摘要
Dengue virus(DENV) and Zika virus(ZIKV) have spread throughout many countries in the developing world and infect millions of people every year, causing severe harm to human health and the economy. Unfortunately, there are few effective vaccines and therapies available against these viruses. Therefore, the discovery of new antiviral agents is critical.Herein, a scorpion venom peptide(Smp76) characterized from Scorpio maurus palmatus was successfully expressed and purified in Escherichia coli BL21(DE3). The recombinant Smp76(rSmp76) was found to effectively inhibit DENV and ZIKV infections in a dose-dependent manner in both cultured cell lines and primary mouse macrophages. Interestingly,rSmp76 did not inactivate the viral particles directly but suppressed the established viral infection, similar to the effect of interferon(IFN)-b. Mechanistically, rSmp76 was revealed to upregulate the expression of IFN-b by activating interferon regulatory transcription factor 3(IRF3) phosphorylation, enhancing the type-Ⅰ IFN response and inhibiting viral infection.This mechanism is significantly different from traditional virucidal antimicrobial peptides(AMPs). Overall, the scorpion venom peptide Smp76 is a potential new antiviral agent with a unique mechanism involving type-Ⅰ IFN responses,demonstrating that natural AMPs can enhance immunity by functioning as immunomodulators.
Dengue virus(DENV) and Zika virus(ZIKV) have spread throughout many countries in the developing world and infect millions of people every year, causing severe harm to human health and the economy. Unfortunately, there are few effective vaccines and therapies available against these viruses. Therefore, the discovery of new antiviral agents is critical.Herein, a scorpion venom peptide(Smp76) characterized from Scorpio maurus palmatus was successfully expressed and purified in Escherichia coli BL21(DE3). The recombinant Smp76(rSmp76) was found to effectively inhibit DENV and ZIKV infections in a dose-dependent manner in both cultured cell lines and primary mouse macrophages. Interestingly,rSmp76 did not inactivate the viral particles directly but suppressed the established viral infection, similar to the effect of interferon(IFN)-b. Mechanistically, rSmp76 was revealed to upregulate the expression of IFN-b by activating interferon regulatory transcription factor 3(IRF3) phosphorylation, enhancing the type-Ⅰ IFN response and inhibiting viral infection.This mechanism is significantly different from traditional virucidal antimicrobial peptides(AMPs). Overall, the scorpion venom peptide Smp76 is a potential new antiviral agent with a unique mechanism involving type-Ⅰ IFN responses,demonstrating that natural AMPs can enhance immunity by functioning as immunomodulators.
基金
supported by grants from National Science Fund of China (Nos. 31572289, 31872239 and 81630091)
International S&T Cooperation Program of China (No. S2016G3110)
Hubei Science Fund (Nos. 2015CFA042 and 2016CFA018)
China-Kazakhstan Cooperation Program (No. CK-07-09)
Fundamental Research Funds for the Central Universities in China (Nos. 2042017kf0242 and 2042017kf0199)
financial support from Higher Education Commission (HEC) of Pakistan
