Abstract

Protein Phosphatases Triggering the Dephosphorylation and Inactivation of Greatwall

Anna Castro and Thierry Lorca

Entry into mitosis requires the coordinated activation of protein kinases and phosphatases that regulate key cell cycle components allowing entry, progression and exit of mitosis. The limiting step is thought to be the activation of both Cdk1-Cyclin B and Greatwall kinases. The former promoting phosphorylation of mitotic substrates when cells enter into mitosis and the latter inhibiting PP2A-B55, responsible for dephosphorylation of these substrates. Here, we summarize recent data on the regulation of Greatwall activity and reversal of mitotic substrates phosphorylation required for mitotic exit.