Figure 5. The CHPKs show minor effects on the numbers of PML-NBs per cell.

(A) U-2 OS cells plated on coverslips were transfected with the indicated CHPK (1–8) or HCMV IE1 and 24 hours later were harvested and stained for indirect immunofluorescence with antibodies for PML, the HA epitope, and Hoechst (not pictured). Representative images showing PML (green) and the CHPK or IE1 (red) are displayed. Arrows denote CHPK/IE1 expressing cells. Images are grouped into the alpha-herpesvirus proteins (top), beta-herpesvirus proteins (middle), and gamma-herpesvirus proteins plus the IE1 control (bottom) (B) Using the same coverslips as in A, the number of PML-NB domains was counted in at least 100 kinase positive nuclei for three independent experiments. The frequency with which any specific number of PML-NBs was observed in an individual cell was plotted with Microsoft Excel as a best-fit curve. Control (dashed line) and IE1 expressing cells (black line) are shown in each graph for comparison. The average number of PML-NBs per cell was also determined from this data (see Table 3) and statistically significant differences from control cells are denoted with an asterisk (* indicates P≤0.05). Herpesvirus families are grouped as above.