| Autor: |
Daino GL; Department of Life and Environmental Sciences , University of Cagliari , Cagliari 09042 , Italy., Frau A; Department of Life and Environmental Sciences , University of Cagliari , Cagliari 09042 , Italy., Sanna C; Department of Life and Environmental Sciences , University of Cagliari , Cagliari 09042 , Italy., Rigano D; Department of Pharmacy, School of Medicine and Surgery , University of Naples Federico II , Naples 80131 , Italy., Distinto S; Department of Life and Environmental Sciences , University of Cagliari , Cagliari 09042 , Italy., Madau V; Department of Life and Environmental Sciences , University of Cagliari , Cagliari 09042 , Italy., Esposito F; Department of Life and Environmental Sciences , University of Cagliari , Cagliari 09042 , Italy., Fanunza E; Department of Life and Environmental Sciences , University of Cagliari , Cagliari 09042 , Italy., Bianco G; Department of Life and Environmental Sciences , University of Cagliari , Cagliari 09042 , Italy., Taglialatela-Scafati O; Department of Pharmacy, School of Medicine and Surgery , University of Naples Federico II , Naples 80131 , Italy., Zinzula L; The Max-Planck Institute of Biochemistry , Department of Molecular Structural Biology , Martinsried 82152 , Germany., Maccioni E; Department of Life and Environmental Sciences , University of Cagliari , Cagliari 09042 , Italy., Corona A; Department of Life and Environmental Sciences , University of Cagliari , Cagliari 09042 , Italy., Tramontano E; Department of Life and Environmental Sciences , University of Cagliari , Cagliari 09042 , Italy.; Istituto di Ricerca Genetica e Biomedica , Consiglio Nazionale delle Ricerche (CNR) , Monserrato 09042 , Italy. |
| Abstrakt: |
Ebola virus (EBOV) is a filovirus that causes a severe and rapidly progressing hemorrhagic syndrome; a recent epidemic illustrated the urgent need for novel therapeutic agents because no drugs have been approved for treatment of Ebola virus. A key contribution to the high lethality observed during EBOV outbreaks comes from viral evasion of the host antiviral innate immune response in which viral protein VP35 plays a crucial role, blocking interferon type I production, first by masking the viral double-stranded RNA (dsRNA) and preventing its detection by the pattern recognition receptor RIG-I. Aiming to identify inhibitors of the interaction of VP35 with the viral dsRNA, counteracting the VP35 viral innate immune evasion, we established a new methodology for high-yield recombinant VP35 (rVP35) expression and purification and a novel and robust fluorescence-based rVP35-RNA interaction assay ( Z' factor of 0.69). Taking advantage of such newly established methods, we screened a small library of Sardinian natural extracts, identifying Limonium morisianum as the most potent inhibitor extract. A bioguided fractionation led to the identification of myricetin as the component that can inhibit rVP35-dsRNA interaction with an IC 50 value of 2.7 μM. Molecular docking studies showed that myricetin interacts with the highly conserved region of the VP35 RNA binding domain, laying the basis for further structural optimization of potent inhibitors of VP35-dsRNA interaction. |
