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Updated: Nov 7, 2025

Generation and Assembly of Virus-Specific Nucleocapsids of the Respiratory Syncytial Virus
Published on: July 27, 2021
The structure of a virus-encoded nucleosome
Marco Igor Valencia-Sánchez1, Stephen Abini-Agbomson1, Miao Wang1
1Skirball Institute of Biomolecular Medicine, Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, USA.
Marseillevirus histones, Hβ-Hα and Hδ-Hγ, mimic eukaryotic histones H2B-H2A and H4-H3. These viral proteins form nucleosome-like structures, organizing viral DNA similarly to eukaryotic chromatin.
Area of Science:
- Virology
- Structural Biology
- Molecular Biology
Background:
- Large DNA viruses, such as Marseilleviridae, possess unique genetic elements.
- Eukaryotic histones package DNA into nucleosomes, forming chromatin.
Purpose of the Study:
- To investigate the structural and functional similarities between viral histones from Marseillevirus and eukaryotic histones.
- To determine if viral histones can form nucleosome-like structures.
Main Methods:
- Structural analysis of Marseillevirus histone pairs (Hβ-Hα and Hδ-Hγ).
- Comparative structural analysis with eukaryotic histone pairs (H2B-H2A and H4-H3).
- DNA binding assays to assess nucleosome formation.
Main Results:
- Marseillevirus histone pairs Hβ-Hα and Hδ-Hγ exhibit structural homology to eukaryotic H2B-H2A and H4-H3, respectively.
- These viral histones form stable heterodimers, termed 'forced' heterodimers.
- A heterotetramer assembled from these heterodimers successfully organized DNA into structures resembling canonical eukaryotic nucleosomes.
Conclusions:
- Marseillevirus employs histone proteins that are structurally analogous to eukaryotic histones.
- Viral histones can assemble DNA into nucleosome-like structures, suggesting a conserved mechanism for genome organization across viruses and eukaryotes.
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