Phosphorylation of the eukaryotic translation initiation factor 4E-transporter (4E-T) by c-Jun N-terminal kinase promotes stress-dependent P-body assembly.

ABSTRACT: Processing bodies (PBs, or P bodies) are cytoplasmic granules involved in mRNA storage and degradation that participate in the regulation of gene expression. PBs concentrate nontranslated mRNAs and several factors involved in mRNA decay and translational repression, including the eukaryotic translation initiation factor 4E-transporter (4E-T). 4E-T is required for PB assembly, but little is known about the molecular mechanisms that regulate its function. Here, we demonstrate that oxidative stress promotes multisite 4E-T phosphorylation. We show that the c-Jun N-terminal kinase (JNK) is targeted to PBs in response to oxidative stress and promotes the phosphorylation of 4E-T. Quantitative mass spectrometry analysis reveals that JNK phosphorylates 4E-T on six proline-directed sites that are re

SUBMITTER: Cargnello M 

PROVIDER: S-EPMC3486182 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature