Self-capping of nucleoprotein filaments protects Newcastle Disease Virus genome
- Kunming Medical University, China
- ShanghaiTech University, China
- Chinese Academy of Sciences, China
- Yangzhou University, China
- Fujian Normal University, China
Abstract
Non-segmented negative-strand RNA viruses, such as Measles, Ebola and Newcastle disease viruses (NDV), encapsidate viral genomic RNAs into helical nucleocapsids which serve as the template for viral replication and transcription. Here, the clam-shaped nucleocapsid structure, where the NDV viral genome is sequestered, was determined at 4.8 Å resolution by cryo-electron microscopy. The clam-shaped structure is composed of two single-turn spirals packed in a back-to-back mode, and the tightly packed structure functions as a seed for nucleocapsid to assemble from both directions and grows into double-headed filaments with two separate RNA strings inside. Disruption of this structure by mutations on its loop interface yielded a single-headed unfunctional filament.
Data availability
The cryo-EM density map has been deposited in EMDB with the accession number EMD-9793. The atom coordinates of the structure have been deposited in PDB with the PDB ID 6JC3.
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The Cryo-EM structure of nucleoprotein-RNA complex of Newcastle disease virusRCSB Protein Data Bank, 6JC3.
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The Cryo-EM structure of nucleoprotein-RNA complex of Newcastle disease virusElectron Microscopy Data Bank, EMD-9793.
Article and author information
Author details
Funding
National Nature Science Foundation of China grant (31330019)
- Zhi-Jie Liu
National Nature Science Foundation of China grant (31770948)
- Songying Ouyang
National Nature Science Foundation of China grant (31570875)
- Songying Ouyang
National Natural Science Foundation of China grant (81590761)
- Songying Ouyang
the National Key R&D program of China (2017YFA0504800)
- Qing-Tao Shen
Yunnan Provincial Science and Technology Department Project (2016FC007)
- Zhi-Jie Liu
The Pujiang Talent program (17PJ1406700)
- Qing-Tao Shen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Song et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Self-capping of nucleoprotein filaments protects Newcastle Disease Virus genome
eLife 8:e45057.
https://doi.org/10.7554/eLife.45057
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