PROSITE documentation PDOC51493
Arterivirus nsp4 proteinase domain profile


Arteriviruses are enveloped, positive-stranded RNA viruses and include pathogens of major economic concern to the swine- and horse-breeding industries [E1]:

  - Equine arteritis virus (EAV).
  - Porcine reproductive and respiratory syndrome virus (PRRSV).
  - Mice actate dehydrogenase-elevating virus.
  - Simian hemorrhagic fever virus.

The arterivirus replicase gene encodes two large precursor polyproteins that are processed by the viral main proteinase nonstructural protein 4 (nsp4). The structure of the enzyme reveals two chymotrypsin-like antiparallel β-barrels and an extra C-terminal α/β domain that may play a role in mediating protein-protein interactions (see <PDB:1MBM; A>). The N-terminal barrel consists of six β-strands (A1 to F1), while the C-terminal barrel is composed of seven (A2 to G2). The core of both β-barrels is comprised of conserved hydrophobic residues. The additional C-terminal domain consists of two pairs of short antiparallel β-sheets and two α-helices. It interacts with the C-terminal barrel through an interface consisting of conserved hydrophobic residues. A canonical catalytic triad that is composed of Ser, His, and Asp is located in the open cleft between the β-barrels domain [1,2]. The nsp4 proteinase domain forms peptidase family S32 [E2].

The profile we developed covers the entire nsp4 proteinase domain.

Last update:

May 2010 / First entry.


Technical section

PROSITE method (with tools and information) covered by this documentation:

AV_NSP4_PRO, PS51493; Arterivirus nsp4 proteinase domain profile  (MATRIX)


1AuthorsBarrette-Ng I.H. Ng K.K.S. Mark B.L. van Aken D. Cherney M.M. Garen C. Kolodenko Y. Gorbalenya A.E. Snijder E.J. James M.N.G.
TitleStructure of arterivirus nsp4. The smallest chymotrypsin-like proteinase with an alpha/beta C-terminal extension and alternate conformations of the oxyanion hole.
SourceJ. Biol. Chem. 277:39960-39966(2002).
PubMed ID12163505

2AuthorsTian X. Lu G. Gao F. Peng H. Feng Y. Ma G. Bartlam M. Tian K. Yan J. Hilgenfeld R. Gao G.F.
TitleStructure and cleavage specificity of the chymotrypsin-like serine protease (3CLSP/nsp4) of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV).
SourceJ. Mol. Biol. 392:977-993(2009).
PubMed ID19646449



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