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Updated: Aug 20, 2026

Characterize Disease-related Mutants of RAF Family Kinases by Using a Set of Practical and Feasible Methods
07:49

Characterize Disease-related Mutants of RAF Family Kinases by Using a Set of Practical and Feasible Methods

Published on: July 17, 2019

Novel C-Raf phosphorylation sites: serine 296 and 301 participate in Raf regulation

Mirko Hekman1, Andreas Fischer, Lawrence P Wennogle

  • 1Institut fuer Medizinische Strahlenkunde und Zellforschung, University of Wuerzburg, 97078 Wuerzburg, Germany.

FEBS Letters
|January 12, 2005
PubMed

Insights

Researchers identified novel phosphorylation sites on C-Raf kinase, specifically serine 296 and 301. These sites regulate C-Raf activity, offering new insights into kinase signaling pathways.

Area of Science:

  • Molecular Biology
  • Cell Signaling
  • Biochemistry

Background:

  • C-Raf kinase is a key regulator in cellular signaling pathways.
  • Its activity is modulated by complex phosphorylation events.
  • Understanding C-Raf phosphorylation is crucial for deciphering cell growth and differentiation.

Purpose of the Study:

  • To identify and quantify prominent phosphorylation sites on C-Raf.
  • To investigate the role of novel phosphorylation sites in C-Raf regulation.
  • To elucidate the contribution of specific serine residues to C-Raf's negative regulation.

Main Methods:

  • Mass spectrometry analysis of wild-type and mutant C-Raf.
  • Analysis of C-Raf-Y340D/Y341D constitutively active mutant.
  • Site-directed mutagenesis (serine to alanine/aspartic acid substitutions).

Main Results:

  • Confirmed known C-Raf phosphorylation sites, except for T268/T269 and T491/S494.
  • Identified novel phosphorylation sites at serine 296 and serine 301.
  • Phosphorylation degree at S296 and S301 correlates with C-Raf activation levels.
  • Mutational analysis demonstrated S296 and S301 contribute to negative C-Raf regulation.

Conclusions:

  • Serine 296 and serine 301 are novel, functionally significant phosphorylation sites on C-Raf.
  • These sites play a role in the negative regulation of C-Raf kinase activity.
  • Findings provide a deeper understanding of C-Raf kinase signaling and its modulation.

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