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Updated: Nov 13, 2025

Author Spotlight: Integrating BRET-Based Assays and Rare Mutation Analysis to Decipher RAF Kinase Regulation in Live Cells
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B-Raf autoinhibition in the presence and absence of 14-3-3

Mingzhen Zhang1, Hyunbum Jang1, Zhigang Li2

  • 1Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer ImmunoMetabolism, National Cancer Institute, Frederick, MD 21702, USA.

Structure (London, England : 1993)
|March 12, 2021
PubMed

Insights

B-Raf protein remains inactive through autoinhibition. Molecular dynamics simulations reveal how the 14-3-3 dimer influences B-Raf

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Cancer Research

Background:

  • B-Raf mutations are common drivers in various cancers.
  • B-Raf protein exists in an autoinhibited state via interactions between its domains and the 14-3-3 dimer.

Purpose of the Study:

  • To investigate the molecular mechanisms of B-Raf autoinhibition using computational simulations.
  • To explore the role of the 14-3-3 dimer in regulating B-Raf activity.

Main Methods:

  • Comprehensive molecular dynamics simulations were employed.
  • Two autoinhibition scenarios were analyzed: with and without the 14-3-3 dimer.

Main Results:

  • The 14-3-3 dimer stabilizes B-Raf autoinhibition by preventing kinase domain dimerization.
  • In the absence of 14-3-3, B-Raf's Ras-binding and cysteine-rich domains can obstruct kinase domain dimerization.
  • Simulations suggest a B-Raf activation mechanism involving contributions from both 14-3-3-bound and 14-3-3-free B-Raf kinase domains.

Conclusions:

  • B-Raf autoinhibition is regulated by domain interactions and the presence of the 14-3-3 dimer.
  • These findings elucidate a potential mechanism for B-Raf activation, leading to homo- and heterodimer formation.
  • Understanding these mechanisms could inform targeted cancer therapies.
Keywords:
B-Raf activationB-Raf autoinhibitionK-RasMAPK pathwayRaf dimerization

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