Phased by Notch

On page 157, Sarmento and colleagues show how the developmental regulator protein Notch1 advances the cell cycle. Activation of Notch1 induced the production of a protein that chops up cell cycle inhibitors, leading to a shortened G1 phase and a faster transition into S phase (but no overall increase in proliferation).

The Notch family of transmembrane receptors regulates both cell fate decisions and the maintenance of adult stem cells, processes that require precise control of the cell cycle. Although Notch1 activation had previously been shown to alter the cell cycle in hematopoietic progenitor cells and to delay their commitment to the myeloid lineage, a direct link between Notch1 and cell cycle control...