CALCIUM-DEPENDENT PROTEIN KINASE5 Associates with the Truncated NLR Protein TIR-NBS2 to Contribute to exo70B1-Mediated Immunity.
Plant Cell
; 29(4): 746-759, 2017 Apr.
Article
em En
| MEDLINE
| ID: mdl-28351987
ABSTRACT
Calcium-dependent protein kinases (CPKs) function as calcium sensors and play important roles in plant immunity. Loss of function of the exocyst complex subunit EXO70B1 leads to autoimmunity caused by activation of TN2, a truncated Toll/interleukin-1 receptor-nucleotide binding sequence protein. Here we show, based on a screen for suppressors of exo70B1, that exo70B1-activated autoimmune responses require CPK5 However, the CPK5 homologs CPK4, CPK6, and CPK11, which were previously reported to function redundantly with CPK5 in effector-triggered immunity, did not contribute to exo70B1-associated phenotypes, indicating that CPK5 plays a unique role in plant immunity. Overexpressing CPK5 results in TN2-dependent autoimmunity and enhanced disease resistance, reminiscent of the exo70B1 phenotypes. Ectopic expression of CPK5 in the exo70B1 mutant led to constitutive CPK5 protein kinase activity, which was not detectable in tn2 mutants. Furthermore, TN2 interacts with the CPK5 N-terminal variable and kinase domains, stabilizing CPK5 kinase activity in vitro. This work uncovers a direct functional link between an atypical immune receptor and a crucial component of early immune signaling increased immunity in exo70B1 depends on TN2 and CPK5 and, in a positive feedback loop, TN2 keeps CPK5 enzymatically active beyond the initiating stimulus.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Quinases Dependentes de Cálcio-Calmodulina
/
Proteínas de Arabidopsis
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Proteínas de Transporte Vesicular
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Imunidade Vegetal
/
Resistência à Doença
Tipo de estudo:
Risk_factors_studies
Idioma:
En
Revista:
Plant Cell
Assunto da revista:
BOTANICA
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
China