title: Virus progeny of murine cytomegalovirus bacterial artificial chromosome pSM3fr show reduced growth in salivary Glands due to a fixed mutation of MCK-2.
abstract: Murine cytomegalovirus (MCMV) Smith strain has been cloned as a bacterial artificial chromosome (BAC) named pSM3fr and used for analysis of virus gene functions in vitro and in vivo. When sequencing the complete BAC genome, we identified a frameshift mutation within the open reading frame (ORF) encoding MCMV chemokine homologue MCK-2. This mutation would result in a truncated MCK-2 protein. When mice were infected with pSM3fr-derived virus, we observed reduced virus production in salivary glands, which could be reverted by repair of the frameshift mutation. When looking for the source of the mutation, we consistently found that virus stocks of cell culture-passaged MCMV Smith strain are mixtures of viruses with or without the MCK-2 mutation. We conclude that the MCK-2 mutation in the pSM3fr BAC is the result of clonal selection during the BAC cloning procedure.
authors.affiliation: Max von Pettenkofer Institute, Lehrstuhl Virologie, Feodor-Lynen-Strasse 25, München, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Jordan
authors.forename: Johannes
authors.initials: J
authors.lastname: Krause
authors.forename: Adrian
authors.initials: A
authors.lastname: Prager
authors.forename: Maja
authors.initials: M
authors.lastname: Mitrovic
authors.forename: Stipan
authors.initials: S
authors.lastname: Jonjic
authors.forename: Ulrich H
authors.initials: UH
authors.lastname: Koszinowski
authors.forename: Barbara
authors.initials: B
authors.lastname: Adler
mesh_terms: D000818:Animals; D019742:Chemokines, CC / Q000235:genetics* / Q000378:metabolism*; D022202:Chromosomes, Artificial, Bacterial; D005260:Female; D016368:Frameshift Mutation; D051379:Mice; D008807:Mice, Inbred BALB C; D018146:Muromegalovirus / Q000235:genetics* / Q000472:pathogenicity*; D012469:Salivary Glands / Q000821:virology*; D017384:Sequence Deletion; D019562:Viral Load; D014764:Viral Proteins / Q000235:genetics* / Q000378:metabolism*; D014774:Virulence
chemical_list: D019742:Chemokines, CC; C121663:MCK-2 protein, Mouse cytomegalovirus 1; D014764:Viral Proteins