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Hepatitis A Virus Genome Organization and Replication Strategy.

ABSTRACT: Hepatitis A virus (HAV) is a positive-strand RNA virus classified in the genus Hepatovirus of the family Picornaviridae It is an ancient virus with a long evolutionary history and multiple features of its capsid structure, genome organization, and replication cycle that distinguish it from other mammalian picornaviruses. HAV proteins are produced by cap-independent translation of a single, long open reading frame under direction of an inefficient, upstream internal ribosome entry site (IRES). Genome replication occurs slowly and is noncytopathic, with transcription likely primed by a uridylated protein primer as in other picornaviruses. Newly produced quasi-enveloped virions (eHAV) are released from cells in a nonlytic fashion in a unique process mediated by interactions of capsid proteins with components of the host cell endosomal sorting complexes required for transport (ESCRT) system.

SUBMITTER: McKnight KL

PROVIDER: S-EPMC6280712 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Hepatitis A Virus Genome Organization and Replication Strategy.

McKnight Kevin L KL Lemon Stanley M SM

Cold Spring Harbor perspectives in medicine 20181203 12

Hepatitis A virus (HAV) is a positive-strand RNA virus classified in the genus <i>Hepatovirus</i> of the family <i>Picornaviridae</i> It is an ancient virus with a long evolutionary history and multiple features of its capsid structure, genome organization, and replication cycle that distinguish it from other mammalian picornaviruses. HAV proteins are produced by cap-independent translation of a single, long open reading frame under direction of an inefficient, upstream internal ribosome entry s ...[more]

PMID: 29610147

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