Borna disease virus nucleoprotein inhibits type I interferon induction through the interferon regulatory factor 7 pathway.
The expression of type I interferon (IFN) is one of the most potent innate defences against viral infection in higher vertebrates. Borna disease virus (BDV) establishes persistent, noncytolytic infections in animals and in cultured cells. Early studies have shown that the BDV phosphoprotein can inhibit the activation of type I IFN through the TBK1-IRF3 pathway. The function of the BDV nucleoprotein in the inhibition of IFN activity is not yet clear. In this study, we demonstrated IRF7 activation and increased IFN-α/β expression in a BDV-persistently infected human oligodendroglia cell line following RNA interference-mediated BDV nucleoprotein silencing. Furthermore, we showed that BDV nucleoprotein prevented the nuclear localisation of IRF7 and inhibited endogenous IFN induction by poly(I:C), coxsackie virus B3 and IFN-β. Our findings provide evidence for a previously undescribed mechanism by which the BDV nucleoprotein inhibits type I IFN expression by interfering with the IRF7 pathway.
The Heilongjiang Key Laboratory of Immunity and Infection, Heilongjiang, China.
Wuqi
W
Song
Wenping
W
Kao
Aixia
A
Zhai
Jun
J
Qian
Yujun
Y
Li
Qingmeng
Q
Zhang
Hong
H
Zhao
Yunlong
Y
Hu
Hui
H
Li
Fengmin
F
Zhang
D001890:Borna Disease / Q000235:genetics* / Q000378:metabolism / Q000821:virology; D001891:Borna disease virus / Q000502:physiology*; D002460:Cell Line; D015536:Down-Regulation; D054884:Host-Pathogen Interactions; D006801:Humans; D050839:Interferon Regulatory Factor-7 / Q000032:analysis / Q000378:metabolism*; D007370:Interferon Type I / Q000235:genetics*; D009698:Nucleoproteins / Q000378:metabolism*; D015398:Signal Transduction; D014764:Viral Proteins / Q000378:metabolism*
D050839:Interferon Regulatory Factor-7; D007370:Interferon Type I; D009698:Nucleoproteins; D014764:Viral Proteins
IRF7; Nucleoprotein of BDV; Type I IFN