Evolved to Be Active: Sulfate Ions Define Substrate Recognition Sites of CK2alpha and Emphasise its Exceptional Role within the CMGC Family of Eukaryotic Protein KinasesNiefind, K., Yde, C.W., Ermakova, I., Issinger, O.G.
(2007) J Mol Biol 370: 427-438
- PubMed: 17524418
- DOI: 10.1016/j.jmb.2007.04.068
- Structures With Same Primary Citation
- PubMed Abstract:
- Crystal structure of a C-terminal deletion mutant of human protein kinase CK2 catalytic subunit
Ermakova, I., Boldyreff, B., Issinger, O.-G., Niefind, K.
(2003) J Mol Biol 330: 925
- Crystal structure of human protein kinase CK2: insights into basic properties of the CK2 holoenzyme
Niefind, K., Guerra, B., Ermakova, I., Issinger, O.-G.
(2001) EMBO J 20: 5320
- Inclining the purine base binding plane in protein kinase CK2 by exchanging the flanking side-chains generates a preference for ATP as a cosubstrate.
Yde, C.W., Ermakova, I., Issinger, O.-G., Niefind, K.
(2005) J Mol Biol 347: 399
CK2alpha is the catalytic subunit of protein kinase CK2 and a member of the CMGC family of eukaryotic protein kinases like the cyclin-dependent kinases, the MAP kinases and glycogen-synthase kinase 3. We present here a 1.6 A resolution crystal struct ...
CK2alpha is the catalytic subunit of protein kinase CK2 and a member of the CMGC family of eukaryotic protein kinases like the cyclin-dependent kinases, the MAP kinases and glycogen-synthase kinase 3. We present here a 1.6 A resolution crystal structure of a fully active C-terminal deletion mutant of human CK2alpha liganded by two sulfate ions, and we compare this structure systematically with representative structures of related CMGC kinases. The two sulfate anions occupy binding pockets at the activation segment and provide the structural basis of the acidic consensus sequence S/T-D/E-X-D/E that governs substrate recognition by CK2. The anion binding sites are conserved among those CMGC kinases. In most cases they are neutralized by phosphorylation of a neighbouring threonine or tyrosine side-chain, which triggers conformational changes for regulatory purposes. CK2alpha, however, lacks both phosphorylation sites at the activation segment and structural plasticity. Here the anion binding sites are functionally changed from regulation to substrate recognition. These findings underline the exceptional role of CK2alpha as a constitutively active enzyme within a family of strictly controlled protein kinases.
Universität zu Köln, Institut für Biochemie, Zülpicher Strasse 47, D-50674 Köln, Germany. Karsten.Niefind@uni-koeln.de