The eIF3 Interactome Reveals the Translasome, a Supercomplex Linking Protein Synthesis and Degradation Machineries Academic Article


  • Molecular Cell


  • eIF3 promotes translation initiation, but relatively little is known about its full range of activities in the cell. Here, we employed affinity purification and highly sensitive LC-MS/MS to decipher the fission yeast eIF3 interactome, which was found to contain 230 proteins. eIF3 assembles into a large supercomplex, the translasome, which contains elongation factors, tRNA synthetases, 40S and 60S ribosomal proteins, chaperones, and the proteasome. eIF3 also associates with ribosome biogenesis factors and the importins-B Kap123p and Sal3p. Our genetic data indicated that the binding to both importins-B is essential for cell growth, and photobleaching experiments revealed a critical role for Sal3p in the nuclear import of one of the translasome constituents, the proteasome. Our data reveal the breadth of the eIF3 interactome and suggest that factors involved in translation initiation, ribosome biogenesis, translation elongation, quality control, and transport are physically linked to facilitate efficient protein synthesis.

publication date

  • 2009-10-9


  • 36


  • Amino Acyl-tRNA Synthetases
  • Cell Nucleus Active Transport
  • Growth
  • Karyopherins
  • Peptide Elongation Factors
  • Photobleaching
  • Proteasome Endopeptidase Complex
  • Proteins
  • Proteolysis
  • Quality Control
  • Ribosomal Proteins
  • Ribosomes
  • Schizosaccharomyces

International Standard Serial Number (ISSN)

  • 1097-2765

number of pages

  • 12

start page

  • 141

end page

  • 152