Recombinant Measles virus Nucleoprotein (N), partial

Function

Forms the helical nucleocapsid (NC) in a ratio of 1 N per 6 ribonucleotides, protecting the genome from nucleases (By similarity). The nucleocapsid (NC) has a helical structure with either 12.35 or 11.64 N per turn, approximately 20 nm in diameter, with a hollow central cavity approximately 5 nm in diameter (By similarity). The encapsidated genomic RNA serves as template for transcription and replication; encapsidation by N is coupled to RNA synthesis (By similarity). Forms the encapsidation complex with the phosphoprotein protein P (By similarity). Before encapsidation, the newly synthesized free N protein, so-called N0, is chaperoned by P (By similarity). Participates, together with P, in the formation of viral factories (viroplasms), which are large inclusions in the host cytoplasm where replication takes place (By similarity). N is released in the blood following lysis of measles infected cells, it interacts then with human FCGR2B on immune cells, inducing apoptosis and blocking inflammatory immune response (By similarity)

Subcellular Location

Virion; Host cytoplasm; Host nucleus

Subunit

Homomultimer; forms the nucleocapsid (By similarity). Binds to viral genomic RNA (By similarity). N0 interacts (via Ncore) with the phosphoprotein (via N-terminus); this interaction allows P to chaperon N0 to avoid N polymerization and non-specific RNA binding before encapsidation (By similarity). Interacts (via the Ntail) as N-RNA template with the phosphoprotein (via C-terminus XD); this interaction maintains the P/L complex anchored to the nucleocapsid template during the sequential transcription (By similarity). Interacts with the phosphoprotein; this interaction leads to the formation of membraneless organelles that function as viral replication factories (By similarity). Interacts with human FCGR2B protein (By similarity). Interacts with human PPIA/CYPA and PPIB/CYPB (By similarity)

• Rota J.S. et al. Comparison of sequences of the H, F, and N coding genes of measles virus vaccine strains. — Virus Res. (1994)
• Herschke F. et al. Heterogeneity of the interferon a/b response to measles infection governed by genome sequence, host cell type, dendritic cell maturation state and donors. (DEC-)
• Tillieux S.L. et al. Comparative analysis of the complete nucleotide sequences of measles, mumps, and rubella strain genomes contained in Priorix-Tetra and ProQuad live attenuated combined vaccines. — Vaccine (2009)
• Parks C.L. et al. Comparison of predicted amino acid sequences of measles virus strains in the Edmonston vaccine lineage. — J. Virol. (2001)