InterPro: IPR020417 Dual specificity phosphatase

Dual Specificity Phosphatases (DUSPs) are members of the superfamily of Protein Tyrosine Phosphatases (PTPs). They remove the phosphate group from both phospho-tyrosine and phospho-serine/threonine residues. Many of these proteins have been related to the MAP kinase signalling pathway and hence they are also termed MAP kinase phosphatases (MKPs). A group of DUSPs share a high degree of similarity with the MKP subgroup, but lack the N-terminal regulatory domain, which provides the substrate specificity towards the MAP kinases. These proteins form a heterogeneous group and have in common the presence of a single catalytic PTP domain. They are small-sized and have been named Low Molecular Weight-DUSPs (LMW-DUSPs) or Atypical-DUSPs. VHR was the first characterised member of this subfamily; its crystal structure is known [1, 2].

The functions of many of the members of this group remain unknown, although some have been related to regulation of MAP kinase pathways [3, 4, 5]. VHR has also been related to the control of cell-senescence [6]. On the basis of sequence similarity, this family can be subdivided into two groups, for convenience termed A and B.