Uncoupling Catalytic and Binding Functions in the Cyclic AMP-Dependent Protein Kinase A

Jonggul Kim; Geoffrey Li; Michael A Walters; Susan S Taylor; Gianluigi Veglia

doi:10.1016/j.str.2015.11.016

Uncoupling Catalytic and Binding Functions in the Cyclic AMP-Dependent Protein Kinase A

Structure. 2016 Mar 1;24(3):353-63. doi: 10.1016/j.str.2015.11.016. Epub 2016 Jan 28.

Authors

Jonggul Kim¹, Geoffrey Li², Michael A Walters³, Susan S Taylor⁴, Gianluigi Veglia⁵

Affiliations

¹ Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA; Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
² Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA.
³ Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, MN 55455, USA.
⁴ Department of Chemistry and Biochemistry, University of California at San Diego, La Jolla, CA 92093, USA.
⁵ Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA; Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA. Electronic address: vegli001@umn.edu.

Abstract

The canonical function of kinases is to transfer a phosphoryl group to substrates, initiating a signaling cascade; while their non-canonical role is to bind other kinases or substrates, acting as scaffolds, competitors, and signal integrators. Here, we show how to uncouple kinases' dual function by tuning the binding cooperativity between nucleotide (or inhibitors) and substrate allosterically. We demonstrate this new concept for the C subunit of protein kinase A (PKA-C). Using thermocalorimetry and nuclear magnetic resonance, we found a linear correlation between the degree of cooperativity and the population of the closed state of PKA-C. The non-hydrolyzable ATP analog (ATPγC) does not follow this correlation, suggesting that changing the chemical groups around the phosphoester bond can uncouple kinases' dual function. Remarkably, this uncoupling was also found for two ATP-competitive inhibitors, H89 and balanol. Since the mechanism for allosteric cooperativity is not conserved in different kinases, these results may suggest new approaches for designing selective kinase inhibitors.

Keywords: canonical and non-canonical function; cooperativity; phospholamban; protein kinase A; pseudo-kinases.

Publication types

Research Support, N.I.H., Extramural

MeSH terms

Adenosine Triphosphate / metabolism*
Animals
Azepines / pharmacology
Calorimetry
Catalytic Domain
Cyclic AMP-Dependent Protein Kinase Catalytic Subunits / chemistry*
Cyclic AMP-Dependent Protein Kinase Catalytic Subunits / metabolism*
Humans
Hydroxybenzoates / pharmacology
Isoquinolines / pharmacology
Magnetic Resonance Imaging
Models, Molecular
Nucleotides / metabolism*
Protein Binding
Protein Conformation
Sulfonamides / pharmacology

Substances

Azepines
Hydroxybenzoates
Isoquinolines
Nucleotides
Sulfonamides
ophiocordin
Adenosine Triphosphate
Cyclic AMP-Dependent Protein Kinase Catalytic Subunits
N-(2-(4-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide

Abstract

Publication types

MeSH terms

Substances

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