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MAP kinase and the activation of quiescent cells

J V Ruderman1

  • 1Department of Anatomy and Cellular Biology, Harvard Medical School, Boston, Massachusetts 02115.

Current Opinion in Cell Biology
|April 1, 1993
PubMed

Insights

Mitogens activate mitogen-activated protein (MAP) kinases through signaling pathways involving ras and raf. These pathways are crucial for cell cycle activation and can be studied using cell-free oocyte systems.

Area of Science:

  • Cellular signaling
  • Molecular biology
  • Biochemistry

Background:

  • Mitogens trigger cellular responses by activating signaling pathways.
  • Mitogen-activated protein (MAP) kinases are key mediators of these responses.
  • Signal transduction pathways are conserved across different cell types and states.

Purpose of the Study:

  • To elucidate the role of MAP kinases in mitogen-induced cell cycle activation.
  • To investigate the signaling cascade from surface receptors to MAP kinase activation.
  • To highlight the utility of cell-free oocyte systems for studying signal transduction.

Main Methods:

  • Analysis of mitogen-activated signaling complexes.
  • Identification of key kinases in the signaling cascade (ras, raf, MAP kinase kinase, MAP kinase).
  • Utilizing cell-free systems derived from quiescent oocytes.

Main Results:

  • Mitogens rapidly activate MAP kinases via ras and raf.
  • Raf acts as a MAP kinase kinase kinase, initiating a cascade.
  • MAP kinase targets include kinases, transcription factors, and cell cycle regulators.
  • Similar signaling mechanisms are employed by G0-arrested somatic cells and G2-arrested oocytes.

Conclusions:

  • The ras-raf-MAP kinase cascade is a central pathway for mitogen signaling and cell cycle progression.
  • Cell-free oocyte systems provide a valuable platform for in vitro signal transduction research.
  • Understanding these pathways is essential for comprehending cell cycle control and activation.

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