Structural highlights
Function
[VP35_EBORR] Acts as a polymerase cofactor in the RNA polymerase transcription and replication complex. Prevents establishment of cellular antiviral state by blocking virus-induced phosphorylation and activation of interferon regulatory factor 3 (IRF3), a transcription factor critical for the induction of interferons alpha and beta. The mechanism by which this blockage occurs remains incompletely defined, a hypothesis suggests that VP35 dsRNA-binding activity prevents activation of IRF3 by sequestering dsRNA. Also inhibits the antiviral effect mediated by the interferon-induced, double-stranded RNA-activated protein kinase EIF2AK2/PKR (By similarity).
Publication Abstract from PubMed
The multifunctional virion protein 35 (VP35) of ebolaviruses is a critical determinant of virulence and pathogenesis indispensable for viral replication and host innate immune evasion. Essential for VP35 function is homo-oligomerization via a coiled-coil motif. Here we report crystal structures of VP35 oligomerization domains from the prototypic Ebola virus (EBOV) and the non-pathogenic Reston virus (RESTV), together with a comparative biophysical characterization of the domains from all known species of the Ebolavirus genus. EBOV and RESTV VP35 oligomerization domains form bipartite parallel helix bundles with a canonical coiled coil in the N-terminal half and increased plasticity in the highly conserved C-terminal half. The domain assembles into trimers and tetramers in EBOV, whereas it exclusively forms tetramers in all other ebolavirus species. Substitution of coiled-coil leucine residues critical for immune antagonism leads to aberrant oligomerization. A conserved arginine involved in inter-chain salt bridges stabilizes the VP35 oligomerization domain and modulates between coiled-coil oligomeric states.
Structures of Ebola and Reston Virus VP35 Oligomerization Domains and Comparative Biophysical Characterization in All Ebolavirus Species.,Zinzula L, Nagy I, Orsini M, Weyher-Stingl E, Bracher A, Baumeister W Structure. 2018 Oct 5. pii: S0969-2126(18)30335-6. doi:, 10.1016/j.str.2018.09.009. PMID:30482729[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Zinzula L, Nagy I, Orsini M, Weyher-Stingl E, Bracher A, Baumeister W. Structures of Ebola and Reston Virus VP35 Oligomerization Domains and Comparative Biophysical Characterization in All Ebolavirus Species. Structure. 2018 Oct 5. pii: S0969-2126(18)30335-6. doi:, 10.1016/j.str.2018.09.009. PMID:30482729 doi:http://dx.doi.org/10.1016/j.str.2018.09.009
