A conserved basic loop in hepatitis C virus p7 protein is required for amantadine-sensitive ion channel activity in mammalian cells but is dispensable for localization to mitochondria

• Published in: Journal of general virology 2004-02, Vol.85 (2), p.451-461
• Main Authors: Griffin, Stephen D. C, Harvey, Ruth, Clarke, Dean S, Barclay, Wendy S, Harris, Mark, Rowlands, David J
• Format: Article
• Language: English
• Subjects: Amantadine - pharmacology; Amino Acid Sequence; Animals; Antiviral Agents - pharmacology; Biological and medical sciences; Cell Line; Fundamental and applied biological sciences. Psychology; Hepacivirus - drug effects; Hepacivirus - genetics; Hepacivirus - metabolism; Human viral diseases; Humans; Infectious diseases; Ion Channels - antagonists & inhibitors; Ion Channels - metabolism; Mammals; Medical sciences; Microbiology; Miscellaneous; Mitochondria - metabolism; Molecular Sequence Data; Mutation; Protein Structure, Secondary; Sequence Alignment; Viral diseases; Viral hepatitis; Viral Matrix Proteins - metabolism; Viral Proteins - antagonists & inhibitors; Viral Proteins - genetics; Viral Proteins - metabolism; Virology
• ISSN: 0022-1317; 1465-2099
• DOI: 10.1099/vir.0.19634-0

1 Astbury Centre of Molecular Biology, School of Biochemistry and Microbiology, University of Leeds, Leeds LS2 9JT, UK 2 School of Animal and Microbial Sciences, University of Reading, Whiteknights, PO Box 228, Reading, Berkshire RG6 6AJ, UK 3 Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK Correspondence David J. Rowlands D.J.Rowlands{at}bmb.leeds.ac.uk We previously identified the function of the hepatitis C virus (HCV) p7 protein as an ion channel in artificial lipid bilayers and demonstrated that this in vitro activity is inhibited by amantadine. Here we show that the ion channel activity of HCV p7 expressed in mammalian cells can substitute for that of influenza virus M2 in a cell-based assay. This was also the case for the p7 from the related virus, bovine viral diarrhoea virus (BVDV). Moreover, amantadine was shown to abrogate HCV p7 function in this assay at a concentration that specifically inhibits M2. Mutation of a conserved basic loop located between the two predicted trans -membrane alpha helices rendered HCV p7 non-functional as an ion channel. The intracellular localization of p7 was unaffected by this mutation and was found to overlap significantly with membranes associated with mitochondria. Demonstration of p7 ion channel activity in cellular membranes and its inhibition by amantadine affirm the protein as a target for future anti-viral chemotherapy. Published ahead of print on 14 November 2003 as DOI 10.1099/vir.0.19634-0. Present address: PHLS Central Public Health Laboratory, Colindale, London NW9 5HT, UK.