Emerging data indicated that HCV subverts the antiviral activity of interferon(IFN);however,whether HCV core protein contributes to the process remains controversial.In the present study,we examined the effect of HCV ...Emerging data indicated that HCV subverts the antiviral activity of interferon(IFN);however,whether HCV core protein contributes to the process remains controversial.In the present study,we examined the effect of HCV core protein on interferon-induced antiviral gene expression and whether the effect is involved in the activation and negative regulation of the Jak/STAT signaling pathway.Our results showed that,following treatment with IFN-α,the transcription of PKR,MxA and 2'-5'OAS were down-regulated in HepG2 cells expressing the core protein.In the presence of HCV core protein,ISRE-dependent luciferase activity also decreased.Further study indicated that the core protein could inhibit the tyrosine phosphorylation of STAT1,whereas the level of STAT1 expression was unchanged.Accordingly,SOCS3,the negative regulator of the Jak/STAT pathway,was induced by HCV core protein.These results suggests that HCV core protein may interfere with the expression of some interferon-induced antiviral genes by inhibiting STAT1 phosphorylation and induction of SOCS3.展开更多
文摘Emerging data indicated that HCV subverts the antiviral activity of interferon(IFN);however,whether HCV core protein contributes to the process remains controversial.In the present study,we examined the effect of HCV core protein on interferon-induced antiviral gene expression and whether the effect is involved in the activation and negative regulation of the Jak/STAT signaling pathway.Our results showed that,following treatment with IFN-α,the transcription of PKR,MxA and 2'-5'OAS were down-regulated in HepG2 cells expressing the core protein.In the presence of HCV core protein,ISRE-dependent luciferase activity also decreased.Further study indicated that the core protein could inhibit the tyrosine phosphorylation of STAT1,whereas the level of STAT1 expression was unchanged.Accordingly,SOCS3,the negative regulator of the Jak/STAT pathway,was induced by HCV core protein.These results suggests that HCV core protein may interfere with the expression of some interferon-induced antiviral genes by inhibiting STAT1 phosphorylation and induction of SOCS3.
