title: Pore-forming activity of pestivirus p7 in a minimal model system supports genus-specific viroporin function.
abstract: Viroporins are small integral membrane proteins functional in viral assembly and egress by promoting permeabilization. Blocking of viroporin function therefore constitutes a target for antiviral development. Classical swine fever virus (CSFV) protein p7 has been recently regarded as a class II viroporin. Here, we sought to establish the determinants of the CSFV p7 permeabilizing activity in a minimal model system. Assessment of an overlapping peptide library mapped the porating domain to the C-terminal hydrophobic stretch (residues 39-67). Pore-opening dependence on pH or sensitivity to channel blockers observed for the full protein required the inclusion of a preceding polar sequence (residues 33-38). Effects of lipid composition and structural data further support that the resulting peptide (residues 33-67), may comprise a bona fide surrogate to assay p7 activity in model membranes. Our observations imply that CSFV p7 relies on genus-specific structures-mechanisms to perform its viroporin function.
authors.affiliation: Biophysics Unit (CSIC-UPV/EHU) and Biochemistry and Molecular Biology Department, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: Eneko
authors.initials: E
authors.lastname: Largo
authors.affiliation: Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA.
authors.forename: Douglas P
authors.initials: DP
authors.lastname: Gladue
authors.affiliation: Biophysics Unit (CSIC-UPV/EHU) and Biochemistry and Molecular Biology Department, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: Nerea
authors.initials: N
authors.lastname: Huarte
authors.affiliation: Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA.
authors.forename: Manuel V
authors.initials: MV
authors.lastname: Borca
authors.affiliation: Biophysics Unit (CSIC-UPV/EHU) and Biochemistry and Molecular Biology Department, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain. Electronic address: gbpniesj@lg.ehu.es.
authors.forename: José L
authors.initials: JL
authors.lastname: Nieva
mesh_terms: D000998:Antiviral Agents / Q000378:metabolism; D004252:DNA Mutational Analysis; D054884:Host-Pathogen Interactions; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008954:Models, Biological; D008958:Models, Molecular; D010576:Pestivirus / Q000235:genetics / Q000502:physiology*; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*; D019065:Virus Assembly; D057074:Virus Release
chemical_list: D000998:Antiviral Agents; D008565:Membrane Proteins; D014764:Viral Proteins
keywords: BVDV; CD; CL; CSFV; Channel blocker; Chol; Classical swine fever virus; HCV; PC; PE; PI; PS; Pestivirus; Pore-forming protein; SM; Viroporin; Viroporin inhibition; bovine viral diarrhea virus; cardiolipin; cholesterol; circular dichroism; classical swine fever virus; hepatitis C virus; phospahtidylethanolamine; phosphatidylcholine; phosphatidylinositol; phosphatidylserine; sphingomyelin