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Stuck in the middle: structural insights into the role of the gH/gL heterodimer in herpesvirus entry.

ABSTRACT: Enveloped viruses enter cells by fusing the viral and cellular membranes, and most use a single viral envelope protein that combines receptor-binding and fusogenic functions. In herpesviruses, these functions are distributed among multiple proteins: the conserved fusion protein gB, various non-conserved receptor-binding proteins, and the conserved gH/gL heterodimer that curiously lacks an apparent counterpart in other enveloped viruses. Recent structural studies of gH/gL from HSV-2 and EBV revealed a unique complex with no structural or functional similarity to other viral proteins. Here we analyzed gH/gL structures and highlighted important functional regions. We propose that gH/gL functions as an adaptor that transmits the triggering signals from various non-conserved inputs to the highly conserved fusion protein gB.

SUBMITTER: Stampfer SD

PROVIDER: S-EPMC3562363 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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Stuck in the middle: structural insights into the role of the gH/gL heterodimer in herpesvirus entry.

Stampfer Samuel D SD Heldwein Ekaterina E EE

Current opinion in virology 20121026 1

Enveloped viruses enter cells by fusing the viral and cellular membranes, and most use a single viral envelope protein that combines receptor-binding and fusogenic functions. In herpesviruses, these functions are distributed among multiple proteins: the conserved fusion protein gB, various non-conserved receptor-binding proteins, and the conserved gH/gL heterodimer that curiously lacks an apparent counterpart in other enveloped viruses. Recent structural studies of gH/gL from HSV-2 and EBV revea ...[more]

PMID: 23107819

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