Phosphorylation stoichiometries of human eukaryotic initiation factors

Int J Mol Sci. 2014 Jun 27;15(7):11523-38. doi: 10.3390/ijms150711523.

Abstract

Eukaryotic translation initiation factors are the principal molecular effectors regulating the process converting nucleic acid to functional protein. Commonly referred to as eIFs (eukaryotic initiation factors), this suite of proteins is comprised of at least 25 individual subunits that function in a coordinated, regulated, manner during mRNA translation. Multiple facets of eIF regulation have yet to be elucidated; however, many of the necessary protein factors are phosphorylated. Herein, we have isolated, identified and quantified phosphosites from eIF2, eIF3, and eIF4G generated from log phase grown HeLa cell lysates. Our investigation is the first study to globally quantify eIF phosphosites and illustrates differences in abundance of phosphorylation between the residues of each factor. Thus, identification of those phosphosites that exhibit either high or low levels of phosphorylation under log phase growing conditions may aid researchers to concentrate their investigative efforts to specific phosphosites that potentially harbor important regulatory mechanisms germane to mRNA translation.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Eukaryotic Initiation Factors / metabolism*
  • HeLa Cells
  • Humans
  • Phosphorylation
  • Protein Processing, Post-Translational*

Substances

  • Eukaryotic Initiation Factors