Journal
JOURNAL OF BIOLOGICAL CHEMISTRY
Volume 287, Issue 53, Pages 44192-44202Publisher
AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC
DOI: 10.1074/jbc.M112.422956
Keywords
-
Categories
Funding
- Agence Nationale de la Recherche (HyperEpac Genopath09)
- Region Midi-Pyrenees
- Association Francaise contre les Myopathies
- Fondation pour la Recherche Medicale (Programme Cardiovasculaire)
- Centre National de la Recherche Scientifique
Ask authors/readers for more resources
The cAMP-binding protein Epac is a therapeutic target for the treatment of various diseases such as cardiac hypertrophy and tumor invasion. This points out the importance to develop Epac inhibitors to better understand the involvement of these cAMP sensors in physiology and pathophysiology. Here, we have developed a functional fluorescence-based high-throughput assay with a Z' value around 0.7 for screening Epac-specific antagonists. We identified an Epac1 inhibitor compound named CE3F4 that blocked Epac1 guanine nucleotide exchange activity toward its effector Rap1 both in cell-free systems and in intact cells. CE3F4 is a tetrahydroquinoline analog that fails to influence protein kinase A holoenzyme activity. CE3F4 inhibited neither the interaction of Rap1 with Epac1 nor directly the GDP exchange on Rap1. The kinetics of inhibition by CE3F4 indicated that this compound did not compete for binding of agonists to Epac1 and suggested an uncompetitive inhibition mechanism with respect to Epac1 agonists. A structure-activity study showed that the formyl group on position 1 and the bromine atom on position 5 of the tetrahydroquinoline skeleton were important for CE3F4 to exert its inhibitory activity. Finally, CE3F4 inhibited Rap1 activation in living cultured cells, following Epac activation by either 8-(4-chlorophenylthio)-2'-O-methyl-cAMP, an Epac-selective agonist, or isoprenaline, a non-selective beta-adrenergic receptor agonist. Our study shows that CE3F4 and related compounds may serve as a basis for the development of new therapeutic drugs.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available