Anti-ZAK antibodies enable researchers to detect and measure the ZAK antigen in biological samples. This target is a reported synonym of the MAP3K20 gene, which encodes mitogen-activated protein kinase kinase kinase 20. This protein is known to function in cell differentiation and cytoskeleton organization, among other biological roles. The human version of ZAK has a canonical amino acid length of 800 residues and a protein mass of 91.2 kilodaltons, although 3 isoforms have been identified. It is reported to be localized in the nucleus and cytoplasm of cells and widely expressed in many tissue types. ZAK is a member of the STE Ser/Thr protein kinase protein family.