Inhibition of CREB phosphorylation by conjugates of adenosine analogues and arginine-rich peptides, inhibitors of PKA catalytic subunit

Chembiochem. 2015 Jan 19;16(2):312-9. doi: 10.1002/cbic.201402526. Epub 2014 Dec 8.


Bisubstrate inhibitors of protein kinases associate simultaneously with two substrate-binding sites of the kinase and thus potentially possess better inhibitory potency and selectivity than inhibitors binding to only the conserved ATP-site of the kinase. We have previously used conjugates of adenosine analogues and arginine-rich peptides (ARCs) to develop proteolytically stable cell plasma membrane-permeable bisubstrate inhibitors whose biochemical affinities towards several basophilic protein kinases of the AGC group are in the picomolar range. The potency of bisubstrate inhibitors to affect the phosphorylation of proteins in living cells has been described in a limited number of publications. In this study, the effect of ARCs on the protein kinase A (PKA)-catalysed cAMP response element-binding protein (CREB) phosphorylation pathway was studied in living mammalian cells. Our results demonstrate that at low micromolar extracellular concentration N-myristoylated ARCs are capable of reducing the activity of transcription factor CREB through inhibition of PKA.

Keywords: CREB; inhibitors; nucleoside-peptide conjugates; phosphorylation; protein kinase A.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine / analogs & derivatives*
  • Adenosine / chemistry
  • Animals
  • Arginine
  • CHO Cells
  • Catalytic Domain
  • Cricetulus
  • Cyclic AMP Response Element-Binding Protein / metabolism*
  • Cyclic AMP-Dependent Protein Kinases / antagonists & inhibitors*
  • Cyclic AMP-Dependent Protein Kinases / metabolism
  • HEK293 Cells / drug effects
  • Humans
  • Immunoblotting
  • Inhibitory Concentration 50
  • Luciferases / genetics
  • Peptides / chemistry*
  • Peptides / pharmacology
  • Phosphorylation / drug effects
  • Protein Kinase Inhibitors / chemistry*
  • Protein Kinase Inhibitors / pharmacology*


  • CREB1 protein, human
  • Cyclic AMP Response Element-Binding Protein
  • Peptides
  • Protein Kinase Inhibitors
  • Arginine
  • Luciferases
  • Cyclic AMP-Dependent Protein Kinases
  • Adenosine