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Updated: Jun 2, 2026

Monitoring eIF4F Assembly by Measuring eIF4E-eIF4G Interaction in Live Cells
08:47

Monitoring eIF4F Assembly by Measuring eIF4E-eIF4G Interaction in Live Cells

Published on: May 1, 2020

Phosphorylation of eukaryotic translation initiation factor 4G1 (eIF4G1) by protein kinase C{alpha} regulates eIF4G1

Mikhail Dobrikov1, Elena Dobrikova, Mayya Shveygert

  • 1Division of Neurosurgery, Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, USA.

Molecular and Cellular Biology
|May 18, 2011
PubMed

Insights

Mitogen-activated protein kinase (MAPK) signaling regulates protein synthesis by modifying translation factors. This study reveals that protein kinase C alpha (PKCα) phosphorylates eukaryotic translation initiation factor 4 gamma 1 (eIF4G1), impacting translation control.

Area of Science:

  • Molecular Biology
  • Cell Signaling
  • Cancer Research

Background:

  • Mitogen-activated protein kinases (MAPKs) regulate cell growth and proliferation via translation control.
  • Phosphorylation of translation initiation factors, like eukaryotic translation initiation factor 4E (eIF4E) by MAPK-activated Mnk1, is linked to cancer.
  • The impact of MAPK signaling on the translation apparatus, particularly eukaryotic translation initiation factor 4 gamma 1 (eIF4G1), remains unclear.

Purpose of the Study:

  • To investigate the effects of signal transduction on eIF4G1 and its role in translation control.
  • To elucidate the specific signaling pathways and kinases involved in eIF4G1 posttranslational modification.

Main Methods:

  • Utilized phorbol esters for specific activation of protein kinase C (PKC)-Ras-Erk signaling.
  • Employed phospho-proteomic analysis to identify phosphorylation sites on eIF4G1.
  • Conducted mutational analyses to confirm the role of specific phosphorylation sites.

Main Results:

  • Identified Ser1186 on eIF4G1 as a substrate for PKCα.
  • Demonstrated that PKCα activation triggers a cascade of phosphorylation events on eIF4G1.
  • Showed that these modifications may alter eIF4G1 structure and its interaction with Mnk1.

Conclusions:

  • PKCα-mediated phosphorylation of eIF4G1 is a key regulatory event in MAPK signaling pathways.
  • This phosphorylation cascade potentially modulates the translation initiation complex and protein synthesis.
  • Findings provide new insights into the intricate regulation of translation during mitogenic signaling and malignant transformation.

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