Pin-ing it down: Understanding the Enigmatic Role of Pin1 in Health and Disease

About the Project

Second Supervisor: Dr Gareth Hall, Institute of Structural and Chemical Biology & School of Biological and Biomedical Science, University of Leicester

Pin1 is a prolyl isomerase enzyme that catalyses the cis/trans isomerization of proline residues in over 200 protein substrates. Dysregulation of Pin1 levels is strongly associated with regulation of pathways associated with DNA repair and ageing. Consequently, the development of strategies to probe Pin1 function has gained significant interest. Despite efforts to design traditional small-molecule inhibitors that target Pin1’s catalytic domain, none have emerged as effective probes. Thus, there is a need to develop alternative approaches for inhibiting Pin1.

This project aims to define and exploit the mechanisms behind recently discovered covalent ligands that work together as ‘molecular crowbars’ to ‘pin’ Pin1 into an inactive state. This leads to Pin1 degradation in the cell. We will use an interdisciplinary approach in which mechanistic studies inform ligand design and synthesis.

Molecular crowbar mechanism: Using protein NMR in combination with biophysical analyses, including FRET-based biosensors, we will define the molecular events that lead to Pin1 destabilization. These experimental data sets will help us to understand the physics behind induced protein disorder. Ultimately, we will create a mechanistic model for how disorder of Pin1 is induced, and this will inform ligand design.

Ligand development: The structural data will be used to design and synthesise ‘bitopic’ ligands that contain two electrophilic sites. These ligands will mimic the dual-ligand covalent modification effect in a single drug-like molecule. In principle, this bivalent binding effect should lead to much greater potency (due to higher affinity), and selectivity because it must recognise two binding sites simultaneously. Ultimately, this work will deliver new small molecule inhibitors of Pin1 that will be validated in established cell models. This project will greatly advance drug development and fundamental understanding of Pin1 biology.

Techniques that will be undertaken during the project

• Structure based ligand design
• Protein NMR and X-ray crystallography
• Synthetic chemistry and small molecule characterisation
• Biophysical assays (e.g. FRET, fluorescence polarisation, isothermal titration calorimetry)
• Mass spectrometry
• Cell viability assays
• Western blotting and immunoprecipitation
• Computational tools e.g. AlphaFold3, BioPlex data set

Enquiries

Project Enquiries to r.g.doveston@leicester.ac.uk

To apply please use the application link at the bottom of this web page Chemistry | Postgraduate research | University of Leicester

Funding Notes

This project is only available on a self funded basis or if you have your own sponsorship.

References

10.1002/pro.5138; 10.1038/s41598-025-89342-0