Dual specificity protein phosphatases inactivate their target kinases by dephosphorylating both the;phosphoserine/threonine and phosphotyrosine residues. They negatively regulate members of the MAPK superfamily;(MAPK/ERK, SAPK/JNK, p38), which is associated with cellular proliferation and differentiation. Different members of;this family of dual specificity phosphatases show distinct substrate specificities for MAPKs, different tissue;distribution and subcellular localization, and different modes of inducibility of their expression by extracellular;stimuli. This gene product binds to and inactivates p38 and SAPK/JNK, but not MAPK/ERK. Its subcellular localization;is unique; it is evenly distributed in both the cytoplasm and the nucleus. This gene is widely expressed in various;tissues and organs, and its expression is elevated by stress stimuli. Three transcript variants encoding two different;isoforms have been found for this gene.