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Updated: Jun 19, 2026
09:16
Oligopeptide Competition Assay for Phosphorylation Site Determination
Published on: May 18, 2017
The interaction between casein kinase Ialpha and 14-3-3 is phosphorylation dependent
Samuel Clokie1, Helen Falconer, Shaun Mackie
1Institute of Structural Biology, Edinburgh University, UK.
The FEBS Journal
|October 29, 2009
Summary
Casein kinase Ialpha (CKIalpha) binds to 14-3-3 proteins through phosphorylation-dependent interactions. This study identifies key binding sites and demonstrates conserved interactions across species.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Signaling
Background:
- Casein kinase Ialpha (CKIalpha) phosphorylates 14-3-3 zeta and tau proteins.
- CKIalpha's role in regulating protein interactions is crucial for cellular processes.
Purpose of the Study:
- To investigate the association between CKIalpha and 14-3-3 proteins.
- To identify the molecular mechanisms and binding sites governing this interaction.
- To explore the conservation of this interaction in different organisms.
Main Methods:
- In vitro and in vivo association assays.
- Site-directed mutagenesis of CKIalpha.
- Peptide competition assays.
- Analysis of homologous kinases and 14-3-3 proteins in yeast.
Main Results:
- CKIalpha associates with 14-3-3 proteins in a phosphorylation-dependent manner.
- A specific binding site involving Ser242 in CKIalpha was identified as a principal interaction site.
- The interaction is specific for certain 14-3-3 isoforms and can be blocked by competitive peptides.
- Homologous kinases in yeast phosphorylate yeast 14-3-3 proteins at equivalent sites.
Conclusions:
- CKIalpha and 14-3-3 proteins interact via phosphorylation-dependent mechanisms.
- The identified binding sites and conserved interactions highlight the importance of this pathway in cellular regulation.
- This interaction is conserved across mammalian and yeast systems, suggesting a fundamental biological role.
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