Structures of nairovirus-encoded NPs. Structures of CCHFV NP (PDB accession number 3U3I) (A), HAZV NP (B), KUPV NP (C), and ERVEV NP (D) are shown in cartoon diagrams (left) and covered by electrostatic potentials of the surfaces (right). In the cartoon diagrams, the head domains and stalk domains are colored in pale green and blue, respectively. (E) Structural alignment of four nairovirus-encoded NPs. The CCHFV, HAZV, KUPV (a and b chains), and ERVEV NPs are displayed as ribbon diagrams and colored blue, red, gold/brown, and green, respectively. These four structures are shown with superimposed head domains.