Genome‐wide functional analysis of hot pepper immune receptors reveals an autonomous NLR clade in seed plants

Summary Plants possess hundreds of intracellular immune receptors encoding nucleotide‐binding domain leucine‐rich repeat (NLR) proteins. Full‐length NLRs or a specific domain of NLRs often induce plant cell death in the absence of pathogen infection. In this study we used genome‐wide transient expre...

Full description

Saved in:
Bibliographic Details
Published in:The New phytologist 2021-01, Vol.229 (1), p.532-547
Main Authors: Lee, Hye‐Young, Mang, Hyunggon, Choi, Eunhye, Seo, Ye‐Eun, Kim, Myung‐Shin, Oh, Soohyun, Kim, Saet‐Byul, Choi, Doil
Format: Article
Language:English
Subjects:
Apoptosis
Capsicum - genetics
Capsicum annuum
Cell death
coiled‐coil domain
Coils
Functional analysis
Gene expression
Genomes
Leucine
Mortality
Mutagenesis
NLR Proteins - genetics
Nucleotide sequence
Nucleotides
Pathogens
Peppers
Phylogeny
Plant Diseases - genetics
Plant Immunity - genetics
plant NLR
Plant Proteins - genetics
Receptors
Seeds - genetics
singleton NLR
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Summary Plants possess hundreds of intracellular immune receptors encoding nucleotide‐binding domain leucine‐rich repeat (NLR) proteins. Full‐length NLRs or a specific domain of NLRs often induce plant cell death in the absence of pathogen infection. In this study we used genome‐wide transient expression analysis to identify a group of NLRs (ANLs; ancient and autonomous NLRs) carrying autoactive coiled‐coil (CCA) domains in pepper (Capsicum annuum). CCA‐mediated cell death mimics hypersensitive cell death triggered by the interaction between NLRs and pathogen effectors. Sequence alignment and mutagenesis analyses revealed that the intact α1 helix of CCAs is critical for both CCA‐ and ANL‐mediated cell death. Cell death induced by CCAs does not require NRG1/ADR1 or NRC type helper NLRs, suggesting ANLs may function as singleton NLRs. We also found that CCAs localize to the plasma membrane, as demonstrated for Arabidopsis singleton NLR ZAR1. Extended studies revealed that autoactive CCAs are well conserved in other Solanaceae plants as well as in rice, a monocot plant. Further phylogenetic analyses revealed that ANLs are present in all tested seed plants (spermatophytes). Our study not only uncovers the autonomous NLR clade in plants but also provides powerful resources for dissecting the underlying molecular mechanism of NLR‐mediated cell death in plants.
ISSN:0028-646X
1469-8137
DOI:10.1111/nph.16878