Ultrastructural analysis of the effect of p32 on HSV-1 nuclear egress. sh-Luc-HEp-2 (A) and sh-p32-HEp-2 cells (B) infected with wild-type HSV-1(F) at an MOI of 5 were fixed at 24 h postinfection, embedded, sectioned, stained, and examined by transmission electron microscopy. (B-a and B-b) Higher magnifications of the corresponding boxed areas in panel B showing invagination structures containing primary enveloped virions. Nu, nucleus; Cy, cytoplasm; NM, nuclear membrane.