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Updated: Aug 7, 2026

Assessment of Mitochondrial Functions and Cell Viability in Renal Cells Overexpressing Protein Kinase C Isozymes
15:43

Assessment of Mitochondrial Functions and Cell Viability in Renal Cells Overexpressing Protein Kinase C Isozymes

Published on: January 7, 2013

Protein kinase-c activation inhibits tyrosine phosphorylation of the c-met protein

L Gandino1, M F Di Renzo, S Giordano

  • 1Department of Biomedical Sciences and Oncology, University of Torino, Italy.

Oncogene
|May 1, 1990
PubMed

Insights

Protein kinase C activation reduces tyrosine phosphorylation of the c-met receptor beta subunit in gastric carcinoma cells. This suggests protein kinase C negatively modulates the c-met proto-oncogene receptor activity.

Area of Science:

  • Molecular Biology
  • Cell Signaling
  • Oncogenesis

Background:

  • The c-met proto-oncogene encodes a tyrosine kinase receptor involved in cell growth and cancer.
  • The c-met receptor's beta subunit undergoes in vivo phosphorylation in gastric carcinoma cells.

Purpose of the Study:

  • To investigate the effect of protein kinase C (PKC) activators on the phosphorylation of the c-met receptor's beta subunit.
  • To determine if PKC modulates c-met receptor activity.

Main Methods:

  • Western blotting using phosphotyrosine antibodies on GTL-16 cells treated with PKC activators (TPA, PdBu, OAG).
  • Phospho-amino acid analysis of immunoprecipitated c-met protein from [32P]orthophosphate-labeled cells.

Main Results:

  • PKC activators significantly reduced tyrosine phosphorylation of the c-met beta subunit in a dose- and time-dependent manner.
  • Depletion of PKC increased tyrosine phosphorylation of the c-met beta subunit.
  • PKC activation increased serine phosphorylation while decreasing tyrosine phosphorylation of the c-met protein.

Conclusions:

  • Protein kinase C negatively modulates the c-met proto-oncogene receptor.
  • PKC-mediated phosphorylation of the c-met receptor may regulate its tyrosine kinase activity, similar to EGF and insulin receptors.

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