Catalytically inactive phosphatase. Acts as a nuclear anchor for MAPK1/MAPK3 (ERK1/ERK2). Modulates cell-fate decisions and cell migration by spatiotemporal regulation of MAPK1/MAPK3 (ERK1/ERK2). By binding to the F-box of FBXW7, prevents the assembly of FBXW7 into the SCF E3 ubiquitin-protein ligase complex, and thereby inhibits degradation of its substrates (By similarity). Plays a role in spermatogenesis (By similarity).
Subcellular locations: Nucleus, Cytoplasm, Cytosol
Predominantly localizes to the nucleus.