Maize Streak Virus: Single and Gemini Capsid Architecture.
Antonette Bennett1, Joshua A Hull1, Mario Mietzsch1
1Department of Biochemistry and Molecular Biology, College of Medicine Center for Structural Biology, McKnight Brain Institute, University of Florida, Gainesville, FL 32610-0245, USA.
Viruses
|January 8, 2025
Summary
Geminiviruses, important plant pathogens, have two capsid structures. This study reveals their high-resolution cryo-EM structures, detailing coat protein interactions and suggesting antiviral targets.
Area of Science:
- Structural virology
- Plant pathology
- Biophysics
Background:
- Geminiviruses are single-stranded DNA (ssDNA) plant viruses with significant agricultural and economic impact.
- Their capsids exhibit two distinct architectural forms: T = 1 icosahedral and twinned quasi-isometric.
Purpose of the Study:
- To determine the high-resolution structures of both capsid forms of the maize streak virus using cryo-electron microscopy (cryo-EM).
- To analyze coat protein (CP) and CP-genome interactions governing capsid assembly.
- To provide a structural atlas for Geminiviridae and identify potential antiviral targets.
Main Methods:
- Cryo-electron microscopy (cryo-EM) was employed to resolve the structures.
- Comparative structural and sequence analysis of Geminiviridae members.
Main Results:
- High-resolution structures of both T = 1 icosahedral and twinned quasi-isometric capsids of maize streak virus were obtained.
- Detailed insights into coat protein (CP) and CP-genome interactions were elucidated.
- Structural conservation across Geminiviridae members (60-95%) was observed, contrasting with lower sequence similarity (21-30%).
Conclusions:
- The study provides a comprehensive structural understanding of Geminivirus capsid assembly.
- Identified structural conservation suggests potential broad-spectrum antiviral strategies.
- The findings highlight targetable regions on Geminivirus capsids for antiviral development.
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