Crystallization of gankyrin, an oncoprotein that interacts with CDK4 and the S6b (rpt3) ATPase of the 19S regulator of the 26S proteasome.

Gankyrin is an oncoprotein overexpressed in hepatocarcinoma cells that binds to the cell-cycle regulator CDK4 and the S6b ATPase subunit of the regulatory component of the proteasome. It belongs to the family of ankyrin-repeat proteins that appear to mediate protein-protein interactions in diverse biochemical processes. Gankyrin has been crystallized from polyethylene glycol solutions and diffraction data have been obtained from these crystals that extend to 2.1 A spacing.