Understanding the rules of life

Bioscience for an integrated understanding of health

Category: Standard Studentships

Developing small molecule probes to investigate molecular recognition properties and apoptotic activity of p53 structural mutants

Project No.2201

Primary Supervisor

Dr Matthias Baud – University of Southampton

Co-Supervisor(s)

Prof John Spencer – University of Sussex

 

Summary

This project will lead the development of novel small molecule probes targeting a range of thermolabile p53-Y220X (tyr to e.g. cys/Ser/Asn/His) proteins.

These mutants display reduced thermal stability/activity in vitro/vivo and are implicated in over 150000 new cancer cases per annum worldwide. These probes will act as “molecular chaperones”, and exert their activity through potently binding at the surface of mutant proteins and induce their thermal stabilisation. This will provide critical new tools and opportunities for investigating the stability, molecular recognition properties, along with residual transcriptional and apoptotic activity of p53-Y220X proteins in cancer, with potential future implications for drug discovery and translational research. As a starting point, we have several hit molecular scaffolds, their high resolution crystal structures bound to the model mutant p53-Y220C, and preliminary SAR derived from cellular assays. The structure based design and chemical synthesis will be performed in the Spencer laboratory, which is equipped to industry standard with a range of microwaves, flow chemistry, and automated purification units. This will allow rapid access to large libraries of synthetic analogues for biophysical/biological evaluation and deriving robust structure-activity relationship data. Moreover, Spencer has just been appointed as Director of the Sussex Drug Discovery Centre so the student will be hosted in well-equipped, well-funded environment with a number of Research fellows and PhDs to help mentor them as well as the opportunity to attend group meetings and gain training in other areas of medicinal chemistry and cell biology. Biophysical/biochemical studies in the Baud lab will characterise the binding and molecular properties of the new molecules to p53-Y220X. This will provide key information and iterative feedback to refine the structure based molecular design/modelling (Glide docking), and synthesis of next generation/optimised probes. We have already established routine recombinant p53-Y220C production and optimised conditions for biophysical assays (ITC, NMR, DSF/DSC), logP/D/S determination

(HLPC/NMR), and serum stability (HPLC). JS and MB have an excellent track record in this area (see publications), and have already worked together and established collaborations in structural biology: Andreas Joerger (Frankfurt) is the world leading expert of mutant p53 structural biology, and Frank von Delft (Diamond) has pioneered high throughput X-ray protein crystallography at Diamond Light Source. Structural characterisation and binding mode validation of most potent in vitro leads at regular checkpoints will feedback to the modelling/synthesis, and inform “go/no-go” decisions.