Characterization of herpes simplex virus 1 alpha proteins 0, 4, and 27 with monoclonal antibodies

Analyses of the reactivity and patterns of synthesis of infected cell polypeptides (ICPs) specified by herpes simplex virus (HSV) 1 and 2 and by HSV-1 X HSV-2 recombinants indicated that monoclonal antibody H1183 reacted with HSV-1 alpha ICP0, whereas monoclonal antibody H1113 reacted with both HSV-1 and HSV-2 alpha ICP27. H1083 and H1113 and a monoclonal antibody to ICP4 (H640) similar to one previously described (D. K. Braun et al., J. Virol. 46:103-112.) were then used to study the properties of these alpha proteins. The results were as follows: alpha ICP0, ICP4, and ICP27 accumulated primarily in the nuclei of infected cells. ICP4 and ICP27 were poorly soluble in nondenaturing buffer solutions. ICP0 was considerably more soluble than ICP4 and ICP27. ICP0, ICP4, and ICP27 were readily partially purified by immunoaffinity chromatography from lysates of infected cells solubilized with denaturing agents such as sodium dodecyl sulfate. ICP0 and ICP27 were phosphorylated in cells overlaid with medium containing 32P early (1 to 3 h) or late (18 to 20 h) postinfection. A fraction, but not all, 32P that was incorporated early was chased in the presence of unlabeled phosphate. ICP0, ICP4, and ICP27 labeled with either 32P or [35S]methionine yielded multiple spots upon two-dimensional separations. However, ICP4 quantitatively precipitated at the origin when the migration in the first dimension was from acid to base, and both ICP4 and ICP27 partially precipitated at the origin when the direction of migration was reversed.