title: Identification of two internal signal peptide sequences: critical for classical swine fever virus non-structural protein 2 to trans-localize to the endoplasmic reticulum.
abstract: BACKGROUND
  The membrane topology and molecular mechanisms for endoplasmic reticulum (ER) localization of classical swine fever virus (CSFV) non-structural 2 (NS2) protien is unclear. We attempted to elucidate the subcellular localization, and the molecular mechanisms responsible for the localization of this protein in our study. The NS2 gene was amplified by reverse transcription polymerase chain reaction, with the transmembrane region and hydrophilicity of the NS2 protein was predicted by bioinformatics analysis. Twelve cDNAs of the NS2 gene were amplified by the PCR deletion method and cloned into a eukaryotic expression vector, which was transfected into a swine umbilical vein endothelial cell line (SUVEC). Subcellular localization of the NS2 protein was characterized by confocal microscopy, and western blots were carried out to analyze protein expression.
  
  
  RESULTS
  Our results showed that the -NH2 terminal of the CSFV NS2 protein was highly hydrophobic and the protein localized in the ER. At least four transmembrane regions and two internal signal peptide sequences (amino acids103-138 and 220-262) were identified and thought to be critical for its trans-localization to the ER.
  
  
  CONCLUSIONS
  This is the first study to identify the internal signal peptide sequences of the CSFV NS2 protein and its subcellular localization, providing the foundation for further exploration of this protein's function of this protein and its role in CSFV pathogenesis.
authors: College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi, PR China.
authors: Kang-kang
authors: KK
authors: Guo
authors: Qing-hai
authors: QH
authors: Tang
authors: Yan-ming
authors: YM
authors: Zhang
authors: Kai
authors: K
authors: Kang
authors: Lei
authors: L
authors: He
references: Nature. 2006 Aug 17;442(7104):831-5
references: 16862121
references: PLoS Pathog. 2009 May;5(5):e1000403
references: 19412343
references: Mol Cells. 2007 Dec 31;24(3):358-63
references: 18182851
references: Curr Issues Mol Biol. 2007 Jan;9(1):63-9
references: 17263146
references: J Virol. 2007 Aug;81(16):8374-83
references: 17537845
references: Nat Rev Microbiol. 2008 Sep;6(9):699-708
references: 18587411
references: Nat Rev Microbiol. 2007 Jun;5(6):453-63
references: 17487147
references: Proc Natl Acad Sci U S A. 2006 Jan 31;103(5):1510-5
references: 16432213
references: J Virol. 1997 Sep;71(9):6373-80
references: 9261354
references: J Virol. 2000 Oct;74(20):9498-506
references: 11000219
references: J Virol. 2004 Mar;78(5):2414-25
references: 14963137
references: Proc Natl Acad Sci U S A. 2009 Mar 31;106(13):5342-7
references: 19282477
references: J Virol. 2004 Oct;78(19):10765-75
references: 15367643
references: Virol J. 2010 Jan 11;7:4
references: 20064240
references: Virus Res. 2006 Nov;121(2):134-43
references: 16797769
references: J Virol. 1996 Jun;70(6):4131-5
references: 8648755
references: J Biol Chem. 2002 Sep 6;277(36):33228-34
references: 12082096
references: Virology. 2007 Sep 1;365(2):376-89
references: 17482232