Redox-Inactive Peptide Disrupting Trx1-Ask1 Interaction for Selective Activation of Stress Signaling

Biochemistry. 2018 Feb 6;57(5):772-780. doi: 10.1021/acs.biochem.7b01083. Epub 2018 Jan 5.


Thioredoxin 1 (Trx1) and glutaredoxin 1 (Grx1) are two ubiquitous redox enzymes that are central for redox homeostasis but also are implicated in many other processes, including stress sensing, inflammation, and apoptosis. In addition to their enzymatic redox activity, a growing body of evidence shows that Trx1 and Grx1 play regulatory roles via protein-protein interactions with specific proteins, including Ask1. The currently available inhibitors of Trx1 and Grx1 are thiol-reactive electrophiles or disulfides that may suffer from low selectivity because of their thiol reactivity. In this report, we used a phage peptide library to identify a 7-mer peptide, 2GTP1, that binds to both Trx1 and Grx1. We further showed that a cell-permeable derivative of 2GTP1, TAT-2GTP1, disrupts the Trx1-Ask1 interaction, which induces Ask1 phosphorylation with subsequent activation of JNK, stabilization of p53, and reduced viability of cancer cells. Notably, as opposed to a disulfide-derived Trx1 inhibitor (PX-12), TAT-2GTP1 was selective for activating the Ask1 pathway without affecting other stress signaling pathways, such as endoplasmic reticulum stress and AMPK activation. Overall, 2GTP1 will serve as a useful probe for investigating protein interactions of Trx1.

Publication types

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

MeSH terms

  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / pharmacology
  • Cell Line, Tumor
  • Cell Membrane Permeability
  • Cell Survival / drug effects
  • Drug Screening Assays, Antitumor
  • Endoplasmic Reticulum Stress / drug effects
  • Enzyme Activation / drug effects
  • Enzymes, Immobilized
  • Glutaredoxins
  • HEK293 Cells
  • Humans
  • MAP Kinase Kinase Kinase 5 / antagonists & inhibitors*
  • MAP Kinase Kinase Kinase 5 / chemistry
  • MAP Kinase Kinase Kinase 5 / physiology
  • MAP Kinase Signaling System / drug effects*
  • NADP / analysis
  • Oligopeptides / isolation & purification
  • Oligopeptides / pharmacology*
  • Oxidation-Reduction
  • Peptide Library*
  • Phosphorylation / drug effects
  • Protein Binding / drug effects
  • Protein Interaction Mapping
  • Protein Processing, Post-Translational / drug effects
  • Reactive Oxygen Species / metabolism
  • Recombinant Proteins / metabolism
  • Stress, Physiological / physiology*


  • Antineoplastic Agents
  • Enzymes, Immobilized
  • GLRX protein, human
  • Glutaredoxins
  • Oligopeptides
  • Peptide Library
  • Reactive Oxygen Species
  • Recombinant Proteins
  • NADP
  • MAP Kinase Kinase Kinase 5
  • MAP3K5 protein, human