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Diversity-Generating Retroelements in Prokaryotic Immunity.
Ilya S Belalov1, Arseniy A Sokolov1,2, Andrey V Letarov1
1Laboratory of Microbial Viruses, Winogradsky Institute of Microbiology RC Biotechnology RAS, 117312 Moscow, Russia.
International Journal of Molecular Sciences
|March 29, 2023
Summary
Prokaryotes may use diversity-generating retroelements to preemptively create defense proteins against unknown invaders, similar to how mammals generate immune defenses. This study identifies potential prokaryotic defense systems based on this principle.
Area of Science:
- Microbiology
- Immunology
- Bioinformatics
Background:
- Adaptive immunity varies between prokaryotes (e.g., CRISPR-Cas) and mammals (antibodies, T-cell receptors).
- Mammalian adaptive immunity relies on pre-generated diverse immune receptors for pathogen recognition.
Purpose of the Study:
- To test the hypothesis that prokaryotes utilize diversity-generating retroelements for preemptive defense protein production.
- To identify novel prokaryotic defense systems analogous to mammalian adaptive immunity.
Main Methods:
- Bioinformatic analysis of prokaryotic genomes and genetic elements.
- Identification and characterization of diversity-generating retroelement-associated systems.
Main Results:
- Several candidate prokaryotic defense systems potentially utilizing diversity-generating retroelements were identified.
- Evidence suggests a mechanism for generating diverse defense proteins in prokaryotes prior to encountering specific threats.
Conclusions:
- Prokaryotes may employ diversity-generating retroelements as a strategy for adaptive immunity.
- This finding expands our understanding of microbial defense mechanisms and evolutionary strategies.
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