PMID- 20668084
OWN - NLM
STAT- MEDLINE
DCOM- 20100928
LR  - 20211020
IS  - 1098-5514 (Electronic)
IS  - 0022-538X (Print)
IS  - 0022-538X (Linking)
VI  - 84
IP  - 19
DP  - 2010 Oct
TI  - Proteolytic products of the porcine reproductive and respiratory syndrome virus 
      nsp2 replicase protein.
PG  - 10102-12
LID - 10.1128/JVI.01208-10 [doi]
AB  - The nsp2 replicase protein of porcine reproductive and respiratory syndrome virus 
      (PRRSV) was recently demonstrated to be processed from its precursor by the PL2 
      protease at or near the G(1196)|G(1197) dipeptide in transfected CHO cells. Here 
      the proteolytic cleavage of PRRSV nsp2 was further investigated in virally 
      infected MARC-145 cells by using two recombinant PRRSVs expressing epitope-tagged 
      nsp2. The data revealed that PRRSV nsp2 exists as different isoforms, termed 
      nsp2a, nsp2b, nsp2c, nsp2d, nsp2e, and nsp2f, during PRRSV infection. Moreover, 
      on the basis of deletion mutagenesis and antibody probing, these nsp2 species 
      appeared to share the same N terminus but to differ in their C termini. The 
      largest protein, nsp2a, corresponded to the nsp2 product identified in 
      transfected CHO cells. nsp2b and nsp2c were processed within or near the 
      transmembrane (TM) region, presumably at or near the conserved sites 
      G(981)|G(982) and G(828)|G(829)|G(830), respectively. The C termini for nsp2d, 
      -e, and -f were mapped within the nsp2 middle hypervariable region, but no 
      conserved cleavage sites could be definitively predicted. The larger nsp2 species 
      emerged almost simultaneously in the early stage of PRRSV infection. Pulse-chase 
      analysis revealed that all six nsp2 species were relatively stable and had low 
      turnover rates. Deletion mutagenesis revealed that the smaller nsp2 species 
      (e.g., nsp2d, nsp2e, and nsp2f) were not essential for viral replication in cell 
      culture. Lastly, we identified a cellular chaperone, named heat shock 70-kDa 
      protein 5 (HSPA5), that was strongly associated with nsp2, which may have 
      important implications for PRRSV replication. Overall, these findings indicate 
      that PRRSV nsp2 is increasingly emerging as a multifunctional protein and may 
      have a profound impact on PRRSV replication and viral pathogenesis.
FAU - Han, Jun
AU  - Han J
AD  - Department of Veterinary and Biomedical Sciences, University of Minnesota, Saint 
      Paul, Minnesota 55108, USA.
FAU - Rutherford, Mark S
AU  - Rutherford MS
FAU - Faaberg, Kay S
AU  - Faaberg KS
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20100728
PL  - United States
TA  - J Virol
JT  - Journal of virology
JID - 0113724
RN  - 0 (DNA, Viral)
RN  - 0 (Isoenzymes)
RN  - 0 (Recombinant Proteins)
RN  - 0 (Viral Proteins)
RN  - EC 2.7.7.48 (RNA-Dependent RNA Polymerase)
RN  - EC 3.4.- (Peptide Hydrolases)
SB  - IM
MH  - Animals
MH  - Base Sequence
MH  - CHO Cells
MH  - Cricetinae
MH  - Cricetulus
MH  - DNA, Viral/genetics
MH  - Enzyme Stability
MH  - Isoenzymes/chemistry/genetics/metabolism
MH  - Peptide Hydrolases/metabolism
MH  - Porcine respiratory and reproductive syndrome 
      virus/*enzymology/genetics/physiology
MH  - Protein Processing, Post-Translational
MH  - RNA-Dependent RNA Polymerase/chemistry/genetics/*metabolism
MH  - Recombinant Proteins/chemistry/genetics/metabolism
MH  - Sequence Deletion
MH  - Swine
MH  - Transfection
MH  - Viral Proteins/chemistry/genetics/*metabolism
MH  - Virus Replication
PMC - PMC2937792
EDAT- 2010/07/30 06:00
MHDA- 2010/09/30 06:00
PMCR- 2011/04/01
CRDT- 2010/07/30 06:00
PHST- 2010/07/30 06:00 [entrez]
PHST- 2010/07/30 06:00 [pubmed]
PHST- 2010/09/30 06:00 [medline]
PHST- 2011/04/01 00:00 [pmc-release]
AID - JVI.01208-10 [pii]
AID - 1208-10 [pii]
AID - 10.1128/JVI.01208-10 [doi]
PST - ppublish
SO  - J Virol. 2010 Oct;84(19):10102-12. doi: 10.1128/JVI.01208-10. Epub 2010 Jul 28.