title: Effect of specific amino acid substitutions in the putative fusion peptide of structural glycoprotein E2 on Classical Swine Fever Virus replication.
abstract: E2, along with E(rns) and E1, is an envelope glycoprotein of Classical Swine Fever Virus (CSFV). E2 is involved in several virus functions: cell attachment, host range susceptibility and virulence in natural hosts. Here we evaluate the role of a specific E2 region, (818)CPIGWTGVIEC(828), containing a putative fusion peptide (FP) sequence. Reverse genetics utilizing a full-length infectious clone of the highly virulent CSFV strain Brescia (BICv) was used to evaluate how individual amino acid substitutions within this region of E2 may affect replication of BICv. A synthetic peptide representing the complete E2 FP amino acid sequence adopted a β-type extended conformation in membrane mimetics, penetrated into model membranes, and perturbed lipid bilayer integrity in vitro. Similar peptides harboring amino acid substitutions adopted comparable conformations but exhibited different membrane activities. Therefore, a preliminary characterization of the putative FP (818)CPIGWTGVIEC(828) indicates a membrane fusion activity and a critical role in virus replication.
authors.affiliation: Plum Island Animal Disease Center, ARS, USDA, USA.
authors.forename: I J
authors.initials: IJ
authors.lastname: Fernández-Sainz
authors.affiliation: Biophysics Unit (CSIC-UPV/EHU), Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Largo
authors.affiliation: Plum Island Animal Disease Center, ARS, USDA, USA.
authors.forename: D P
authors.initials: DP
authors.lastname: Gladue
authors.affiliation: Plum Island Animal Disease Center, ARS, USDA, USA.
authors.forename: P
authors.initials: P
authors.lastname: Fletcher
authors.affiliation: Plum Island Animal Disease Center, ARS, USDA, USA; Plum Island Animal Disease Center, DHS, Greenport, NY 11944, USA.
authors.forename: V
authors.initials: V
authors.lastname: O'Donnell
authors.affiliation: Plum Island Animal Disease Center, ARS, USDA, USA.
authors.forename: L G
authors.initials: LG
authors.lastname: Holinka
authors.affiliation: Department of Experimental and Health Sciences, Universitat Pompeu Fabra (UPF), E-08003 Barcelona, Spain.
authors.forename: L B
authors.initials: LB
authors.lastname: Carey
authors.affiliation: Plum Island Animal Disease Center, DHS, Greenport, NY 11944, USA.
authors.forename: X
authors.initials: X
authors.lastname: Lu
authors.affiliation: Biophysics Unit (CSIC-UPV/EHU), Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: J L
authors.initials: JL
authors.lastname: Nieva
authors.affiliation: Plum Island Animal Disease Center, ARS, USDA, USA. Electronic address: manuel.borca@ars.usda.gov.
authors.forename: M V
authors.initials: MV
authors.lastname: Borca
mesh_terms: D019943:Amino Acid Substitution; D000818:Animals; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D006692:Classical Swine Fever Virus / Q000235:genetics / Q000502:physiology*; D008081:Liposomes / Q000378:metabolism; D008958:Models, Molecular; D050505:Mutant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011487:Protein Conformation; D059386:Reverse Genetics; D013552:Swine; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D053586:Virus Internalization
chemical_list: D008081:Liposomes; D050505:Mutant Proteins; D014759:Viral Envelope Proteins; C087086:glycoprotein E2, classical swine fever virus
keywords: CSFV; Classical Swine Fever Virus; Classical swine fever; Fusion peptide; Pestivirus