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Viral Capsid and Polymerase in Reoviridae

Overview
Journal Subcell Biochem
Publisher Springer
Specialty Biochemistry
Date 2022 Sep 23
PMID 36151388
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Abstract

The members of the family Reoviridae (reoviruses) consist of 9-12 discrete double-stranded RNA (dsRNA) segments enclosed by single, double, or triple capsid layers. The outer capsid proteins of reoviruses exhibit the highest diversity in both sequence and structural organization. By contrast, the conserved RNA-dependent RNA polymerase (RdRp) structure in the conserved innermost shell in all reoviruses suggests that they share common transcriptional regulatory mechanisms. After reoviruses are delivered into the cytoplasm of a host cell, their inner capsid particles (ICPs) remain intact and serve as a stable nanoscale machine for RNA transcription and capping performed using enzymes in ICPs. Advances in cryo-electron microscopy have enabled the reconstruction at near-atomic resolution of not only the icosahedral capsid, including capping enzymes, but also the nonicosahedrally distributed complexes of RdRps within the capsid at different transcriptional stages. These near-atomic resolution structures allow us to visualize highly coordinated structural changes in the related enzymes, genomic RNA, and capsid protein during reovirus transcription. In addition, reoviruses encode their own enzymes for nascent RNA capping before RNA releasing from their ICPs.

References
1.
Appleby T, Perry J, Murakami E, Barauskas O, Feng J, Cho A . Viral replication. Structural basis for RNA replication by the hepatitis C virus polymerase. Science. 2015; 347(6223):771-5. DOI: 10.1126/science.1259210. View

2.
Auguste A, Kaelber J, Fokam E, Guzman H, Carrington C, Erasmus J . A newly isolated reovirus has the simplest genomic and structural organization of any reovirus. J Virol. 2014; 89(1):676-87. PMC: 4301156. DOI: 10.1128/JVI.02264-14. View

3.
Borodavka A, Dykeman E, Schrimpf W, Lamb D . Protein-mediated RNA folding governs sequence-specific interactions between rotavirus genome segments. Elife. 2017; 6. PMC: 5621836. DOI: 10.7554/eLife.27453. View

4.
Borsa J, GRAHAM A . Reovirus: RNA polymerase activity in purified virions. Biochem Biophys Res Commun. 1968; 33(6):895-901. DOI: 10.1016/0006-291x(68)90396-3. View

5.
Boyce M, Wehrfritz J, Noad R, Roy P . Purified recombinant bluetongue virus VP1 exhibits RNA replicase activity. J Virol. 2004; 78(8):3994-4002. PMC: 374272. DOI: 10.1128/jvi.78.8.3994-4002.2004. View