Effect of HSV infection on ICP0 promoter-derived luciferase activities. (A) Graphical representation of the nucleotide sequences of the ICP0 promoter region from position -834 to +145. The HSV-1 ICP0 promoter has several potential INSM1-binding sites (red, INSM1-binding consensus site, 5′-TCCCCGGGGACG-3′; gray, INSM1-like binding site, 5′-TNNNNGGGGNCN-3′). The binding sites of well-known transcription factors are as follows: blue, Oct-1/VP16 binding site, 5′-ATGCTAATGATAT-3′. (B) HEp-2 cells were transfected with plasmid DNAs containing reporter and effector genes. Luciferase activity was measured as described in Methods. The results are shown as means ± SD, *P < 0.05 (Student's t test) relative to the empty vector (EF).