FIG. 6.

(A) Individual plaque-purified tk−:Δ34.5 isolates that express the Us11 polypeptide are capable of enhanced protein synthesis. Nonpermissive U373 cells were infected with the individual viral isolates at high MOI. Proteins labeled in a 1-h pulse with [³⁵S]methionine at 13 h postinfection were fractionated by SDS-PAGE and visualized by autoradiography. The positions of molecular size markers (in kilodaltons) are indicated to the right of the gel. (B) Analysis of steady-state Us11 levels in SUP1 versus Δ34.5 tk−:11S. S10 extracts were prepared from infected U373 cells as described in Materials and Methods. Aliquots were fractionated by SDS-PAGE, electroblotted to Immobilon, and probed with a monoclonal antibody against HSV-1 Us11 (44). Identical results were obtained with extracts prepared directly in 1× Laemmli buffer (not shown).