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The hepatitis C virus RNA-dependent RNA polymerase membrane insertion sequence is a transmembrane segment.

ABSTRACT: The hepatitis C virus (HCV) RNA-dependent RNA polymerase (RdRp) belongs to a class of membrane proteins termed tail-anchored proteins. Here, we show that the HCV RdRp C-terminal membrane insertion sequence traverses the phospholipid bilayer as a transmembrane segment. Moreover, the HCV RdRp was found to be retained in the endoplasmic reticulum (ER) or an ER-derived modified compartment both following transient transfection and in the context of a subgenomic replicon. An absolutely conserved GVG motif was not essential for membrane insertion but possibly provides a docking site for transmembrane protein-protein interactions. These findings have important implications for the functional architecture of the HCV replication complex.

SUBMITTER: Ivashkina N

PROVIDER: S-EPMC136709 | biostudies-literature | 2002 Dec

REPOSITORIES: biostudies-literature

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The hepatitis C virus RNA-dependent RNA polymerase membrane insertion sequence is a transmembrane segment.

Ivashkina Natalia N Wölk Benno B Lohmann Volker V Bartenschlager Ralf R Blum Hubert E HE Penin François F Moradpour Darius D

Journal of virology 20021201 24

The hepatitis C virus (HCV) RNA-dependent RNA polymerase (RdRp) belongs to a class of membrane proteins termed tail-anchored proteins. Here, we show that the HCV RdRp C-terminal membrane insertion sequence traverses the phospholipid bilayer as a transmembrane segment. Moreover, the HCV RdRp was found to be retained in the endoplasmic reticulum (ER) or an ER-derived modified compartment both following transient transfection and in the context of a subgenomic replicon. An absolutely conserved GVG ...[more]

PMID: 12438637

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