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Updated: May 14, 2026

Examining BCL-2 Family Function with Large Unilamellar Vesicles
08:35

Examining BCL-2 Family Function with Large Unilamellar Vesicles

Published on: October 5, 2012

Intracellular localization of the BCL-2 family member BOK and functional implications

N Echeverry1, D Bachmann, F Ke

  • 1Institute of Pharmacology, University of Bern, Bern, Switzerland.

Cell Death and Differentiation
|February 23, 2013
PubMed

Insights

The pro-apoptotic protein BOK, a BCL-2 family member, activates mitochondrial apoptosis in a BAX/BAK-dependent manner. BOK localizes to the Golgi and ER, suggesting these organelles are key sites for its tumor suppressor functions.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Cancer Research

Background:

  • BOK is a pro-apoptotic BCL-2 family member.
  • BOK resembles BAX and BAK in amino acid sequence.
  • BOK is hypothesized to be a tumor suppressor due to frequent genomic deletions in cancer.

Purpose of the Study:

  • To investigate the molecular functions of BOK.
  • To determine the localization and role of BOK in apoptosis.
  • To elucidate the relationship between BOK, BAX, and BAK in cell death.

Main Methods:

  • Enforced expression of BOK in cells with varying BAX/BAK status.
  • Analysis of BOK localization using microscopy.
  • Assessment of cell viability and organelle integrity upon BOK overexpression.
  • Evaluation of BOK-deficient cell response to Golgi/ER stress.

Main Results:

  • Enforced BOK expression activates the intrinsic apoptotic pathway in BAX/BAK-proficient cells.
  • BOK fails to induce apoptosis in cells lacking BAX and BAK.
  • BOK localizes to and inserts into Golgi and ER membranes via its C-terminal transmembrane domain.
  • BOK overexpression leads to early fragmentation of Golgi and ER compartments.
  • Bok-deficient cells exhibit abnormal responses to brefeldin A, a Golgi/ER stressor.

Conclusions:

  • BOK induces apoptosis in a BAX/BAK-dependent manner.
  • Major functions of BOK are associated with the Golgi and ER membranes.
  • BOK likely acts as a tumor suppressor through its functions at the Golgi and ER.

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