Figure 2.

Viral nucleocapsid proteins (NCs) function in several stages of the virus life cycle. After virus entry into the cell, inclusion bodies (IBs) were formed to be the center of transcription and replication, and the NC was one of indispensable partners of IBs. NCs package the viral RNA, to protect the viral RNA from digestion by RNase, and together with other viral components into viral particles, which then mature and yield. (a) NC of coronavirus can be phosphorylated by Glycogen synthase kinase‐3 (GSK3), which enhance the interaction of NC and DDX1 to facilitate template switching from discontinuous to continuous transcription for producing longer sgmRNAs and genome RNAs (gRNAs); (b) NCs package the viral RNA and associate with other viral proteins to form viral replication ‘factory’; (c) Hepatitis C virus (HCV) core protein interacts with the μ subunit of clathrin adaptor protein complex 2 (AP2M1) which is phosphorylated by AP2 associated kinase 1 (AAK1) and cyclin G associated kinase (GAK), and dephosphorylated by Phosphatase 2A (PP2A), and phosphorylated AP2M1 helps NC for assembly; diacylglycerol acyltransferase 1 (DGAT1) can recruit core protein to lipid droplets to facilitate the interaction of core with HCV non‐structural protein 5A (NS5A) protein; mitogen‐activated protein kinase‐activated protein kinase 3 (MAPKAPK3) increased HCV internal ribosome entry site (IRES)‐mediated translation and this activity was further enhanced by core protein; (d) NCs interact with M protein and cdE2 to facilitate the viral budding.