Single light-optical sections showing the distribution of HP1β (red) and centromeres (green) in 2-cell SCNT embryos at 21 hpa (a, early) and 33 hpa (b-c, late), with or without TSA treatment. The arrowhead in panel a points to a centromere associated with a NPB. Asterisks in panels b and c label chromocenters. Dashed lines delineate nuclear halves either enriched in or devoided of centromeres and chromocenters. Scale bars, 5 μm.