The phosphatases CDC14A and CDC14B bind directly to MAPK6 as assessed by yeast two hybrid and by co-immunoprecipitation (Tanguay et al, 2010; Hansen et al, 2008). CDC14 phosphatases are able to reverse the CDK1-dependent phosphorylation of MAPK6 in vitro, and overexpression of WT but not catalytically inactive forms of CDC14A or B in vivo leads to dephosphorylation of T698 (Hansen et al, 2008; Tanguay et al, 2010). These results suggest that CDC14 phosphatases reverse the CDK1-dependent phosphorylation of MAPK6 during mitosis. These reactions are depicted as occuring in the nucleoplasm, but the site of action has not been determined, and CDC14 and MAPK6 colocalize throughout the cell (Hansen et al, 2008).