Arabidopsis nonresponding to oxylipins locus NOXY7 encodes a yeast GCN1 homolog that mediates noncanonical translation regulation and stress adaptation.
Plant Cell Environ
; 41(6): 1438-1452, 2018 06.
Article
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| MEDLINE
| ID: mdl-29499090
ABSTRACT
Stress adaptation and translational regulation was studied using noxy7 (nonresponding to oxylipins7) from a series of Arabidopsis thaliana mutants. We identified the noxy7 mutation in At1g64790, which encodes a homolog of the yeast translational regulator General Control Nonderepressible1 (GCN1) that activates the GCN2 kinase; GCN2 in turn phosphorylates the α subunit of the translation initiation factor eIF2. This regulatory circuit is conserved in yeast and mammals, in which phosphorylated eIF2α (P-eIF2α) facilitates stress adaptation by inhibiting protein synthesis. In phenotypic and de novo protein synthesis studies with Arabidopsis mutants, we found that NOXY7/GCN1 and GCN2 mediate P-eIF2α formation and adaptation to amino acid deprivation; however, P-eIF2α formation is not linked to general protein synthesis arrest. Additional evidence suggested that NOXY7/GCN1 but not GCN2 regulates adaptation to mitochondrial dysfunction, high boron concentration, and activation of plant immunity to infection by Pseudomonas syringae pv tomato (Pst). In these responses, NOXY7/GCN1 acts with GCN20 to regulate translation in a noncanonical pathway independently of GCN2 and P-eIF2α. These results show the lesser functional relevance of GCN2 and P-eIF2α in plants relative to other eukaryotes and highlight the prominent role of NOXY7/GCN1 and GCN20 in regulation of translation and stress adaptation in plants.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Estrés Fisiológico
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Biosíntesis de Proteínas
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Adaptación Fisiológica
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Factores de Elongación de Péptidos
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Homología de Secuencia de Aminoácido
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Arabidopsis
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Proteínas de Saccharomyces cerevisiae
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Proteínas de Arabidopsis
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Péptidos y Proteínas de Señalización Intracelular
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Plant Cell Environ
Asunto de la revista:
BOTANICA
Año:
2018
Tipo del documento:
Article
País de afiliación:
España