Requirement for chloride channel function during the hepatitis C virus life cycle.
Bottom Line: Here, we show that HCV increases intracellular hepatic chloride (Cl(-)) influx that can be inhibited by selective Cl(-) channel blockers.Through pharmacological and small interfering RNA (siRNA)-mediated silencing, we demonstrate that Cl(-) channel inhibition is detrimental to HCV replication.This represents the first observation of the involvement of Cl(-) channels during the HCV life cycle.
Affiliation: School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom.Show MeSH
Related in: MedlinePlus
Mentions: Given these data, we investigated the molecular identity of the Cl− channel(s) required during the HCV life cycle. To date, nearly 40 different genes that, when expressed, increase Cl− conductance have been cloned. These include the Cl− intracellular-channel (CLIC) proteins cyclic AMP (cAMP) (CFTR)-, calcium (CaCC)-, voltage-activated Cl− channels and Cl−/H+ exchangers (CLCs) as well as ligand-gated Cl− channels [GABA(A), GABA(C), and glycine]. In hepatocytes, CLIC-1, ClC-2, ClC-3, ClC-5, and ClC-7 are expressed (9). We confirmed this by reverse transcription-PCR (RT-PCR) analysis (primer sequences are available upon request) and silenced this expression through small interfering RNA (siRNA) transfection (Fig. 4A). Figure 4B shows that ClC-2, ClC-3, ClC-5, and ClC-7 silencing significantly suppressed SGR–Feo–JFH-1 replication (52% ± 6%, 31% ± 16%, 48% ± 2%, and 50% ± 10% inhibition of luciferase activity, respectively). CLIC-1 knockdown displayed no discernible effects. Since some of these CLC channels and transporters are sensitive to NPPB and IAA-94; this confirmed the importance of Cl− influx during HCV replication.
Affiliation: School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom.