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Updated: Jun 5, 2026
07:44
Measuring Microbial Mutation Rates with the Fluctuation Assay
Published on: November 28, 2019
Evolution of molecular error rates and the consequences for evolvability
1Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA. rajon@email.arizona.edu
Summary
Gene expression errors can be avoided globally or locally. Intermediate population sizes allow for bistable evolutionary dynamics, potentially increasing evolvability by assimilating cryptic genetic variation.
Area of Science:
- Evolutionary biology
- Molecular genetics
Background:
- Gene expression involves predictable errors.
- Cryptic genetic sequences can have deleterious effects, such as protein misfolding.
- Organisms can avoid deleterious effects via global error avoidance or local error mitigation.
Purpose of the Study:
- To investigate the evolutionary dynamics of error avoidance strategies across different population sizes.
- To determine the conditions under which global or local solutions evolve.
- To assess the impact of these strategies on evolvability.
Main Methods:
- Theoretical modeling of evolutionary dynamics.
- Analysis of selection pressures in varying population sizes.
- Simulation of genetic assimilation processes.
Main Results:
- Global solutions (e.g., proofreading) evolve in small populations.
- Local solutions evolve in large populations, requiring strong selection on cryptic sites.
- Intermediate population sizes exhibit bistable dynamics, allowing either solution to emerge.
- The local solution promotes genetic assimilation of cryptic variation, enhancing evolvability.
Conclusions:
- Population size is a critical factor shaping the evolution of gene expression error management.
- Bistable evolutionary dynamics in intermediate populations can lead to increased evolvability.
- Understanding these mechanisms is key to comprehending genetic variation and adaptation.
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