Related Experiment Video
Updated: May 21, 2026
12:26
Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay
Published on: May 3, 2018
A phosphorylation hotspot within the occludin C-terminal domain
1Department of Biochemistry II, Jena University Hospital, Friedrich-Schiller-University Jena, Germany.
Annals of the New York Academy of Sciences
|June 8, 2012
Summary
Occludin phosphorylation regulates tight junction assembly and function. This study highlights a key phosphorylation hotspot in occludin
Area of Science:
- Cell biology
- Molecular biology
- Biochemistry
Background:
- Tight junctions (TJs) form crucial paracellular barriers in epithelial and endothelial cells.
- Occludin, a tetraspanin protein, is vital for TJ structure and function, and its activity is modulated by phosphorylation.
Purpose of the Study:
- To summarize the role of occludin phosphorylation in TJ assembly, disassembly, and function.
- To focus on a specific phosphorylation hotspot in the C-terminal cytoplasmic domain of occludin and its impact.
Main Methods:
- Literature review and summary of existing research on occludin phosphorylation.
- Analysis of the C-terminal cytoplasmic domain of occludin, focusing on phosphorylation sites and their proximity to other functional regions.
Main Results:
- Occludin phosphorylation by kinases like c-Src, PKCs, and CK2 influences TJ protein localization, dynamics, and interactions.
- A specific 11-amino acid region (Tyr398-Ser408) acts as a phosphorylation hotspot, affecting occludin dimerization and its association with ZO-1.
Conclusions:
- Phosphorylation of the occludin hotspot significantly impacts TJ regulation.
- Further research is needed to fully elucidate the functional consequences of this phosphorylation hotspot on TJ dynamics and barrier function.
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