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

Published on: January 7, 2013

Protein kinase C involvement in apoptosis

M Lucas1, V Sánchez-Margalet

  • 1Departamento de Bioquímica Médica y Biología Molecular, Hospital Universitario Virgen Macarena, Facultad de Medicina, Sevilla, Spain.

General Pharmacology
|September 1, 1995
PubMed

Insights

Protein kinase C (PKC) involvement in apoptosis varies greatly. Its inhibition of calcium entry and interactions with sphingomyelin pathways suggest complex roles in programmed cell death and mitotic catastrophe.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • The role of Protein Kinase C (PKC) in apoptosis is complex and context-dependent, with conflicting observations across different cell types and conditions.
  • Apoptosis, or programmed cell death, can be triggered by various cellular stresses and involves intricate signaling pathways.
  • Oncogenic proteins like bcl-2 and signaling molecules such as ceramide and sphingosine are implicated in regulating cell death.

Purpose of the Study:

  • To elucidate the variable involvement of PKC in apoptosis.
  • To investigate the mechanisms by which PKC influences calcium-dependent enzymes and the sphingomyelin pathway in apoptosis.
  • To explore the role of p34cdc2 and its regulation in the context of apoptosis and mitotic catastrophe.

Main Methods:

  • Review and synthesis of existing literature on PKC, apoptosis, and related signaling pathways.
  • Analysis of studies investigating the effects of PKC inhibition on calcium signaling.
  • Examination of research on ceramide, sphingosine, and their impact on apoptotic pathways.
  • Investigation of the regulation of p34cdc2 by kinases and phosphatases and its relation to DNA replication.

Main Results:

  • PKC's role in apoptosis is highly variable, influenced by cell type, apoptotic stimuli, cell cycle phase, and intracellular signaling.
  • PKC inhibition of store-operated calcium entry, sensitive to bcl-2, is proposed to block calcium-dependent enzymes crucial for apoptosis.
  • The sphingomyelin pathway to apoptosis involves ceramide-activated phosphatases and PKC inhibition by sphingosine.
  • p34cdc2 is identified as a potential target protein, with its dysregulated activation relative to DNA replication leading to mitotic catastrophe, which shares features with apoptosis.

Conclusions:

  • PKC plays a multifaceted role in apoptosis, necessitating further research to understand its precise mechanisms.
  • Calcium signaling and the sphingomyelin pathway are key mediators in PKC-dependent and independent apoptotic processes.
  • The regulation of p34cdc2 is critical for preventing mitotic catastrophe and maintaining cellular integrity, highlighting its connection to apoptosis.

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