title: Isolation and partial characterization of nucleocapsid forms from cells infected with human cytomegalovirus strains AD169 and Towne.
abstract: We characterized nucleocapsid (NC) forms generated during infection with human cytomegalovirus (HCMV) strains AD169 and Towne. Two morphological forms of NC were isolated by Renografin-76 banding of the nuclear (N) or cytoplasmic (C) fractions of infected cells. SDS-PAGE analysis of the N- and C-NC forms of AD169 and Towne showed the presence of three polypeptides (150, 33, and 30 KD). The C-NC contained five additional polypeptides (260, 112, 110, 68, and 54 KD) with a counterpart in the mature virion. An additional polypeptide of 37 KD (Towne) or 39 KD (AD169) was only present in the B-NC and not in the A-NC, C-NC, or the mature virion. These polypeptides were basic as determined by two-dimensional PAGE analysis. The 37-KD (Towne) and the 39-KD (AD169) polypeptides were phosphorylated. The NC polypeptides were HCMV specific as shown by immunoprecipitation using a pool of HCMV-positive human antisera. The B-NC DNA was shown to have a restriction pattern identical to that of the infectious viral DNA, but no DNA was detected in the A-NC form. Analysis of NC forms by pulse-chase experiments identified a 'pre-NC' peak which may serve as a precursor to the A- and B-NC forms.
authors.affiliation: Department of Microbiology, School of Medicine, Georgetown University, Washington, D.C. 20007.
authors.forename: F
authors.initials: F
authors.lastname: Sedarati
authors.forename: L J
authors.initials: LJ
authors.lastname: Rosenthal
mesh_terms: D002213:Capsid / Q000302:isolation & purification*; D002478:Cells, Cultured; D003587:Cytomegalovirus / Q000254:growth & development; D003586:Cytomegalovirus Infections / Q000382:microbiology*; D004279:DNA, Viral / Q000302:isolation & purification; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D008854:Microscopy, Electron; D013045:Species Specificity; D014758:Viral Core Proteins / Q000302:isolation & purification*
chemical_list: D004279:DNA, Viral; D014758:Viral Core Proteins