Investigation of Disease-Causing Point Variants of Vaccinia-Related Kinase 1 (VRK1)

Vaccinia-related kinase 1 (VRK1) is a serine/threonine kinase that plays a variety of roles in transcription regulation and the cell cycle. Its substrates include histones, p53, and coilin. The kinase activity of the VRK1 protein is largely controlled by its C-terminal tail, which interacts with the enzyme active site. Several rare point mutations in VRK1 (including L195V, R89Q, and Y213H) are associated with neurodegenerative disorders, and questions remain as to how these mutations affect VRK1's intrinsic stability and activity. For this in vitro study, mutations were generated in a His-tagged VRK1 kinase domain construct, and proteins were expressed in E. coliand purified. The mutant proteins' folding and stability were analyzed by circular dichroism, and ligand binding was investigated using differential scanning fluorimetry. Protein modeling in PyMOL was also used to visualize the kinase and its associated changes. © FASEB.