Immunoblot detection of the HSV-1 protein UL1, UL2, UL3, or UL4 in electrophoretically separated RS cell lysates. Lysates of uninfected RS cells (Mock; lane 1) or RS cells, infected at an MOI of 10 with the indicated virus, were separated by SDS-polyacrylamide gel electrophoresis, transferred to nitrocellulose, and probed with antiserum to UL3 (A), UL2 (B), UL1 (C), or UL4 (D). RS cells were harvested 18 to 24 hpi. Approximately 2 × 105 (A and B) and 7 × 104 (C and D) infected cells were loaded per lane.