An Integrated Molecular Grafting Approach for the Design of Keap1-Targeted Peptide Inhibitors
Huawu Yin1, Yen-Hua Huang1, Sarah A Best2,3
1Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland 4072, Australia.
ACS Chemical Biology
|June 21, 2021
Summary
We engineered a peptide to inhibit the Nrf2:Keap1 interaction, a key target for oxidative stress diseases. This novel peptide shows improved stability, cellular uptake, and gene expression, offering a promising therapeutic strategy.
Area of Science:
- Biochemistry
- Molecular Biology
- Drug Discovery
Background:
- The Nrf2:Keap1 interaction is a critical target for treating diseases associated with oxidative stress.
- Current therapeutic strategies face challenges due to the poor stability and limited cellular uptake of Nrf2-derived inhibitors.
- Developing stable and cell-penetrant peptide inhibitors is crucial for effective treatment.
Purpose of the Study:
- To engineer a novel peptide inhibitor targeting the Nrf2:Keap1 interaction with enhanced stability and cellular uptake.
- To create a multifunctional molecular entity by grafting an Nrf2 motif onto a cyclotide scaffold.
- To validate the therapeutic potential of the engineered peptide in modulating cytoprotective gene expression.
Main Methods:
- Utilized a molecular grafting strategy to combine an Nrf2 motif, engineered disulfide bond, and cell-penetrating peptide onto a cyclotide scaffold (MCoTI-II).
- Characterized the resulting peptide (MCNr-2c) for its affinity to Keap1, conformational rigidity, cellular uptake, and resistance to proteolysis.
- Assessed the ability of MCNr-2c to enhance the intracellular expression of Nrf2-target genes (NQO1 and TALDO1).
Main Results:
- The engineered peptide MCNr-2c demonstrated nanomolar affinity for Keap1 due to enhanced conformational rigidity.
- MCNr-2c exhibited improved cellular uptake and significantly increased expression of Nrf2-target genes.
- The grafted peptide inherited the scaffold's stability, showing resistance to proteolysis in serum.
Conclusions:
- The integrated molecular grafting strategy successfully created a multifunctional peptide inhibitor (MCNr-2c) targeting the Nrf2:Keap1 interaction.
- MCNr-2c represents a proof-of-concept for a novel therapeutic approach to oxidative stress-related diseases.
- This approach holds broad potential for designing peptide drug leads with multiple functionalities and improved biopharmaceutical properties.
