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Measuring shifts in function and evolutionary opportunity using variability profiles: a case study of the globins
1Department of Zoology and Genetics, Iowa State University, Ames, IA 50011, USA.
Journal of Molecular Evolution
|October 12, 2000
Summary
Evolutionary freedom to vary can be measured using sequence variability profiles. These profiles reveal molecular function shifts, as seen in hemoglobin and myoglobin evolution between species.
Area of Science:
- Evolutionary biology
- Molecular evolution
- Bioinformatics
Background:
- Sequence variability profiles offer insights into evolutionary potential.
- Comparative analysis of these profiles can identify molecular functional shifts.
- Hemoglobin and myoglobin serve as model systems for studying protein evolution.
Purpose of the Study:
- To demonstrate shifts in molecular function using sequence variability profiles.
- To compare evolutionary divergence in hemoglobin and myoglobin across different clades.
- To explore the concept of evolutionary opportunity and its relationship to protein function.
Main Methods:
- Measurement and comparison of sequence variability profiles across aligned protein sequences.
- Analysis of variability differences between alpha and beta hemoglobin subunits.
- Comparative analysis of myoglobin variability profiles in whales and primates.
Main Results:
- A functional shift was identified between the alpha and beta subunits of hemoglobin.
- Myoglobin variability profiles differ significantly between whales and primates.
- These differences suggest adaptive shifts related to oxygen storage in whales.
Conclusions:
- Sequence variability analysis is a powerful tool for detecting molecular functional changes.
- Evolutionary opportunity and functional constraints can be quantitatively assessed.
- Understanding protein function requires considering evolutionary context and genotype-phenotype mapping.
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