Format

Send to

Choose Destination
EMBO J. 2006 Apr 19;25(8):1730-40. Epub 2006 Apr 6.

Antiviral effect of the mammalian translation initiation factor 2alpha kinase GCN2 against RNA viruses.

Author information

1
Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Facultad de Ciencias, Cantoblanco, Universidad Autónoma de Madrid, Madrid, Spain.

Abstract

In mammals, four different protein kinases, heme-regulated inhibitor, double-stranded RNA-dependent protein kinase (PKR), general control non-derepressible-2 (GCN2) and PKR-like endoplasmic reticulum kinase, regulate protein synthesis in response to environmental stresses by phosphorylating the alpha-subunit of the initiation factor 2 (eIF2alpha). We now report that mammalian GCN2 is specifically activated in vitro upon binding of two nonadjacent regions of the Sindbis virus (SV) genomic RNA to its histidyl-tRNA synthetase-related domain. Moreover, endogenous GCN2 is activated in cells upon SV infection. Strikingly, fibroblasts derived from GCN2-/- mice possess an increased permissiveness to SV or vesicular stomatitis virus infection. We further show that mice lacking GCN2 are extremely susceptible to intranasal SV infection, demonstrating high virus titers in the brain compared to similarly infected control animals. The overexpression of wild-type GCN2, but not the catalytically inactive GCN2-K618R variant, in NIH 3T3 cells impaired the replication of a number of RNA viruses. We determined that GCN2 inhibits SV replication by blocking early viral translation of genomic SV RNA. These findings point to a hitherto unrecognized role of GCN2 as an early mediator in the cellular response to RNA viruses.

PMID:
16601681
PMCID:
PMC1440839
DOI:
10.1038/sj.emboj.7601073
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Wiley Icon for PubMed Central
Loading ...
Support Center