DUSP13 is a dual specificity phosphatase (DSP), dephosphorylating tyrosine and serine/threonine residues, and is expressed in two forms. DUSP13B, or testis and skeletal muscle-specific dual specificity phosphatase (TMDP), has been shown inhibit MAPK activation and AP-1-dependent gene expression. DUSP13A, or muscle-restricted dual specificity phosphatase (MDSP), does not display either of these functions.
