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Origin, Evolution, and Loss of Bacterial Small RNAs
H Auguste Dutcher1, Rahul Raghavan1
1Department of Biology and Center for Life in Extreme Environments, Portland State University, Portland, OR 97201.
Microbiology Spectrum
|April 7, 2018
Summary
Bacterial small RNAs (sRNAs) evolve through emergence, change, and loss. Their origins are diverse, and rapid evolution aids regulatory network understanding.
Area of Science:
- Microbiology
- Evolutionary Biology
- Genetics
Background:
- Bacterial noncoding small RNAs (sRNAs) are crucial for posttranscriptional gene regulation.
- The evolutionary trajectories and life cycles of bacterial sRNAs remain largely unexplored.
Purpose of the Study:
- To review and synthesize current knowledge on bacterial sRNA evolution.
- To elucidate the mechanisms of sRNA emergence, diversification, and loss in bacteria.
Main Methods:
- Compilation and analysis of existing studies on bacterial sRNA evolution.
- Comparative analysis of sRNA evolutionary dynamics with eukaryotic microRNAs.
Main Results:
- sRNAs originate through de novo emergence, duplication, or horizontal gene transfer.
- Rapid evolution and neofunctionalization are common, facilitated by partial target complementarity.
- sRNA loss can occur through adaptive or neutral evolutionary processes.
Conclusions:
- Understanding sRNA evolution is key to improving sRNA detection and genome annotation.
- Further evolutionary analyses will deepen insights into bacterial regulatory networks.
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