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Examining BCL-2 Family Function with Large Unilamellar Vesicles
Published on: October 5, 2012
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Bok: real killer or bystander with non-apoptotic roles?
Caden G Bonzerato1, Richard J H Wojcikiewicz1
1Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY, United States.
Frontiers in Cell and Developmental Biology
|May 1, 2023
Summary
The Bcl-2-related ovarian killer (Bok) protein functions differently than previously thought. Endogenous Bok acts as an endoplasmic reticulum bystander, regulating cellular processes rather than directly causing cell death.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- The Bcl-2-related ovarian killer (Bok) protein was initially classified as pro-apoptotic.
- Over-expression studies suggested Bok induces cell death, leading to its
- labeling as a killer protein.
- However, Bok's widespread expression and differing effects of endogenous versus over-expressed forms raise questions about this classification.
Purpose of the Study:
- To re-evaluate the role of Bok in apoptosis.
- To differentiate the functions of endogenous Bok from over-expressed Bok.
- To propose a revised understanding of Bok's cellular localization and function.
Main Methods:
- Review of existing literature on Bok expression and function.
- Comparative analysis of over-expressed Bok versus endogenous Bok.
- Examination of Bok's interactions and localization within the cell.
Main Results:
- Endogenous Bok differs significantly from pro-apoptotic mediators Bak and Bax.
- Bok is a stable protein located in the endoplasmic reticulum, bound to inositol 1,4,5 trisphosphate receptors.
- Bok regulates endoplasmic reticulum/mitochondria contact sites and mitochondrial dynamics.
Conclusions:
- The classification of Bok as a
- killer
- protein is misleading.
- Endogenous Bok functions as an endoplasmic reticulum-located bystander.
- Bok plays crucial non-apoptotic roles in cellular regulation.
Keywords:
Bcl-2 related ovarian killerapoptosisinositol 1 4 5-trisphosphate receptormitochondria-associated ER membranesmitochondrial dynamicsmyeloid-cell leukemia 1ubiquitin-proteasome pathwayMore Related Videos
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