Calcium (Ca2+) signalling regulates salicylic acid (SA)‐mediated immune response through calmodulin‐meditated transcriptional activators, AtSRs/CAMTAs, but its mechanism is not fully understood. Here, we report an AtSR1/CAMTA3‐mediated regulatory mechanism involving the expression of the SA receptor, NPR1. Results indicate that the transcriptional expression of
Lactic acid bacteria produce a variety of antimicrobial peptides known as bacteriocins. Most bacteriocins are understood to kill sensitive bacteria through receptor‐mediated disruptions. Here, we report on the identification of the
- NSF-PAR ID:
- 10459734
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- MicrobiologyOpen
- Volume:
- 8
- Issue:
- 11
- ISSN:
- 2045-8827
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract NPR1 was regulated by AtSR1 binding to a CGCG box in theNPR1 promotor. Theatsr1 mutant exhibited resistance to the virulent strain ofPseudomonas syringae pv.tomato (Pst ), however, was susceptible to an avirulentPst strain carryingavrRpt2 , due to the failure of the induction of hypersensitive responses. These resistant/susceptible phenotypes in theatsr1 mutant were reversed in thenpr1 mutant background, suggesting that AtSR1 regulates NPR1 as a downstream target during plant immune response. The virulentPst strain triggered a transient elevation in intracellular Ca2+concentration, whereas the avirulentPst strain triggered a prolonged change. The distinct Ca2+signatures were decoded into the regulation of NPR1 expression through AtSR1's IQ motif binding with Ca2+‐free‐CaM2, while AtSR1's calmodulin‐binding domain with Ca2+‐bound‐CaM2. These observations reveal a role for AtSR1 as a Ca2+‐mediated transcription regulator in controlling the NPR1‐mediated plant immune response. -
Key points Dravet syndrome mice (
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AZD7325 demonstrates seizure protective effects in
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