Nature, Published online: 28 October 2026; doi:10.1038/d41586-026-03288-5

A previously unknown mechanism required for cells to start proliferating has been identified. A combination of mathematical modelling and cell-based experiments shows that the enzyme WEE1 switches off a protein-degradation complex to allow cell proliferation to start, with implications for WEE1 inhibitors currently in trials for cancer treatments.