Overexpression of eukaryotic translation elongation factor 3 impairs Gcn2 protein activation

Abstract

Background: The eIF2α kinase Gcn2 aids cells to overcome amino acid starvation. For sensing starvation, Gcn2 must bind Gcn1, and both must contact the ribosome. Results: Overexpression of translation elongation factor eEF3 inhibits Gcn1-mediated Gcn2 activation. Conclusion: eEF3 keeps Gcn2 in its latent state under nutrient replete conditions. Significance: We discovered a novel unanticipated role of a general translation factor in controlling Gcn2. © 2012 by The American Society for Biochemistry and Molecular Biology, Inc.