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Exploring the binding of rationally engineered tandem-repeat proteins to E3 ubiquitin ligase Keap1.

ABSTRACT: The process of displaying functional peptides by 'grafting' them onto loops of a stable protein scaffold can be used to impart binding affinity for a target, but it can be difficult to predict the affinity of the grafted peptide and the effect of grafting on scaffold stability. In this study, we show that a series of peptides that bind to the E3 ubiquitin ligase Keap1 can be grafted into the inter-repeat loop of a consensus-designed tetratricopeptide repeat (CTPR) protein resulting in proteins with high stability. We found that these CTPR-grafted peptides had similar affinities to their free peptide counterparts and achieved a low nanomolar range. This result is likely due to a good structural match between the inter-repeat loop of the CTPR and the Keap1-binding peptide. The grafting process led to the discovery of a new Keap1-binding peptide, Ac-LDPETGELL-NH2, with low nanomolar affinity for Keap1, highlighting the potential of the repeat-protein class for application in peptide display.

SUBMITTER: Madden SK

PROVIDER: S-EPMC8660007 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Exploring the target scope of KEAP1 E3 ligase-based PROTACs.

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The Ubiquitin E3 Ligase TRIM21 Promotes Hepatocarcinogenesis by Suppressing the p62-Keap1-Nrf2 Antioxidant Pathway.

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The E3 ubiquitin ligase MARCH2 regulates ERGIC3-dependent trafficking of secretory proteins.

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Harnessing the E3 Ligase KEAP1 for Targeted Protein Degradation.

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