1. Academic Validation
  2. A role for the eIF4E-binding protein 4E-T in P-body formation and mRNA decay

A role for the eIF4E-binding protein 4E-T in P-body formation and mRNA decay

  • J Cell Biol. 2005 Sep 12;170(6):913-24. doi: 10.1083/jcb.200504039.
Maria A Ferraiuolo 1 Sanjukta Basak Josee Dostie Elizabeth L Murray Daniel R Schoenberg Nahum Sonenberg
Affiliations

Affiliation

  • 1 Department of Biochemistry, McGill University, Montréal, Québec H3G 1Y6, Canada.
Abstract

4E-transporter (4E-T) is one of several proteins that bind the mRNA 5'cap-binding protein, eukaryotic initiation factor 4E (eIF4E), through a conserved binding motif. We previously showed that 4E-T is a nucleocytoplasmic shuttling protein, which mediates the import of eIF4E into the nucleus. At steady state, 4E-T is predominantly cytoplasmic and is concentrated in bodies that conspicuously resemble the recently described processing bodies (P-bodies), which are believed to be sites of mRNA decay. In this paper, we demonstrate that 4E-T colocalizes with mRNA decapping factors in bona fide P-bodies. Moreover, 4E-T controls mRNA half-life, because its depletion from cells using short interfering RNA increases mRNA stability. The 4E-T binding partner, eIF4E, also is localized in P-bodies. 4E-T interaction with eIF4E represses translation, which is believed to be a prerequisite for targeting of mRNAs to P-bodies. Collectively, these data suggest that 4E-T interaction with eIF4E is a priming event in inducing messenger ribonucleoprotein rearrangement and transition from translation to decay.

Figures