cAMP-dependent protein kinase (PKA) complexes probed by complementary differential scanning fluorimetry and ion mobility-mass spectrometry



Byrne, Dominic P, Vonderach, Matthias, Ferries, Samantha, Brownridge, Philip J, Eyers, Claire E ORCID: 0000-0002-3223-5926 and Eyers, Patrick A ORCID: 0000-0002-9220-2966
(2016) cAMP-dependent protein kinase (PKA) complexes probed by complementary differential scanning fluorimetry and ion mobility-mass spectrometry. BIOCHEMICAL JOURNAL, 473 (19). pp. 3159-3175.

[thumbnail of Byrne Biochemical Journal 2016 PKA IMMS.pdf] Text
Byrne Biochemical Journal 2016 PKA IMMS.pdf - Published version

Download (1MB)
[thumbnail of Byrne Biochemical Journal 2016 PKA IMMS_Supplementary.pdf] Text
Byrne Biochemical Journal 2016 PKA IMMS_Supplementary.pdf - Published version

Download (1MB)

Abstract

cAMP-dependent protein kinase (PKA) is an archetypal biological signaling module and a model for understanding the regulation of protein kinases. In the present study, we combine biochemistry with differential scanning fluorimetry (DSF) and ion mobility-mass spectrometry (IM-MS) to evaluate effects of phosphorylation and structure on the ligand binding, dynamics and stability of components of heteromeric PKA protein complexes in vitro We uncover dynamic, conformationally distinct populations of the PKA catalytic subunit with distinct structural stability and susceptibility to the physiological protein inhibitor PKI. Native MS of reconstituted PKA R2C2 holoenzymes reveals variable subunit stoichiometry and holoenzyme ablation by PKI binding. Finally, we find that although a 'kinase-dead' PKA catalytic domain cannot bind to ATP in solution, it interacts with several prominent chemical kinase inhibitors. These data demonstrate the combined power of IM-MS and DSF to probe PKA dynamics and regulation, techniques that can be employed to evaluate other protein-ligand complexes, with broad implications for cellular signaling.

Item Type: Article
Uncontrolled Keywords: Cyclic AMP-Dependent Protein Kinases, Molecular Probes, Fluorometry, Spectrometry, Mass, Electrospray Ionization, Phosphorylation
Depositing User: Symplectic Admin
Date Deposited: 03 Oct 2016 08:11
Last Modified: 19 Jan 2023 07:29
DOI: 10.1042/BCJ20160648
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3003574