Cell size control: governed by a spatial gradient.
The phenomenon of cell size homeostasis, whereby cells coordinate growth and division to maintain a uniform cell size, has been an outstanding issue in cell biology for many decades. Two recent studies in Nature in fission yeast demonstrate that a gradient of the polarity factor Pom1 is a sensor of cell length that determines the onset of Cdc2 activation and mitosis.
Almeida R, Tyers M