title: Peptide inhibitors of the Keap1-Nrf2 protein-protein interaction.
abstract: Disruption of the interaction between the ubiquitination facilitator protein Keap1 and the cap'n'collar basic-region leucine-zipper transcription factor Nrf2 is a potential strategy to enhance expression of antioxidant and free radical detoxification gene products regulated by Nrf2. Agents that disrupt this protein-protein interaction may be useful pharmacological probes and future cancer-chemopreventive agents. We describe the structure-activity relationships for a series of peptides based upon regions of the Nrf2 Neh2 domain, of varying length and sequence, that interact with the Keap1 Kelch domain and disrupt the interaction with Nrf2. We have also investigated sequestosome-1 (p62) and prothymosin-α sequences that have been reported to interact with Keap1. To achieve this we have developed a high-throughput fluorescence polarization (FP) assay to screen inhibitors. In addition to screening synthetic peptides, we have used a phage display library approach to identify putative peptide ligands with non-native sequence motifs. Candidate peptides from the phage display library screening protocol were evaluated in the FP assay to quantify their binding activity. Hybrid peptides based upon the Nrf2 "ETGE" motif and the sequestosome-1 "Keap1-interaction region" have superior binding activity compared to either native peptide alone.
authors: Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, London WC1N 1AX, UK.
authors: Rowena
authors: R
authors: Hancock
authors: Hélène C
authors: HC
authors: Bertrand
authors: Tadayuki
authors: T
authors: Tsujita
authors: Shama
authors: S
authors: Naz
authors: Ayman
authors: A
authors: El-Bakry
authors: Jitnueng
authors: J
authors: Laoruchupong
authors: John D
authors: JD
authors: Hayes
authors: Geoff
authors: G
authors: Wells
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D001667:Binding, Competitive; D004354:Drug Screening Assays, Antitumor; D004926:Escherichia coli; D005454:Fluorescence Polarization; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000737:chemistry* / Q000378:metabolism; D000072019:Kelch-Like ECH-Associated Protein 1; D051379:Mice; D008969:Molecular Sequence Data; D051267:NF-E2-Related Factor 2 / Q000096:biosynthesis / Q000737:chemistry*; D009842:Oligopeptides / Q000737:chemistry*; D019151:Peptide Library; D011485:Protein Binding; D011498:Protein Precursors / Q000737:chemistry; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000737:chemistry; D000071456:Sequestosome-1 Protein; D013947:Thymosin / Q000031:analogs & derivatives / Q000737:chemistry
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D047908:Intracellular Signaling Peptides and Proteins; C431364:KEAP1 protein, human; D000072019:Kelch-Like ECH-Associated Protein 1; D051267:NF-E2-Related Factor 2; C495636:Nfe2l2 protein, mouse; D009842:Oligopeptides; D019151:Peptide Library; D011498:Protein Precursors; D011993:Recombinant Fusion Proteins; C099718:SQSTM1 protein, human; D000071456:Sequestosome-1 Protein; C040782:prothymosin alpha; D013947:Thymosin