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Updated: Aug 15, 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

Proteins encoded by ras oncogenes stimulate or inhibit phosphorylation of specific mitochondrial membrane proteins

J M Backer, I B Weinstein

    Biochemical and Biophysical Research Communications
    |February 26, 1986
    PubMed

    Insights

    Purified p21 proteins from ras oncogenes significantly alter mitochondrial protein phosphorylation. These proteins enhance 36KD protein phosphorylation and inhibit 17KD protein phosphorylation, suggesting a role in cellular regulation.

    Area of Science:

    • Biochemistry
    • Molecular Biology
    • Oncology

    Background:

    • Ras oncogenes are implicated in various cancers.
    • Protein phosphorylation is a key cellular signaling mechanism.
    • Mitochondria play crucial roles in cellular energy production and signaling.

    Purpose of the Study:

    • To investigate the effects of purified p21 proteins on mitochondrial protein phosphorylation.
    • To elucidate the potential role of p21 proteins in regulating cellular processes via phosphorylation.

    Main Methods:

    • Purification of p21 proteins encoded by ras oncogenes using recombinant DNA technology in E. coli.
    • Incubation of purified p21 proteins with isolated rat liver mitochondria.
    • Analysis of protein phosphorylation patterns using SDS-PAGE and acid hydrolysis.

    Main Results:

    • p21 proteins markedly enhanced the phosphorylation of a 36KD mitochondrial protein.
    • p21 proteins inhibited the phosphorylation of a 17KD mitochondrial protein.
    • Phospho-residues on the 36KD protein were sensitive to mild acid hydrolysis, indicating phosphoamide bonds.

    Conclusions:

    • p21 proteins can directly modulate mitochondrial protein phosphorylation.
    • The observed alterations in phosphorylation suggest a potential regulatory role for p21 proteins in vivo.
    • These findings contribute to understanding the molecular mechanisms by which ras oncogenes may exert their effects.

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