Evidence for the presence of a low-level, persistent baculovirus infection of Mamestra brassicae insects.
A laboratory culture of Mamestra brassicae insects (MbLC) harbours a latent or occult baculovirus that resembles M. brassicae multiple nucleocapsid nucleopolyhedrovirus (MbMNPV). Although conventional extraction techniques have failed to detect the presence of virus in MbLC, control virus-free insects (MbWS) died of an MbMNPV-like infection after being fed MbLC fat-body cells. This suggested that the MbLC cells harboured infectious MbMNPV, albeit at low levels. We have also demonstrated that fat-body cells from MbLC, but not from MbWS, contain mRNA specific for the polyhedrin gene and transcriptional factors that are capable of activating baculovirus late and very late gene promoters linked to a reporter gene encoding chloramphenicol acetyltransferase. Our data provide indirect evidence that the latent MbMNPV in the MbLC insects is maintained as a persistent infection, with the expression of viral genes at a low level.
Hughes
D S
DS
School of Biological and Molecular Sciences, Oxford Brookes University, UK.
Possee
R D
RD
King
L A
LA
D000818:Animals; D015139:Blotting, Southern; D004279:DNA, Viral; D009036:Moths / Q000821:virology*; D017924:Nucleopolyhedroviruses / Q000235:genetics / Q000502:physiology*; D000077183:Occlusion Body Matrix Proteins; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger; D014764:Viral Proteins / Q000235:genetics; D015678:Viral Structural Proteins; D017735:Virus Latency
D004279:DNA, Viral; D000077183:Occlusion Body Matrix Proteins; D012333:RNA, Messenger; D014764:Viral Proteins; D015678:Viral Structural Proteins; C009829:polyhedrin protein, Nucleopolyhedrovirus