Figure 6.

Co-localization of the episome with early replication foci. The qualitative co-localization of the episome and replication foci was analyzed using pEPI FISH and BrdU pulse labeling. Maximum intensity projections were rendered from a set of serial sections. The nuclear contour was outlined with a white line. (A) Replication foci were labeled during early S-phase by incorporation of BrdU (1 h) into newly synthesized DNA. Subsequently nuclei were fixed and BrdU (red) was visualized by antibody staining. The episome (green) was visualized by pEPI FISH. Co-localizing voxels were highlighted in white color. (B) Alternatively nascent DNA was pulse-labeled with BrdU for 1 h during early S-phase, fixing and subsequent immunolocalization was done following cell division. The episome (green) was visualized by pEPI FISH. Co-localizing voxels were highlighted in white color.