title: Profiling of cellular proteins in porcine reproductive and respiratory syndrome virus virions by proteomics analysis.
abstract: BACKGROUND
  Porcine reproductive and respiratory syndrome virus (PRRSV) is an enveloped virus, bearing severe economic consequences to the swine industry worldwide. Previous studies on enveloped viruses have shown that many incorporated cellular proteins associated with the virion's membranes that might play important roles in viral infectivity. In this study, we sought to proteomically profile the cellular proteins incorporated into or associated with the virions of a highly virulent PRRSV strain GDBY1, and to provide foundation for further investigations on the roles of incorporated/associated cellular proteins on PRRSV's infectivity.
  
  
  RESULTS
  In our experiment, sixty one cellular proteins were identified in highly purified PRRSV virions by two-dimensional gel electrophoresis coupled with mass spectrometric approaches. The identified cellular proteins could be grouped into eight functional categories including cytoskeletal proteins, chaperones, macromolecular biosynthesis proteins, metabolism-associated proteins, calcium-dependent membrane-binding proteins and other functional proteins. Among the identified proteins, four have not yet been reported in other studied envelope viruses, namely, guanine nucleotide-binding proteins, tyrosine 3-monooxygenase/tryptophan 5-monooxygenase, peroxiredoxin 1 and galectin-1 protein. The presence of five selected cellular proteins (i.e., β-actin, Tubulin, Annexin A2, heat shock protein Hsp27, and calcium binding proteins S100) in the highly purified PRRSV virions was validated by Western blot and immunogold labeling assays.
  
  
  CONCLUSIONS
  Taken together, the present study has demonstrated the incorporation of cellular proteins in PRRSV virions, which provides valuable information for the further investigations for the effects of individual cellular proteins on the viral replication, assembly, and pathogenesis.
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China.
authors.forename: Chengwen
authors.initials: C
authors.lastname: Zhang
authors.forename: Chunyi
authors.initials: C
authors.lastname: Xue
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Qingming
authors.initials: Q
authors.lastname: Kong
authors.forename: Xiangpeng
authors.initials: X
authors.lastname: Ren
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Li
authors.forename: Dingming
authors.initials: D
authors.lastname: Shu
authors.forename: Yingzuo
authors.initials: Y
authors.lastname: Bi
authors.forename: Yongchang
authors.initials: Y
authors.lastname: Cao
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002460:Cell Line; D002522:Chlorocebus aethiops; D015180:Electrophoresis, Gel, Two-Dimensional; D016253:Microscopy, Immunoelectron; D019316:Porcine respiratory and reproductive syndrome virus / Q000737:chemistry* / Q000302:isolation & purification*; D011506:Proteins / Q000032:analysis*; D020543:Proteome / Q000032:analysis*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014771:Virion / Q000737:chemistry* / Q000302:isolation & purification*
chemical_list: D011506:Proteins; D020543:Proteome