Figure 3

P-Ser⁸³-HP1γ colocalizes with Aurora A at the mitotic spindle. Representative images are shown for localization in mitotic HeLa cells. (A,B,C) Colocalization of P-Ser⁸³-HP1γ (A, green) is shown with Aurora A (B, red) at the spindle poles. The overlay is shown in (C). (D,E,F) Cells in metaphase were also stained for P-Ser⁸³-HP1γ (D, green) and Aurora B (E, red), which demonstrates that there is no colocalization of these two proteins as observed in the overlay (F). (G,H,I,J,K,L) P-Ser⁸³-HP1γ (G,J, green) was confirmed to be present at the spindle poles through co-staining with γ-tubulin (H, red) as well as α-tubulin (K, red) as shown in the overlays (I, L). (M,N,O,P,Q,R,S,T,U) In addition, CDK1 (N, red), cyclin B1 (Q, red) and cyclin B2 (T, red) were each shown to co-localize with P-Ser⁸³-HP1γ (M,P,S, green) as shown by overlays (O,R,U). Cells were counterstained with DAPI (blue) to show DNA. Scale bar represents 5 μM. CDK1, cyclin-dependent kinase 1; DAPI, 4',6-diamidino-2-phenylindole; P-Ser⁸³-HP1γ, phosphorylation of HP1γ at serine 83.