Gene expression during acute and prolonged hypoxia is regulated by distinct mechanisms of translational control

Marianne Koritzinsky; Michaël G Magagnin; Twan van den Beucken; Renaud Seigneuric; Kim Savelkouls; Josée Dostie; Stéphane Pyronnet; Randal J Kaufman; Sherry A Weppler; Jan Willem Voncken; Philippe Lambin; Constantinos Koumenis; Nahum Sonenberg; Bradly G Wouters

doi:10.1038/sj.emboj.7600998

Gene expression during acute and prolonged hypoxia is regulated by distinct mechanisms of translational control

EMBO J. 2006 Mar 8;25(5):1114-25. doi: 10.1038/sj.emboj.7600998. Epub 2006 Feb 9.

Authors

Marianne Koritzinsky¹, Michaël G Magagnin, Twan van den Beucken, Renaud Seigneuric, Kim Savelkouls, Josée Dostie, Stéphane Pyronnet, Randal J Kaufman, Sherry A Weppler, Jan Willem Voncken, Philippe Lambin, Constantinos Koumenis, Nahum Sonenberg, Bradly G Wouters

Affiliation

¹ Department of Radiation Oncology (Maastro), GROW Research Institute, University of Maastricht, The Netherlands.

Abstract

Hypoxia has recently been shown to activate the endoplasmic reticulum kinase PERK, leading to phosphorylation of eIF2alpha and inhibition of mRNA translation initiation. Using a quantitative assay, we show that this inhibition exhibits a biphasic response mediated through two distinct pathways. The first occurs rapidly, reaching a maximum at 1-2 h and is due to phosphorylation of eIF2alpha. Continued hypoxic exposure activates a second, eIF2alpha-independent pathway that maintains repression of translation. This phase is characterized by disruption of eIF4F and sequestration of eIF4E by its inhibitor 4E-BP1 and transporter 4E-T. Quantitative RT-PCR analysis of polysomal RNA indicates that the translation efficiency of individual genes varies widely during hypoxia. Furthermore, the translation efficiency of individual genes is dynamic, changing dramatically during hypoxic exposure due to the initial phosphorylation and subsequent dephosphorylation of eIF2alpha. Together, our data indicate that acute and prolonged hypoxia regulates mRNA translation through distinct mechanisms, each with important contributions to hypoxic gene expression.

Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't

MeSH terms

Adaptor Proteins, Signal Transducing
Adenocarcinoma / metabolism
Adenocarcinoma / pathology
Animals
Carrier Proteins / metabolism
Cell Cycle Proteins
Endoplasmic Reticulum / metabolism
Eukaryotic Initiation Factor-2 / genetics
Eukaryotic Initiation Factor-2 / physiology*
Eukaryotic Initiation Factor-4E / metabolism
Eukaryotic Initiation Factor-4F / metabolism
Fibroblasts / metabolism
Gene Expression Regulation / physiology*
HeLa Cells
Humans
Hypoxia / genetics*
Lung Neoplasms / metabolism
Lung Neoplasms / pathology
Mice
Mice, Knockout
Nucleocytoplasmic Transport Proteins / metabolism
Phosphoproteins / metabolism
Phosphorylation
Polyribosomes / genetics
Protein Biosynthesis*
RNA / analysis*
RNA / genetics
Reverse Transcriptase Polymerase Chain Reaction
Transfection

Substances

Adaptor Proteins, Signal Transducing
Carrier Proteins
Cell Cycle Proteins
EIF4EBP1 protein, human
EIF4ENIF1 protein, human
Eukaryotic Initiation Factor-2
Eukaryotic Initiation Factor-4E
Eukaryotic Initiation Factor-4F
Nucleocytoplasmic Transport Proteins
Phosphoproteins
RNA

Grants and funding

R01 CA094214/CA/NCI NIH HHS/United States