Table 1.
| Nonstructural Protein (nsp) | Function |
|---|---|
| nsp 1 | Promotes cellular mRNA degradation and blocks host cell translation, results in blocking innate immune response |
| nsp 2 | No known function, binds to prohibitin proteins |
| nsp 3 | Large, multi-domain transmembrane protein, activities include: • Ubl1 and Ac domains, interact with N protein • ADRP activity, promotes cytokine expression • PLPro/Deubiquitinase domain, cleaves viral polyprotein and blocks host innate immune response • Ubl2, NAB, G2M, SUD, Y domains, unknown functions |
| nsp 4 | Potential transmembrane scaffold protein, important for proper structure of DMVs |
| nsp 5 | Mpro, cleaves viral polyprotein |
| nsp 6 | Potential transmembrane scaffold protein |
| nsp 7 | Forms hexadecameric complex with nsp8, may act as processivity clamp for RNA polymerase |
| nsp 8 | Forms hexadecameric complex with nsp7, may act as processivity clamp for RNA polymerase; may act as primase |
| nsp 9 | RNA binding protein phosphatase |
| nsp 10 | Cofactor for nsp16 and nsp14, forms heterodimer with both and stimulates ExoN and 2-O-MT activity |
| nsp 12 | Replication enzyme (RNA-dependent RNA polymerase) |
| nsp 13 | RNA helicase, 5′ triphosphatase |
| nsp 14 | N7 MTase and 3′–5′ exoribonuclease, ExoN; N7 MTase adds 5′ cap to viral RNAs, ExoN activity is important for proofreading of viral genome |
| nsp 15 | Viral endoribonuclease, NendoU |
| nsp 16 | 2′-O-MT; shields viral RNA from MDA5 recognition |