# Safeguarding genome integrity: Polo-like kinase Cdc5 and phosphatase Cdc14 orchestrate Topoisomerase II-mediated catenane resolution in mitosis

## TL;DR

This study reveals how two enzymes, Cdc5 and Cdc14, work together to untangle DNA during cell division, ensuring accurate chromosome separation and genome stability.

## Contribution

The study identifies a novel coordination mechanism between Cdc5 and Cdc14 in regulating Topoisomerase II to resolve DNA intertwines during mitosis.

## Key findings

- Cdc14 and Cdc5 regulate Topoisomerase II through SUMOylation and phosphorylation to resolve DNA catenanes.
- The collaboration between Cdc5 and Cdc14 ensures timely removal of sister chromatid linkages during mitosis.
- This mechanism preserves chromosome segregation and genome integrity during cell division.

## Abstract

Resolution of sister chromatid intertwines in mitosis is vital for safeguarding genome integrity. While cohesin, condensin, the polo-like kinase Cdc5, and the phosphatase Cdc14 have all been implicated in this process, the underlying molecular mechanisms remain elusive. Our study unveils a coordination between spindle elongation and the timely resolution of DNA linkages, orchestrated by Cdc14 and Cdc5. We show that Cdc14 and Cdc5 collaborate to facilitate the resolution of DNA catenanes, the predominant species of DNA intertwines in mitosis, by regulating Topoisomerase II (Top2) function, both through SUMOylation and phosphorylation. Our findings contribute to unraveling a mechanism wherein Cdc5 and Cdc14 work together to ensure the timely removal of all sources of linkages between sister chromatids, thereby preserving the integrity of chromosome segregation and genome stability.

Graphical Abstract