Primary Citation of Related Structures:   1JOW
PubMed Abstract: 
Cyclin from herpesvirus saimiri (Vcyclin) preferentially forms complexes with cyclin-dependent kinase 6 (CDK6) from primate host cells. These complexes show higher kinase activity than host cell CDKs in complex with cellular cyclins and are resistant to ...
Cyclin from herpesvirus saimiri (Vcyclin) preferentially forms complexes with cyclin-dependent kinase 6 (CDK6) from primate host cells. These complexes show higher kinase activity than host cell CDKs in complex with cellular cyclins and are resistant to cyclin-dependent inhibitory proteins (CDKIs). The crystal structure of human CDK6--Vcyclin in an active state was determined to 3.1 A resolution to better understand the structural basis of CDK6 activation by viral cyclins. The unphosphorylated CDK6 in complex with Vcyclin has many features characteristic of cyclinA-activated, phosphorylated CDK2. There are, however, differences in the conformation at the tip of the T-loop and its interactions with Vcyclin. Residues in the N-terminal extension of Vcyclin wrap around the tip of the CDK6 T-loop and form a short beta-sheet with the T-loop backbone. These interactions lead to a 20% larger buried surface in the CDK6--Vcyclin interface than in the CDK2--cyclinA complex and are probably largely responsible for the specificity of Vcyclin for CDK6 and resistance of the complex to inhibition by INK-type CDKIs.
Related Citations: 
Crystallization of a Complex between Human CDK6 and a Virus-encoded Cyclin is Critically Dependent on the Addition of Small Charged Organic Molecules Schulze-Gahmen, U., Kim, S.H. () To be published --: --
Organizational Affiliation: 
Physical Bioscience Division at E. O. Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.