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Published on: September 20, 2011
Evolution of two-component signal transduction
K K Koretke1, A N Lupas, P V Warren
1SmithKline Beecham Pharmaceuticals, Collegeville, Pennsylvania 19426-0989, USA.
Molecular Biology and Evolution
|December 9, 2000
Summary
Two-component signal transduction (TCST) systems, crucial for bacterial environmental responses, originated in bacteria and spread via gene transfer. Their components coevolved, with serine kinases evolving independently multiple times.
Area of Science:
- Microbiology
- Evolutionary Biology
- Biochemistry
Background:
- Two-component signal transduction (TCST) systems regulate cellular responses to environmental stimuli in bacteria, archaea, and eukaryotes.
- These systems, comprising histidine kinases and response regulators, are vital for microbial adaptation.
- The evolutionary history and interrelationships of TCST components remain largely uncharacterized.
Purpose of the Study:
- To elucidate the evolutionary relationships and ancestry of two-component signal transduction system components.
- To investigate the origins and diversification of histidine kinases and response regulators across different domains of life.
- To explore the evolution of kinase activity within the TCST superfamily.
Main Methods:
- Phylogenetic analysis of histidine kinases and response regulators from 20 genomes using distance methods.
- Comparative structural analysis of TCST kinase domains with other protein kinases.
- Examination of domain variability and sequence congruence across phylogenetic clusters.
Main Results:
- Phylogenetic trees revealed 11 distinct clusters with extensive congruence, indicating conserved evolutionary trajectories.
- Eukaryotic and archaeal TCST sequences clustered separately, with eukaryotes showing high domain variability.
- Kinases were monophyletic within their superfamily, and structural similarity to eukaryotic protein kinases was observed.
Conclusions:
- TCST systems are of bacterial origin, disseminated to archaea and eukaryotes through lateral gene transfer.
- Coevolution of TCST components is evident, with limited evidence for recombination driving diversification.
- Independent evolution of serine kinases occurred multiple times, often with loss of cognate response regulators.
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