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Stochasticity in gene expression: from theories to phenotypes
Mads Kaern1, Timothy C Elston, William J Blake
1Department of Cellular and Molecular Medicine and Ottawa Institute of Systems Biology, University of Ottawa, 451 Smyth Road, Ottawa, Ontario K1H8M5, Canada. mkaern@uottawa.ca
Nature Reviews. Genetics
|May 11, 2005
Summary
Cellular variability arises from gene expression noise. While often detrimental, this stochasticity can be advantageous, enabling adaptation and population heterogeneity during development.
Area of Science:
- Cellular and Molecular Biology
- Genetics
- Developmental Biology
Background:
- Genetically identical cells exhibit molecular and phenotypic variability.
- This variability is attributed to stochasticity in gene expression.
- Gene expression noise is typically associated with negative cellular consequences and disease.
Purpose of the Study:
- To explore the dual role of gene expression stochasticity in cellular function.
- To investigate the potential benefits of gene expression noise.
- To understand how stochasticity contributes to cellular adaptation and development.
Main Methods:
- Analysis of molecular content variation in identical cells.
- Observation of phenotypic differences under consistent environmental conditions.
- Literature review on the implications of gene expression stochasticity.
Main Results:
- Stochasticity in gene expression leads to significant cell-to-cell variation.
- Gene expression noise can be detrimental to cellular function.
- Gene expression noise offers adaptive advantages for cells facing environmental changes.
- Stochasticity facilitates population heterogeneity during differentiation.
Conclusions:
- Gene expression stochasticity presents a double-edged sword for cellular systems.
- While linked to disease, noise is crucial for cellular adaptability and development.
- Understanding stochasticity is key to comprehending cell behavior and evolution.
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