Measles is an acute contagious disease characterized by high fever and a maculopapular rash. Measles virus (MV), the causative agent, is an enveloped virus classified as a member of the genus Morbillivirus in the family Paramyxoviridae. The virus has a nonsegmented negative-sense RNA genome, which contains six genes encoding single structural proteins, designated the nucleocapsid (N), phospho-(P), matrix (M), fusion (F), hemagglutinin (H), and large (L) proteins. The genome is encapsidated by the N protein and forms a nucleocapsid that exhibits helical symmetry. The amino-terminal region of the N protein (NCORE; amino acids 1 to 400) constitutes the core region of the helical nucleocapsid while the remaining carboxyl-terminal region (NTAIL; aa 401 to 525) is intrinsically disordered and located outside of the helical nucleocapsid core.