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Updated: Aug 23, 2025

Generation and Assembly of Virus-Specific Nucleocapsids of the Respiratory Syncytial Virus
Published on: July 27, 2021
The Tobacco Mosaic Virus Origin of Assembly Sequence is Dispensable for Specific Viral RNA Encapsidation but
Keith Saunders1, Eva C Thuenemann1, Hadrien Peyret1
1Biochemistry and Metabolism, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK.
Abstract:
We have investigated whether the presence of the origin of assembly sequence (OAS) of tobacco mosaic virus (TMV) is necessary for the specific encapsidation of replicating viral RNA. To this end TMV coat protein was expressed from replicating RNA constructs with or without the OAS in planta. In both cases the replicating RNA was specifically encapsidated to give nucleoprotein nanorods, though the yield in the absence of the OAS was reduced to about 60% of that in its presence. Moreover, the nanorods generated in the absence of the OAS were more heterogeneous in length and contained frequent structural discontinuities. These results strongly suggest that the function of the OAS is to provide a unique site for the initiation of viral assembly, leading to a one-start helix, rather than the selection of virus RNA for packaging.
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