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Structure of hepatitis E virion-sized particle reveals an RNA-dependent viral assembly pathway.

ABSTRACT: Hepatitis E virus (HEV) induces acute hepatitis in humans with a high fatality rate in pregnant women. There is a need for anti-HEV research to understand the assembly process of HEV native capsid. Here, we produced a large virion-sized and a small T=1 capsid by expressing the HEV capsid protein in insect cells with and without the N-terminal 111 residues, respectively, for comparative structural analysis. The virion-sized capsid demonstrates a T=3 icosahedral lattice and contains RNA fragment in contrast to the RNA-free T=1 capsid. However, both capsids shared common decameric organization. The in vitro assembly further demonstrated that HEV capsid protein had the intrinsic ability to form decameric intermediate. Our data suggest that RNA binding is the extrinsic factor essential for the assembly of HEV native capsids.

SUBMITTER: Xing L

PROVIDER: S-EPMC2963395 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature

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Structure of hepatitis E virion-sized particle reveals an RNA-dependent viral assembly pathway.

Xing Li L Li Tian-Cheng TC Mayazaki Naoyuki N Simon Martha N MN Wall Joseph S JS Moore Mary M Wang Che-Yen CY Takeda Naokazu N Wakita Takaji T Miyamura Tatsuo T Cheng R Holland RH

The Journal of biological chemistry 20100818 43

Hepatitis E virus (HEV) induces acute hepatitis in humans with a high fatality rate in pregnant women. There is a need for anti-HEV research to understand the assembly process of HEV native capsid. Here, we produced a large virion-sized and a small T=1 capsid by expressing the HEV capsid protein in insect cells with and without the N-terminal 111 residues, respectively, for comparative structural analysis. The virion-sized capsid demonstrates a T=3 icosahedral lattice and contains RNA fragment i ...[more]

PMID: 20720013

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