Fig. 1.

Depletion of MLL5 by RNA interference causes genomic instability. (A) The average percentage of multinuclear cells in Negative Control-siRNA (NC-siRNA) and MLL5-siRNA-treated U2OS cells (P = 0.001, paired Student's t-test). Tubulin was stained green and nuclei were stained red. Arrowheads denotes multinuclear cells. Scale bars: 20 µm. (B) The cells were transfected with NC-siRNA, MLL5-siRNA or MLL5-siRNA-N every other day and harvested at day 7 for FISH. The percentage of cells exhibiting abnormal numbers of chromosomes 8 and 10 was scored (n>100 cells per sample). Scale bars: 5 µm. (C) The mitotic progression of U2OS cells expressing H2B-mCherry was monitored by live-cell imaging. Scale bars: 10 µm. (D) Cell cycle analyses showed that MLL5-depleted cells remained at 4N DNA content after releasing from nocodazole, and polyploid populations gradually increased. Noc, nocodazole.