HUMAN CORONAVIRUS NL63 NUCLEOPROTEIN
Human Coronavirus NL63 Nucleoprotein is a recombinant protein containing the nucleocapsid C-terminal region (130 amino acids), cloned and expressed in E. coli, and purified by affinity chromatography (nickel column) with greater than 95% purity.
Coronaviruses are species of virus belonging to the subfamily Coronavirinae in the family Coronaviridae, in the order Nidovirales. They are enveloped viruses with positive-stranded, capped, and polyadenylated RNA genomes ranging in size from 28 to 32 kb. Human coronavirus NL63 (HCoV-NL63) is a species of Alphacoronavirus that was identified in late 2004 in a seven-month-old child with bronchiolitis in the Netherlands. Infection with the virus has been confirmed worldwide, and has an association with many common symptoms and diseases. Associated diseases include mild to moderate upper respiratory tract infections, severe lower respiratory tract infection, croup and bronchiolitis. The virus is found primarily in young children, the elderly, and immunocompromised patients with acute respiratory illness. It also has a seasonal association in temperate climates.
During virus replication, a variety of proteins are synthesised including the viral RNA binding protein, nucleoprotein (N or nucleocapsid protein), a multi-functional protein with roles in both the virus life cycle and modulating host cell function. One of the key functions of the N protein is to bind viral RNA and selectively incorporate it into virus particles. The genome RNA is complexed with the basic nucleocapsid (N) protein to form a helical capsid found within the viral membrane. The nucleocapsid proteins of coronaviruses representing groups I, II, and III have been shown to localize to the nucleolus as well as to the cytoplasm suggesting that N protein induces a cell cycle delay or arrest, most likely in the G2/M phase, possibly by inhibition of cytokines (Weiss and Navas-Martin, 2005).