The study of the determinants controlling Arpp19 phosphatase-inhibitory activity reveals an Arpp19/PP2A-B55 feedback loop

Abstract

Progression of the cell division cycle requires feedback loops including those of phosphorylation and dephosphorylation; however the precise regulation of phosphorylation kinetics of Arpp19, an inhibitor of protein phosphatase 2A, is unclear. Here, the authors report that feedback between phosphorylation states of Ser67 and Ser109 of Arpp19 coordinates Arpp19-dependent inhibition of PP2A-B55 and Cyclin B activation during cell cycle progression.