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Title: Plant “helper” immune receptors are Ca 2+ -permeable nonselective cation channels
Plant nucleotide-binding leucine-rich repeat receptors (NLRs) regulate immunity and cell death. InArabidopsis, a subfamily of “helper” NLRs is required by many “sensor” NLRs. Active NRG1.1 oligomerized, was enriched in plasma membrane puncta, and conferred cytoplasmic calcium ion (Ca2+) influx in plant and human cells. NRG1.1-dependent Ca2+influx and cell death were sensitive to Ca2+channel blockers and were suppressed by mutations affecting oligomerization or plasma membrane enrichment. Ca2+influx and cell death mediated by NRG1.1 and ACTIVATED DISEASE RESISTANCE 1 (ADR1), another helper NLR, required conserved negatively charged N-terminal residues. Whole-cell voltage-clamp recordings demonstrated thatArabidopsishelper NLRs form Ca2+-permeable cation channels to directly regulate cytoplasmic Ca2+levels and consequent cell death. Thus, helper NLRs transduce cell death signals directly.  more » « less
Award ID(s):
1758400
PAR ID:
10279138
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
American Association for the Advancement of Science (AAAS)
Date Published:
Journal Name:
Science
Volume:
373
Issue:
6553
ISSN:
0036-8075
Page Range / eLocation ID:
p. 420-425
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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