title: Open reading frame 5 of porcine reproductive and respiratory syndrome virus as a cause of virus-induced apoptosis.
abstract: The gene product of open reading frame 5 (p25) of porcine reproductive and respiratory syndrome (PRRS) virus has been expressed by coinfection of culture cells with vaccinia virus expressing the T7 RNA polymerase and a recombinant vaccinia virus encoding the open reading frame 5 gene under the T7 promoter and the encephalomyocarditis virus internal ribosome entry site. In spite of the reported efficiency of the expression system, very poor accumulation of p25 protein was observed and a strong cytotoxicity was produced in the doubly infected cells. This cell toxicity was shown to occur by induction of apoptosis, as indicated by nucleosome ladder formation, chromatin condensation, and rRNA degradation. Apoptosis induction was also observed after infection of cultured cells with an adapted PRRS virus strain and after infection of swine macrophage cells with a PRRS virus field strain. Contrary to the observations made for other cases of virus-induced apoptosis, we could not prevent p25 protein-induced apoptosis by using a cell line permanently expressing Bcl-2 protein.
authors.affiliation: Centro Nacional de Biotecnologiá, Madrid, Spain.
authors.forename: P
authors.initials: P
authors.lastname: Suárez
authors.forename: M
authors.initials: M
authors.lastname: Díaz-Guerra
authors.forename: C
authors.initials: C
authors.lastname: Prieto
authors.forename: M
authors.initials: M
authors.lastname: Esteban
authors.forename: J M
authors.initials: JM
authors.lastname: Castro
authors.forename: A
authors.initials: A
authors.lastname: Nieto
authors.forename: J
authors.initials: J
authors.lastname: Ortín
mesh_terms: D000818:Animals; D017209:Apoptosis; D018018:Arterivirus / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D001483:Base Sequence; D002460:Cell Line; D002522:Chlorocebus aethiops; D003001:Cloning, Molecular; D004279:DNA, Viral / Q000032:analysis; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010957:Plasmids; D012367:RNA, Viral / Q000096:biosynthesis / Q000302:isolation & purification; D015183:Restriction Mapping; D013030:Spain; D013552:Swine; D013553:Swine Diseases / Q000821:virology*; D013577:Syndrome; D014616:Vaccinia virus; D014759:Viral Envelope Proteins; D014764:Viral Proteins / Q000096:biosynthesis*
chemical_list: D004279:DNA, Viral; D012367:RNA, Viral; D014759:Viral Envelope Proteins; D014764:Viral Proteins; C114789:glycoprotein 5, PRRSV