Host proteins associated with Hepatitis C virus encoded NS4A

Virus-associated cancers account for more than 12 % of all the cancers. Hepatitis C virus (HCV) infects nearly 3 % of the population worldwide and has emerged as a major causative agent of liver disease with a big impact on public health. The HCV non-structural protein NS4A is a 54-amino-acid polypeptide that serves as an essential co-factor for the NS3 serine protease. We report here on a proteomic study to identify cellular proteins associated with NS4A. The results of this study show an association of three host cellular proteins with NS4A including two novel NS4A interacting partners. Our data provide evidence for complex involving NS4A with previously unreported cellular proteins including housekeeping protein GAPDH, and PI3P-5 K which is involved in cellular protein trafficking to nucleus. These novel associations add to the diversity of NS4A functions in relation to the virus infection and subsequent pathogenesis.