Fig. 6

Potential problems. a1. Misaligned B23 (green), H3K4me3 (red) and DAPI (grey) channel. a2 shows an enlargement of the box in a1. Arrows mark the gap between the signals that should be aligned. b. H3K4me3 staining at the periphery occasionally caused by using the blocking buffer developed by Markaki et al. [21] and utilized by Huebner et al. [22] without such an effect. c1. Movement during scanning may have caused short lines instead of round nuclear pores as visualized by a NUP153 staining. c2. The DAPI channel from the same nucleus as shown in c2 is blurry. c3. The lines of lamin B of the same nucleus as shown in c1 and c2 are duplicated. d1. Blurry X/Y section of a DAPI stained nucleus next to another DAPI stained nucleus at the right top border. d2. The X/Z section marked in D1 shows lines emanating from all four corners caused by the second nucleus (marked by arrows; compare with Figure 4 D1). d3. These lines interfere with the signals produced by the central nucleus. e. Rabbit anti CDX2 staining of a rabbit blastocyst recorded by confocal microscopy shows a normal staining pattern outside the zona pellucida, a strongly stained zona pellucida and an altered staining pattern of blastomeres inside the zona pellucida when compared with nuclei outside the zona pellucida