Nucleotide-binding leucine-rich repeat domain proteins (NLRs) serve as immune receptors in both plants and animals to recognize pathogens and trigger defense. The Activated Disease Resistance 1 (ADR1) family of coiled-coil NLRs (CNLs) have evolved as helper NLRs that function downstream of TIR-type sensor NLRs (TNLs). Close paralogs of ADR1s form the N REQUIREMENT GENE 1 (NRG1) family in Arabidopsis. Using a reverse genetics approach, we uncovered that NRG1a and NRG1b also function redundantly downstream of TNLs. Interestingly, ADR1s and NRG1s serve in two distinct parallel pathways contributing to TNL-specific immunity. Different sensor TNLs use ADR1s and NRG1s differentially to transduce downstream defense signals, and synergistic effects were observed among ADR1s and NRG1s. Cellular and biochemical studies on these helper NLRs will further elucidate the exact mechanism on how these helpers mediate TNL-mediated immunity.