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In Search of Small Molecule Inhibitors Targeting the Flexible CK2 Subunit Interface.

ABSTRACT: Protein kinase CK2 is a tetrameric holoenzyme composed of two catalytic (? and/or ?') subunits and two regulatory (?) subunits. Crystallographic data paired with fluorescence imaging techniques have suggested that the formation of the CK2 holoenzyme complex within cells is a dynamic process. Although the monomeric CK2? subunit is endowed with a constitutive catalytic activity, many of the plethora of CK2 substrates are exclusively phosphorylated by the CK2 holoenzyme. This means that the spatial and high affinity interaction between CK2? and CK2? subunits is critically important and that its disruption may provide a powerful and selective way to block the phosphorylation of substrates requiring the presence of CK2?. In search of compounds inhibiting this critical protein-protein interaction, we previously designed an active cyclic peptide (Pc) derived from the CK2? carboxy-terminal domain that can efficiently antagonize the CK2 subunit interaction. To understand the functional significance of this interaction, we generated cell-permeable versions of Pc, exploring its molecular mechanisms of action and the perturbations of the signaling pathways that it induces in intact cells. The identification of small molecules inhibitors of this critical interaction may represent the first-choice approach to manipulate CK2 in an unconventional way.

SUBMITTER: Bestgen B

PROVIDER: S-EPMC5374420 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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In Search of Small Molecule Inhibitors Targeting the Flexible CK2 Subunit Interface.

Bestgen Benoît B Belaid-Choucair Zakia Z Lomberget Thierry T Le Borgne Marc M Filhol Odile O Cochet Claude C

Pharmaceuticals (Basel, Switzerland) 20170203 1

Protein kinase CK2 is a tetrameric holoenzyme composed of two catalytic (α and/or α') subunits and two regulatory (β) subunits. Crystallographic data paired with fluorescence imaging techniques have suggested that the formation of the CK2 holoenzyme complex within cells is a dynamic process. Although the monomeric CK2α subunit is endowed with a constitutive catalytic activity, many of the plethora of CK2 substrates are exclusively phosphorylated by the CK2 holoenzyme. This means that the spatial ...[more]

PMID: 28165359

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Dataset Information

In Search of Small Molecule Inhibitors Targeting the Flexible CK2 Subunit Interface.

Publications

In Search of Small Molecule Inhibitors Targeting the Flexible CK2 Subunit Interface.

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