Chemokine CXCL8 modulates GluR1 phosphorylation.
Myriam Catalano1, Flavia Trettel, Raffaela Cipriani
1Istituto Pasteur-Fondazione Cenci Bolognetti, Centro di Eccellenza BEMM, Università di Roma "Sapienza", P.le A. Moro 5, I00185 Roma, Italy.
Journal of Neuroimmunology
|May 30, 2008
Summary
The phosphorylation of serine 845 (S845) on the GluR1 subunit is key for the interaction between GluR1 and its receptor CXCR2. This interaction is crucial for regulating cell migration induced by the chemokine interleukin 8 (CXCL8).
Area of Science:
- Neuroscience
- Cell Biology
- Molecular Biology
Background:
- Interleukin 8 (CXCL8) is a chemokine that plays a role in neuronal function.
- CXCL8 signaling involves its receptor CXCR2.
- The GluR1 subunit of AMPA-type glutamate receptors is implicated in neuronal plasticity and function.
Purpose of the Study:
- To investigate the role of GluR1 phosphorylation in the interaction with CXCR2.
- To determine the impact of this interaction on CXCL8-induced cell migration.
Main Methods:
- Site-directed mutagenesis of the GluR1 subunit (S845 to Alanine or Glutamate).
- Co-immunoprecipitation assays to assess GluR1/CXCR2 interaction.
- Functional assays to measure CXCL8-induced cell migration.
Main Results:
- Phosphorylation of serine 845 (S845) on GluR1 is essential for its physical interaction with CXCR2.
- Mutating S845 to Alanine abolished the interaction and rescued CXCL8-induced cell migration.
- Mutating S845 to Glutamate did not affect the interaction or cell migration.
Conclusions:
- The phosphorylated state of S845GluR1 is a critical determinant for the physical coupling between GluR1 and CXCR2.
- This interaction modulates CXCL8-mediated cellular responses, specifically cell migration.
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