The role of cell growth rate on accumulation of the mitotic cyclin Cdc13 in fission yeast.

Cell growth rate does not influence the time-dependent accumulation of Cdc13 in fission yeast interphase cells.

• Why it matters: Understanding how cells regulate cyclin levels independently of growth rate helps clarify mechanisms of size control and cell cycle progression, which are crucial for maintaining cellular homeostasis.
• What they did: The study combined experiments and mathematical modeling to analyze Cdc13 stability, its dilution by growth, and the effects of nutrient conditions on its accumulation and Cdk1 activation in fission yeast.
• The result: Cdc13 accumulation remains unaffected by changes in growth rate but can be modulated by nutrient-specific mechanisms, with low glucose increasing nuclear Cdc13 concentration despite reduced cell size, and poor nitrogen decreasing both growth and Cdc13 levels.