Structural and Functional Analysis of the HCV p7 Protein
The p7 membrane polypeptide from HCV is essential for virus infection. It exhibits ion-channel activity reported to be specifically blocked by various compounds. These properties make p7 an attractive candidate target for antiviral intervention to combat viral hepatitis C infection. In this context, in vitro functional analyses of isolated p7 coupled to structural characterization are critical for further understanding of the molecular mechanisms of p7 ion-channel activity and for the development of new antiviral drugs. We present here in vitro assays designed to purify synthetic p7 by RP-HPLC, to investigate its ion-channel properties by means of planar lipid-bilayer assays and patch-clamp recordings after reconstitution into liposomes, and to analyze its structural features by circular dichroism (CD), nuclear magnetic resonance (NMR), and molecular dynamics (MD).
Key WordsIons-channel activity viroporin RP-HPLC circular dichroism (CD) nuclear magnetic resonance (NMR) molecular dynamics (MD)
This work was supported by the French Centre National de la Recherche Scientifique (CNRS) and Universitéde Lyon, by grants QLK2-CT1999-00356 and QLK2-CT2002-01329 from the European Commission, and by the French National Agency for Research on AIDS and Viral Hepatitis (ANRS). CD experiments were performed on the platform “Production et Analyse de Protéines” from the IFR 128 BioSciences Gerland Lyon-Sud.
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