PPM1G (Protein phosphatase 1G) is a member of the PP2C family of Serine/threonine protein phosphatases. PP2C family members are known to be negative regulators of cell stress response pathways. The human Ser/Thr phosphatase PPM1G promotes spliceosome assembly. This phosphatase is found to be responsible for the dephosphorylation of Pre-mRNA splicing factors, which is important for the formation of functional spliceosome.