Table 1.
Non-structural proteins of Equine arteritis virus (EAV)a
| Protein | sizeb | mode of expressionc | (putative) function(s) |
|---|---|---|---|
| nsp1d | 260 | TI + nsp1 PCP | proteinase (PCP), mononuclear zinc finger, role in sgRNA synthesis |
| nsp2 | 571 | TI + nsp1 PCP + nsp2 CP | proteinase (CP), integral membrane protein, replication complex formation |
| nsp3 | 233 | TI + nsp2 CP + nsp4 SP | integral membrane protein, replication complex formation |
| nsp4 | 204 | TI + nsp4 SP | main proteinase (SP) |
| nsp5 | 162 | TI + nsp4 SP | integral membrane protein |
| nsp6 | 22 | TI + nsp4 SP | ? |
| nsp7 | 225 | TI + nsp4 SP | ? |
| nsp8e | 50 | TI + nsp4 SP + TT | ? |
| nsp9 | 693 | TI + RFS + nsp4 SP | RdRp |
| nsp10 | 467 | TI + RFS + nsp4 SP | RNA helicase/NTPase, polynuclear zinc finger, role in sgRNA synthesis |
| nsp11 | 219 | TI + RFS + nsp4 SP | nidovirus-specific endoribonuclease |
| nsp12 | 119 | TI + RFS + nsp4 SP + TT | ? |
a
Based on the currently known replicase processing scheme of EAV
b
in aa
c
TI, translation initiation; RFS, ORF1a/ORF1b ribosomal frameshifting; TT, translation termination; PCP, nsp1 cysteine proteinase; CP, nsp2 cysteine proteinase; SP, nsp4 serine proteinase
d
Nsp1 of LDV and PRRSV is cleaved internally by an additional papain-like proteinase to yield nsp1α and nsp1β
e
Due to ribosomal frameshifting, nsp8 is identical to the N-terminal 50 aa of nsp9