Activation of the double-stranded RNA-dependent protein kinase PKR by small ubiquitin-like modifier (SUMO).
J Biol Chem
; 289(38): 26357-26367, 2014 Sep 19.
Article
em En
| MEDLINE
| ID: mdl-25074923
ABSTRACT
The dsRNA-dependent kinase PKR is an interferon-inducible protein with ability to phosphorylate the α subunit of the eukaryotic initiation factor (eIF)-2 complex, resulting in a shut-off of general translation, induction of apoptosis, and inhibition of virus replication. Here we analyzed the modification of PKR by the small ubiquitin-like modifiers SUMO1 and SUMO2 and evaluated the consequences of PKR SUMOylation. Our results indicate that PKR is modified by both SUMO1 and SUMO2, in vitro and in vivo. We identified lysine residues Lys-60, Lys-150, and Lys-440 as SUMOylation sites in PKR. We show that SUMO is required for efficient PKR-dsRNA binding, PKR dimerization, and eIF2α phosphorylation. Furthermore, we demonstrate that SUMO potentiates the inhibition of protein synthesis induced by PKR in response to dsRNA, whereas a PKR SUMOylation mutant is impaired in its ability to inhibit protein synthesis and shows reduced capability to control vesicular stomatitis virus replication and to induce apoptosis in response to vesicular stomatitis virus infection. In summary, our data demonstrate the important role of SUMO in processes mediated by the activation of PKR.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
EIF-2 Quinase
/
Proteína SUMO-1
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Sumoilação
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article