Figure 8.

A model: how cohesin and topo II are implicated in metaphase chromosome alignment. A model illustrating how cohesin and topo II contribute to chromosome alignment in metaphase. (A) Metaphase and anaphase chromosomes of non-RNAi HeLa cells. (B) Preseparated chromosomes in hRad21RNAi. (C) hRad21 Topo II RNAi cells. (D) Topo II RNAi cells. (E) hRad21 RNAi cells treated with ICRF-193. Chromosome, blue; the link regulated by cohesin and topo II, green; spindle, orange. The eye represents surveillance by Mad2-dependent spindle checkpoint control. Kinetochores colored in pink indicate activation of spindle checkpoint, whereas the inactivated checkpoint is indicated by yellow kinetochores. Spindle checkpoint is activated in all the cases except for control non-RNAi cells.