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Pseudouridine Modifications in Transfer RNA and tRNA Pseudouridine Synthases
1Department of Materials Science and Biotechnology, Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan.
Journal of Molecular Biology
|May 17, 2025
Summary
Pseudouridine is a common RNA modification crucial for protein synthesis accuracy and RNA structure. This review details pseudouridine synthases, their mechanisms, functions, and links to diseases.
Area of Science:
- Biochemistry
- Molecular Biology
- Genetics
Background:
- Pseudouridine is the most frequent modification in transfer RNA (tRNA) across all organisms.
- It is also found in other RNA types, including ribosomal, messenger, and nuclear RNAs.
- Pseudouridine synthases (PUS) enzymes catalyze this modification, with diverse specificities and functions.
Purpose of the Study:
- To review the reaction mechanisms and functions of pseudouridine synthases.
- To examine the six known families of pseudouridine synthases, detailing their structural similarities and variations.
- To highlight the emerging roles of pseudouridine and its modifying enzymes in viral infections and human diseases.
Main Methods:
- Literature review of pseudouridine synthases.
- Analysis of domain structures, motifs, and target uracil bases across different PUS families.
- Characterization of individual enzymes and their recently identified roles.
Main Results:
- Pseudouridine synthases exhibit varied substrate specificities, modifying tRNA, rRNA, snRNA, and mRNA.
- Functions of pseudouridine include tRNA structure stabilization and ensuring accurate protein synthesis, preventing frameshifts.
- Some PUS enzymes also act as RNA chaperones, aiding in RNA folding and stability.
Conclusions:
- Pseudouridine synthases are a diverse group of enzymes with critical roles in RNA metabolism and function.
- Understanding PUS mechanisms and functions provides insights into fundamental biological processes.
- Emerging evidence links pseudouridine and PUS to human health, including viral pathogenesis and disease development.
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