Journal Article

lncreased risk of slippage upon disengagement of the mitotic checkpoint

Bonaiuti, Paolo, Ciliberto, Andrea, Stier, Alma Beatrix, Juhász, János, Gross, Fridolin

2025

Overview

Drugs that impair microtubule dynamics alter microtubule-kinetochore attachment and invoke the mitotic checkpoint which arrests cells in mitosis. The arrest can last for hours, but it is leaky: cells adapt (i.e., slip out of it) and exit from mitosis. Here, we investigate the mechanism that allows cells to escape, and whether it is possible to prevent it. Based on a model of the mitotic checkpoint which includes the presence of a positive feedback loop, the escape from the arrest is described as a stochastic transition driven by fluctuations of molecular components from a checkpoint ON to a checkpoint OFF state. According to the model, drug removal further facilitates adaptation, a prediction we confirmed in budding yeast. The model suggests two ways to avoid adaptation: inhibition of APC/C and strengthening the mitotic checkpoint. We confirmed experimentally that both alterations decrease the chance of cells slipping out of mitosis, during a prolonged arrest and after washing out the drug. Our results may be relevant for increasing the efficiency of microtubule depolymerizing drugs.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Adaptation / Biology and Life Sciences / Cell cycle / Cell division / Chromosomes / Computational Biology / Depolymerization / Drug interactions / Drugs / Feedback loops / M Phase Cell Cycle Checkpoints - drug effects / M Phase Cell Cycle Checkpoints - physiology / Medical research / Microtubules / Microtubules - drug effects / Microtubules - metabolism / Microtubules - physiology / Mitosis / Mitosis - drug effects / Mitosis - physiology / Models, Biological / Pharmacology, Experimental / Physiological aspects / Positive feedback / Research and Analysis Methods / Saccharomyces cerevisiae / Simulation / Slippage / Yeast