Probable protein tyrosine phosphatase. Has phosphatase activity with synthetic substrates (PubMed:15252030, PubMed:29106959). Has a phosphatase activity-independent regulatory role in MAP3K5/ASK1-mediated apoptosis, preventing MAP3K5/ASK1 inhibition by AKT1. Shows no phosphatase activity on MAPK1/ERK2, MAPK8/JNK, MAPK14/p38 and MAP3K5/ASK1. H2O + O-phospho-L-tyrosyl-[protein] = L-tyrosyl-[protein] + phosphate H2O + O-phospho-L-seryl-[protein] = L-seryl-[protein] + phosphate H2O + O-phospho-L-threonyl-[protein] = L-threonyl-[protein] + phosphate Inhibited by vanadate. Monomer (PubMed:29106959). Interacts with MAP3K5/ASK1; may compete with AKT1 preventing MAP3K5/ASK1 phosphorylation by AKT1. Additional isoforms seem to exist. Skeletal muscle specific. Produced by alternative promoter usage. Produced by alternative promoter usage and alternative splicing. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. Produced by alternative promoter usage and alternative splicing. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. Produced by alternative promoter usage and alternative splicing. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. Produced by alternative promoter usage and alternative splicing. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. Belongs to the protein-tyrosine phosphatase family. Non-receptor class dual specificity subfamily. Wrong choice of CDS. Wrong choice of CDS. Wrong choice of CDS. Wrong choice of CDS. Wrong choice of CDS. Truncated C-terminus. Wrong choice of CDS.