Editing Cyclin-dependent kinase complex (section)

=== Hinge Region ===
The conserved hinge region of CDK within eukaryotic cells acts as an essential bridge between the Gly-rich loop and the activation loop. CDK are characterized by a N-terminal lobe that is primarily twisted beta-sheet connected via this hinge region to an alpha helix dominated C-terminal lobe. In discussion of the T-loop and the Gly-rich loop, it is important to note that these regions, which must be able to spatially interact in order to carry out their biochemical functions, lie on opposite lobes of the CDK itself. Thus, this hinge region, which can vary in length slightly between CDK type and CDK-cyclin complex, connects essential regulatory regions of the CDK by connecting these lobes, and plays key roles in the resulting structure of CDK-cyclin complexes by properly orienting ATP for easy catalysis of phosphorylation reactions by the assembled complex. <ref name=":0" /><ref name=":1" />