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Analysis of Translation Initiation During Stress Conditions by Polysome Profiling
Published on: May 19, 2014
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Translational control in stress and apoptosis
Martin Holcik1, Nahum Sonenberg
1Apoptosis Research Center, Room R3116, Children's Hospital of Eastern Ontario, 401 Smyth Road, Ottawa, ON, K1H 8L1, Canada. martin@mgcheo.med.uottawa.ca
Nature Reviews. Molecular Cell Biology
|April 2, 2005
Summary
Cells rapidly adjust protein production during stress using translational control. This summary explores how regulating translation, via eukaryotic initiation factor-2alpha and internal ribosome entry sites, impacts cellular stress responses and apoptosis.
Area of Science:
- Molecular Biology
- Cellular Biology
- Biochemistry
Background:
- Cells employ sophisticated mechanisms to adapt to environmental stress.
- Gene expression regulation is crucial for cellular survival and function.
- Translation control offers a rapid and selective method for modulating protein levels during stress.
Purpose of the Study:
- To examine the role of translational control in the cellular stress response.
- To illustrate the importance of translational regulation in apoptosis.
- To analyze two key models of translational control: eukaryotic initiation factor-2alpha phosphorylation and internal ribosome entry site-mediated translation.
Main Methods:
- Review of existing literature on translational control mechanisms.
- Analysis of two specific models: eukaryotic initiation factor-2alpha (eIF2α) phosphorylation and internal ribosome entry site (IRES) mediated translation.
- Examination of the impact of these mechanisms on cellular stress response and apoptosis.
Main Results:
- Translational control provides immediate and selective changes in protein synthesis during stress.
- Phosphorylation of eukaryotic initiation factor-2alpha (eIF2α) is a critical regulatory point.
- Internal ribosome entry sites (IRES) facilitate cap-independent translation initiation, crucial under stress conditions.
Conclusions:
- Translational control is a vital component of the cellular stress response.
- The studied models highlight the significance of regulating protein synthesis for cell survival and programmed cell death (apoptosis).
- Understanding these mechanisms offers insights into cellular adaptation and disease pathways.
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