Early Nuclear Antigen As DNA-binding Protein in Cytomegalovirus-infected Cells

Early nuclear complement-fixing antigen in cytomegalovirus (CMV) (strain Ad 169)-infected human embryonic fibroblasts is described. The nuclear antigen was solubilized from CMV-infected cells by high salt treatment. DNA-binding properties were studied by DNA-cellulose chromatography. The purified antigen, eluted from double-stranded DNA-cellulose columns, was added to acid-fixed nuclear preparations from human embryonic fibroblasts and then exposed to human sera containing antibodies to CMV. Positive staining was obtained by anti-complement immunofluorescence. These data identify the CMV-determined nuclear antigen as a DNA-binding protein. In this respect, it is similar to the Epstein-Barr virus nuclear antigen.