Characterization of the Crimean-Congo hemorrhagic fever virus nucleoprotein and RNA s-segment panhandle complex

Abstract

The Crimean-Congo Hemorrhagic Fever Virus (CCHFV) is a tripartite negative-strand RNA virus (NSRV) capable of causing severe hemorrhagic fever within humans. The segmented RNA genome of CCHFV does not exist as naked RNA, but is instead completely encapsidated by a nucleocapsid protein (NP). Very little is known about the molecular mechanism underlying viral NP–RNA encapsidation among the Bunyaviridae. This thesis demonstrates that the CCHFV NP exists as a monomer in solution, an unusual characteristic among NSRVs, even in the absence of RNA. Molecular interactions between recombinant CCHFV NP and ssRNA/dsRNA versions of the short 5’–3’ panhandle formed by the small (S) segment of the CCHFV genome were analyzed by gel electrophoresis mobility shift assays (EMSA) and demonstrated that CCHFV NP failed to bind to the ssRNA version of the short 5’–3’ panhandle structure. This thesis research provides the basis for a broader understanding of the CCHFV NP structure, mechanisms behind RNA encapsidation and the molecular basis of interaction between the short 5’–3’ RNA S-segment panhandle and CCHFV NP.