PKA-type I selective constrained peptide disruptors of AKAP complexes

ACS Chem Biol. 2015 Jun 19;10(6):1502-10. doi: 10.1021/acschembio.5b00009. Epub 2015 Mar 25.

Abstract

A-Kinase Anchoring Proteins (AKAPs) coordinate complex signaling events by serving as spatiotemporal modulators of cAMP-dependent protein kinase activity in cells. Although AKAPs organize a plethora of diverse pathways, their cellular roles are often elusive due to the dynamic nature of these signaling complexes. AKAPs can interact with the type I or type II PKA holoenzymes by virtue of high-affinity interactions with the R-subunits. As a means to delineate AKAP-mediated PKA signaling in cells, we sought to develop isoform-selective disruptors of AKAP signaling. Here, we report the development of conformationally constrained peptides named RI-STapled Anchoring Disruptors (RI-STADs) that target the docking/dimerization domain of the type 1 regulatory subunit of PKA. These high-affinity peptides are isoform-selective for the RI isoforms, can outcompete binding by the classical AKAP disruptor Ht31, and can selectively displace RIα, but not RIIα, from binding the dual-specific AKAP149 complex. Importantly, these peptides are cell-permeable and disrupt Type I PKA-mediated phosphorylation events in the context of live cells. Hence, RI-STAD peptides are versatile cellular tools to selectively probe anchored type I PKA signaling events.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • A Kinase Anchor Proteins / antagonists & inhibitors*
  • A Kinase Anchor Proteins / chemistry
  • A Kinase Anchor Proteins / metabolism
  • Amino Acid Sequence
  • Binding Sites / drug effects
  • Cell Line, Tumor
  • Cell Membrane Permeability
  • Cyclic AMP-Dependent Protein Kinase Type I / antagonists & inhibitors*
  • Cyclic AMP-Dependent Protein Kinase Type I / chemistry
  • Cyclic AMP-Dependent Protein Kinase Type I / metabolism
  • Cyclic AMP-Dependent Protein Kinase Type II / antagonists & inhibitors*
  • Cyclic AMP-Dependent Protein Kinase Type II / chemistry
  • Cyclic AMP-Dependent Protein Kinase Type II / metabolism
  • Humans
  • Kinetics
  • Molecular Sequence Data
  • Peptides / chemistry*
  • Peptides / pharmacology
  • Phosphorylation
  • Protein Binding / drug effects
  • Protein Conformation
  • Protein Kinase Inhibitors / chemistry*
  • Protein Kinase Inhibitors / pharmacology
  • Protein Subunits / antagonists & inhibitors*
  • Protein Subunits / chemistry
  • Protein Subunits / metabolism

Substances

  • A Kinase Anchor Proteins
  • AKAP1 protein, human
  • Peptides
  • Protein Kinase Inhibitors
  • Protein Subunits
  • Cyclic AMP-Dependent Protein Kinase Type I
  • Cyclic AMP-Dependent Protein Kinase Type II