Glucose and amino acids modulate translation factor activation by growth factors in PC12 cells

Miranda Kleijn, Christopher G. Proud

Research output: Contribution to journalArticlepeer-review

33 Citations (Scopus)

Abstract

In PC12 phaeochromocytoma cells, protein synthesis is activated by epidermal and nerve growth factors (EGF and NGF). EGF and NGF also regulate a number of components of the translational machinery in these cells. Here we show that the ability of EGF and NGF to induce the phosphorylation of the 70 kDa ribosomal protein, S6 kinase, and the eukaryotic initiation factor (eIF), 4E-binding protein I, is dependent upon the presence of amino acids (but not glucose) in the medium. This resembles the regulation of these proteins by insulin, which also requires amino acids. Glucose, but not amino acids. is required for the activation of eIF2B by EGF and NGF. In contrast, EGF and NGF can still activate protein synthesis in the absence of nutrients, suggesting that other regulatory events are important in this. In nutrient-deprived cells, an increase in the phosphorylation of eIF4E, and the assembly of the eIF4F complex by EGF and NGF, coincided with the activation of protein synthesis. In serum-starved cells, activation of protein synthesis, phosphorylation of eIF4E, and formation of the eIF4F complex, were blocked by inhibition of MEK, a component of the extracellular regulated kinase (ERK) signalling pathway. Thus the ERK pathway plays a key role in the regulation of protein synthesis in PC12 cells.

Original languageEnglish
Pages (from-to)399-406
Number of pages8
JournalBiochemical Journal
Volume347
Issue number2
DOIs
Publication statusPublished or Issued - 15 Apr 2000
Externally publishedYes

Keywords

  • Epidermal growth factor
  • Eukaryotic initiation factor
  • Nerve growth factor
  • Nutrients
  • Protein synthesis

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

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