Primary Citation of Related Structures:   4IB5
PubMed Abstract: 
The constitutively active Ser/Thr kinase CK2 (casein kinase 2) is used by tumor cells to acquire apoptosis resistance. CK2 exists as a heterotetrameric holoenzyme with two catalytic chains (CK2α) attached to a dimer of noncatalytic subunits (CK2β). A druggable cavity at the CK2β interface of CK2α allows the design of small molecules disturbing the CK2α/CK2β interaction and thus affecting activity, stability, and substrate specificity ...
The constitutively active Ser/Thr kinase CK2 (casein kinase 2) is used by tumor cells to acquire apoptosis resistance. CK2 exists as a heterotetrameric holoenzyme with two catalytic chains (CK2α) attached to a dimer of noncatalytic subunits (CK2β). A druggable cavity at the CK2β interface of CK2α allows the design of small molecules disturbing the CK2α/CK2β interaction and thus affecting activity, stability, and substrate specificity. We describe here the first structure of CK2α with an effective CK2β-competitive compound, namely, a 13-meric cyclic peptide derived from the C-terminal CK2β segment. Some well-ordered water molecules not visible in CK2 holoenzyme structures were detected at the interface. Driven mainly by enthalpy, the peptide binds with submicromolar affinity to CK2α, stimulates its catalytic activity, and reduces effectively the CK2α/CK2β affinity. The results provide a thermodynamic and structural rationalization of the peptide's CK2β-competitive functionality and pave thus the way to a peptidomimetic drug addressing the CK2α/CK2β interaction.
Related Citations: 
Crystal structure of human protein kinase CK2: insights into basic properties of the CK2 holoenzyme Niefind, K., Guerra, B., Ermakowa, I., Issinger, O.G. (2001) EMBO J 20: 5320
Structure-based design of small peptide inhibitors of protein kinase CK2 subunit interaction. Laudet, B., Barette, C., Dulery, V., Renaudet, O., Dumy, P., Metz, A., Prudent, R., Deshiere, A., Dideberg, O., Filhol, O., Cochet, C. (2007) Biochem J 408: 363
Organizational Affiliation: 
School of Chemistry, University of Leicester University Road Leicester LE1 7RH UK.