Anti-MASK antibodies enable researchers to detect and measure the MASK antigen in biological samples. This target is a reported synonym of the STK26 gene, which encodes serine/threonine kinase 26. This protein is known to function in the apoptotic pathway and the regulation of cell migration, among other biological roles. The human version of MASK has a canonical amino acid length of 416 residues and a protein mass of 46.5 kilodaltons, although 3 isoforms have been identified. It is reported to be localized in the Golgi and cytoplasm of cells and notably expressed in many tissues, such as the gallbladder and skeletal muscle. MASK is a member of the STE Ser/Thr protein kinase protein family.