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Generation and Assembly of Virus-Specific Nucleocapsids of the Respiratory Syncytial Virus
Published on: July 27, 2021
Characterization of an extremely basic protein derived from granulosis virus nucleocapsids
K A Tweeten1, L A Bulla, R A Consigli
1Division of Biology, Section of Virology and Oncology, Kansas State University, Manhattan, Kansas 66506.
Journal of Virology
|February 1, 1980
Summary
Researchers identified a basic protein (VP12) within Plodia interpunctella granulosis virus nucleocapsids. This virus-specific protein, rich in arginine and histidine, is associated with viral DNA, suggesting a role in DNA packaging.
Area of Science:
- Virology
- Molecular Biology
- Insect Pathology
Background:
- Granulosis viruses are insect pathogens with complex nucleocapsid structures.
- Understanding viral protein composition is crucial for elucidating infection mechanisms.
Purpose of the Study:
- To characterize the protein components of Plodia interpunctella granulosis virus nucleocapsids.
- To identify and analyze a specific basic protein within the nucleocapsid structure.
Main Methods:
- Nucleocapsid isolation using Nonidet P-40 treatment.
- Polypeptide analysis via SDS-PAGE and acetic acid-urea gel electrophoresis.
- Amino acid composition analysis.
- Electron microscopy for DNA-protein complex visualization.
Main Results:
- Nucleocapsids comprised eight polypeptides, including a major 12,500 MW protein (VP12).
- VP12 was selectively extracted with sulfuric acid and showed high basic amino acid content (39% arginine and histidine).
- Similar basic proteins were found in other baculoviruses; VP12 was virus-specific and located in the nucleocapsid core, associated with viral DNA.
Conclusions:
- VP12 is a virus-specific, basic DNA-binding protein in P. interpunctella granulosis virus.
- This protein likely functions in viral DNA condensation and packaging within the nucleocapsid.
- The findings contribute to understanding baculovirus structural proteins and their roles.
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