Nanosensing protein allostery using a bivalent mouse double minute two (MDM2) assay

Area of Science:

• Biochemistry
• Nanotechnology
• Chemical Biology

Background:

• The tumor suppressor protein p53 is critical in cancer, often inactivated by MDM2.
• Targeting the MDM2-p53 interaction is a key strategy for cancer therapy.
• Current tools for studying this interaction are limited, hindering drug discovery.

Purpose of the Study:

• To develop a novel nanosensing assay for investigating the full-length MDM2-p53 interaction.
• To provide an allosteric assay for identifying binding ligands of the MDM2-p53 complex.
• To establish a solution-based method for studying protein-protein interactions using nanoparticles.

Main Methods:

• Utilized surface-enhanced Raman scattering (SERS)-active nanoparticles functionalized with a p53 peptide mimic (peptide 12.1).
• Observed nanoparticle aggregation upon addition of full-length MDM2 protein, indicating specific binding.
• Demonstrated competitive inhibition of nanoparticle assembly by known MDM2-binding ligands (peptide 12.1 and Nutlin-3).

Main Results:

• Successfully developed a SERS-based nanosensing approach to monitor MDM2-p53 interactions in solution.
• Showcased specific, biologically relevant nanoparticle aggregation driven by protein-peptide binding.
• Validated the assay's ability to identify and characterize MDM2-binding ligands.

Conclusions:

• The developed nanosensing assay enables robust investigation of full-length MDM2-p53 interactions.
• This platform serves as a valuable tool for screening and identifying novel therapeutic agents targeting the MDM2-p53 pathway.
• The study demonstrates the potential of SERS-based nanoparticle assembly for studying protein interactions in biochemical research.