VRK3 is a member of the protein kinase superfamily. The VRK3 gene has replacements at a number of residues within the ATP binding motifs which in other kinases were proved to be required for catalysis in both human and mouse. In vitro assays show that VRK3 has no phosphorylation activity but probably holds its substrate binding capability. VRK3 is universally expressed in human tissues and its protein is restricts to the nucleus.
