Some nucleotideâbinding and leucineârich repeat receptors (NLRs) indirectly detect pathogen effectors by monitoring their host targets. In We identified that the We demonstrated that recognition of the The recognition of sequenceâunrelated effectors by NbPtr1 and NbZAR1 provides an additional example of convergently evolved effector recognition. Identification of key components involved in Ptr1 and ZAR1âmediated immunity could reveal unique mechanisms of expanded effector recognition.
Activation of nucleotideâbinding leucineârich repeat receptors (NLRs) results in immunity and a localized cell death. NLR cell death activity requires oligomerization and in some cases plasma membrane (PM) localization. The exact mechanisms underlying PM localization of NLRs lacking predicted transmembrane domains or recognizable lipidation motifs remain elusive. We used confocal microscopy, genetically encoded molecular tools and proteinâlipid overlay assays to determine whether PM localization of members of the Arabidopsis HeLoâ/RPW8âlike domain âhelperâ NLR (RNL) family is mediated by the interaction with negatively charged phospholipids of the PM. Our results show that PM localization and stability of some RNLs and one CCâtype NLRÂ (CNL) depend on the direct interaction with PM phospholipids. Depletion of phosphatidylinositolâ4âphosphate from the PM led to a misâlocalization of the analysed NLRs and consequently inhibited their cell death activity. We further demonstrate homoâ and heteroâassociation of members of the RNL family. Our results provide new insights into the molecular mechanism of NLR localization and defines an important role of phospholipids for CNL and RNL PM localization and consequently, for their function. We propose that RNLs interact with anionic PM phospholipids and that RNLâmediated cell death and immune responses happen at the PM.
- Award ID(s):
- 1758400
- NSF-PAR ID:
- 10447026
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 232
- Issue:
- 6
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 2440-2456
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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