Sandbox Reserved 826: Difference between revisions

In order to gain structural information about CDKs, a crystallographic analysis of CDK in complex with cyclin D was performed. CDK4 and cyclin D1, were overexpressed in insect cells for crystallisation and slightly modified for better crystallization. CDK 4 possesses the typical bilobal structure of kinases, containing a 5-strandet ß-sheet and a N-terminal domain (residues 1-96). Within the N-terminal domain the helix alpha-C is packed against the ß-sheet. Furthermore an ATP binding site is located in between these domains, which might bind ATP after minimal conformational rearrangement of residues Asp-99, Asp-140, Lys-142, and Tyr-17. Residues 161-171 form a T-loop containing alpha-helices. Phosphorylation of this T-loop or cyclin D binding may change its conformation in order to activate kinase activity of CDK4. Lambda-phosphatase incubation studies confirm the importance of phosphorylation of the T-loop for full kinase activity <ref> PMID: 19237565 </ref>.