کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4361454 | 1301388 | 2011 | 13 صفحه PDF | دانلود رایگان |
SummaryPlants and animals have evolved structurally related innate immune sensors, designated NLRs, to detect intracellular nonself molecules. NLRs are modular, consisting of N-terminal coiled-coil (CC) or TOLL/interleukin-1 receptor (TIR) domains, a central nucleotide-binding (NB) domain, and C-terminal leucine-rich repeats (LRRs). The polymorphic barley mildew A (MLA) locus encodes CC-containing allelic immune receptors recognizing effectors of the pathogenic powdery mildew fungus. We report the crystal structure of an MLA receptor's invariant CC domain, which reveals a rod-shaped homodimer. MLA receptors also self-associate in vivo, but self-association appears to be independent of effector-triggered receptor activation. MLA CC mutants that fail to self-interact impair in planta cell death activity triggered by the CC domain alone and by an autoactive full-length MLA receptor that mimics its ATP-bound state. Thus, CC domain-dependent dimerization of the immune sensor defines a minimal functional unit and implies a role for the dimeric CC module in downstream immune signaling.
► Crystal structure of coiled-coil module of barley MLA immune receptor resolved
► MLA self-associates in vivo independent of pathogen trigger
► CC-dependent receptor self-association is required for immunity and cell death
Journal: - Volume 9, Issue 3, 17 March 2011, Pages 187–199