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Updated: Jan 8, 2026
10:05
Studying RNA Interactors of Protein Kinase RNA-Activated during the Mammalian Cell Cycle
Published on: March 5, 2019
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Protein kinase a regulates cyclooxygenase-2 expression through the RNA-binding proteins HuR and TTP
Sendi Rafael Adame-Garcia1, Thomas S Hoang1, Pham Thuy Thien Vo1
1Moores Cancer Center, University of California San Diego, La Jolla, California, USA; Department of Pharmacology, School of Medicine, University of California San Diego, La Jolla, California, USA.
The Journal of Biological Chemistry
|December 20, 2025
Summary
Protein kinase A (PKA) enhances cyclooxygenase-2 (COX-2) expression in macrophages. PKA increases COX-2 mRNA stability by modulating RNA-binding proteins HuR and TTP.
Area of Science:
- Molecular Biology
- Immunology
- Cell Biology
Background:
- Cyclooxygenase-2 (COX-2) is crucial for inflammatory responses.
- Elevated intracellular cAMP stimulates COX-2 expression, but the mechanism is unclear.
- Protein kinase A (PKA) is the primary cAMP effector.
Purpose of the Study:
- Investigate the role of PKA in regulating COX-2 expression in macrophages.
- Elucidate the post-transcriptional mechanisms involved.
Main Methods:
- Assessed PKA activity in macrophages.
- Studied interactions between PKA, HuR, TTP, and COX-2 mRNA.
- Utilized pharmacological inhibitors and mRNA-binding assays.
Main Results:
- PKA activity is essential for COX-2 expression via post-transcriptional regulation.
- PKA enhances COX-2 mRNA stability by interacting with HuR and TTP.
- PKA activation increases HuR binding and decreases TTP binding to COX-2 mRNA.
Conclusions:
- PKA enhances COX-2 expression by stabilizing its mRNA through HuR and TTP.
- RNA-binding proteins are novel effectors of PKA signaling in post-transcriptional regulation.
- Findings reveal a mechanistic link between PKA and COX-2 mRNA stability.
Keywords:
RNA binding proteinsciclooxigenase-2postranscriptional regulationprotein kinase Asignal transductionMore Related Videos
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