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Updated: Sep 8, 2025
12:20
Bacterial Artificial Chromosomes: A Functional Genomics Tool for the Study of Positive-strand RNA Viruses
Published on: December 29, 2015
21.5K
Structural dynamics of dengue virus UTRs and their cyclization.
Zachary E Robinson1, Higor Sette Pereira1, Michael H D'Souza1
1Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, Lethbridge, Alberta, Canada.
Biophysical Journal
|September 7, 2025
Summary
Dengue virus (DENV) RNA structures were studied to understand replication. Researchers revealed flexible RNA conformations crucial for DENV cyclization, offering new drug targets.
Area of Science:
- Virology
- Structural Biology
- Molecular Biology
Background:
- Dengue virus (DENV) causes significant global health issues, with ~400 million infections annually.
- DENV replication relies on RNA-RNA interactions mediated by untranslated regions (UTRs).
- Understanding DENV UTR structure is key to inhibiting viral replication.
Purpose of the Study:
- To investigate the structural organization and binding properties of DENV 5' and 3' UTRs.
- To elucidate the conformational flexibility of DENV UTRs during replication.
- To provide insights for developing targeted antiviral therapies.
Main Methods:
- In vitro purification of DENV 5' and 3' UTRs.
- Biophysical techniques including small-angle X-ray scattering (SAXS).
- Computational methods for structural and binding analysis.
Main Results:
- DENV 5' and 3' UTRs bind with high affinity (40 nM) in a 1:1 stoichiometry.
- SAXS provided the first structural characterization of DENV UTRs, revealing multiple conformations.
- Key features of structural adaptability and dynamic folding were identified.
Conclusions:
- The study enhances understanding of DENV cyclization mechanisms.
- Flexible RNA conformations are critical for DENV replication.
- Findings pave the way for novel therapeutic strategies targeting viral RNA structures.
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