Blooming too soon: timing is crucial to error-free cell division

The Bloom (BLM) DNA helicase is an important enzyme in DNA repair and the maintenance of genome stability. Mutations in BLM are associated with Bloom’s Syndrome, a disease characterized by growth defects and increased susceptibility to cancer. In their latest study, published in Science Advances, the lab of Joao Matos and their colleagues at the IRB-Bellinzona and ETH-Zürich (Switzerland) have elucidated the mechanism that regulates the correct timing of BLM activity during mitotic cell division. They show that BLM activity depends on its phosphorylation by two cell cycle kinases and that active BLM promotes the dissolution of potentially dangerous recombination intermediates.