title: Allosteric activation of the protein kinase PDK1 with low molecular weight compounds.
abstract: Organisms rely heavily on protein phosphorylation to transduce intracellular signals. The phosphorylation of a protein often induces conformational changes, which are responsible for triggering downstream cellular events. Protein kinases are themselves frequently regulated by phosphorylation. Recently, we and others proposed the molecular mechanism by which phosphorylation at a hydrophobic motif (HM) regulates the conformation and activity of many members of the AGC group of protein kinases. Here we have developed specific, low molecular weight compounds, which target the HM/PIF-pocket and have the ability to allosterically activate phosphoinositide-dependent protein kinase 1 (PDK1) by modulating the phosphorylation-dependent conformational transition. The mechanism of action of these compounds was characterized by mutagenesis of PDK1, synthesis of compound analogs, interaction-displacement studies and isothermal titration calorimetry experiments. Our results raise the possibility of developing drugs that target the AGC kinases via a novel mode of action and may inspire future rational development of compounds with the ability to modulate phosphorylation-dependent conformational transitions in other proteins.
authors.affiliation: Research Group PhosphoSites, Department of Pharmaceutical and Medicinal Chemistry, University of Saarland, Saarbrücken, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Engel
authors.forename: Valerie
authors.initials: V
authors.lastname: Hindie
authors.forename: Laura A
authors.initials: LA
authors.lastname: Lopez-Garcia
authors.forename: Adriana
authors.initials: A
authors.lastname: Stroba
authors.forename: Francis
authors.initials: F
authors.lastname: Schaeffer
authors.forename: Iris
authors.initials: I
authors.lastname: Adrian
authors.forename: Jochen
authors.initials: J
authors.lastname: Imig
authors.forename: Leila
authors.initials: L
authors.lastname: Idrissova
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Nastainczyk
authors.forename: Stefan
authors.initials: S
authors.lastname: Zeuzem
authors.forename: Pedro M
authors.initials: PM
authors.lastname: Alzari
authors.forename: Rolf W
authors.initials: RW
authors.lastname: Hartmann
authors.forename: Albrecht
authors.initials: A
authors.lastname: Piiper
authors.forename: Ricardo M
authors.initials: RM
authors.lastname: Biondi
mesh_terms: D064413:3-Phosphoinositide-Dependent Protein Kinases; D000085:Acetates / Q000737:chemistry / Q000494:pharmacology*; D000494:Allosteric Regulation; D020816:Amino Acid Motifs; D001665:Binding Sites; D002478:Cells, Cultured; D015195:Drug Design; D004789:Enzyme Activation; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008970:Molecular Weight; D009154:Mutation; D010748:Phosphopeptides / Q000494:pharmacology; D010766:Phosphorylation; D011487:Protein Conformation; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry / Q000187:drug effects* / Q000235:genetics
chemical_list: D000085:Acetates; D010748:Phosphopeptides; C516425:S-(2-(4-chlorophenyl)-1-phenylethyl)thioglycolic acid; D064413:3-Phosphoinositide-Dependent Protein Kinases; C578562:PDPK1 protein, human; D017346:Protein Serine-Threonine Kinases