Identification and characterization of a 50K DNA-binding protein of guinea-pig cytomegalovirus.
In a previous study we showed that cells infected with guinea-pig cytomegalovirus (GPCMV) contain large amounts of a non-structural 50K nuclear protein that is detectable by immunoelectron microscopy using monoclonal antibodies. The present study shows that this 50K protein is a DNA-binding protein, as determined by single-stranded DNA affinity chromatography, and a phosphorylated protein as demonstrated by immunoprecipitation using [32P]orthophosphate-labelled cells. This protein binds both viral and host cellular double-stranded and single-stranded DNA, assayed by a simple method using DNA linked to a nylon membrane. Induction of the 50K protein in GPCMV-infected cells was highly dependent on viral DNA synthesis, which was detected by dot hybridization using a cloned GPCMV DNA probe. Synthesis of the 50K protein was significantly impaired when phosphonoacetic acid was added to the culture medium. Induction of the 50K protein was detected about 6 h before the appearance of the 76K viral matrix protein.
Nogami-Satake
T
T
Institute for Developmental Research, Aichi Prefectural Colony, Japan.
Tsutsui
Y
Y
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D011232:Chemical Precipitation; D003587:Cytomegalovirus / Q000032:analysis*; D004279:DNA, Viral / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000032:analysis*; D005455:Fluorescent Antibody Technique; D006168:Guinea Pigs; D008970:Molecular Weight; D009687:Nuclear Proteins / Q000032:analysis*; D010750:Phosphoproteins / Q000032:analysis* / Q000378:metabolism; D014764:Viral Proteins / Q000032:analysis*
D000911:Antibodies, Monoclonal; D004279:DNA, Viral; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D014764:Viral Proteins