Fig. 5: Mapping the domains of Ki-67 interacting with pre-rRNAs.

a A schematic diagram of each domain of Ki-67. Recombinant proteins of each domain were examined by Coomassie brilliant blue (CBB). b Ki-67 associates with rRNA. Upper panel shows the workflow of protein pulling down assays. Recombinant proteins were incubated with total RNA. The RNA pull-down assays were performed followed by RT-qPCR analyses. The location of primers is shown in Supplementary Fig. S1e. c Ki-67 plays an important role in chromosome dispersion. Upper panel shows a schematic diagram of internal deletion mutants of Ki-67. Lower left panel shows the chromosome dispersion in the Ki-67-deficient cells reconstituted with full-length and mutant Ki-67. RNA FISH was detected by Cy3-labeled probe against ITS1 region, HA-tagged full-length, and truncations of Ki-67 were detected by anti-HA antibody. Lower right panel is the line analysis of the pre-rRNA, Ki-67, and DAPI signal intensity at the indicated section. Scale bar, 5 μm. d Statistic analysis of the relative fluorescence intensity of ITS1 probe along the chromosome. The results were normalized by Ki-67 expression (the signal intensity of HA tag). ***P < 0.001.