In vitro PKA phosphorylation-mediated human PDE4A4 activation
| Autor: | France Laliberté, Susana Liu, Elise Gorseth, Brian Bobechko, Adrienne Bartlett, Paula Lario, Michael J Gresser, Zheng Huang |
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| Jazyk: | angličtina |
| Předmět: |
Cations
Divalent Protein subunit Biophysics Sf9 Mg2+ Biochemistry Divalent Hydrolysis Structural Biology Cyclic AMP Genetics Humans Magnesium PKA Phosphorylation Molecular Biology chemistry.chemical_classification Cofactor binding Cell Biology Cyclic AMP-Dependent Protein Kinases In vitro Cyclic Nucleotide Phosphodiesterases Type 4 Enzyme Activation Enzyme chemistry 3' 5'-Cyclic-AMP Phosphodiesterases PDE4 Rolipram |
| Zdroj: | FEBS Letters. (1-3):205-208 |
| ISSN: | 0014-5793 |
| DOI: | 10.1016/S0014-5793(02)02259-7 |
| Popis: | The PDE4 catalytic machinery comprises, in part, two divalent cations in a binuclear motif. Here we report that PDE4A4 expressed in Sf9 cells exhibits a biphasic Mg2+ dose–response (EC50 of ∼0.15 and >10 mM) in catalyzing cAMP hydrolysis. In vitro phosphorylation of PDE4A4 by the PKA-catalytic subunit increases the enzyme’s sensitivity to Mg2+, leading to 4-fold increased cAMP hydrolysis without affecting its Km. The phosphorylation also increases the potencies of (R)- and (S)-rolipram without affecting CDP-840 and SB-207499. The results support that modulating the cofactor binding affinity of PDE4 represents a mechanism for regulating its activity. |
| Databáze: | OpenAIRE |
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