p53PRISM: Regulation of life-and-death decisions by conformational switches
Lead Research Organisation:
King's College London
Department Name: Chemistry
Abstract
The protein p53 guards against cancer by orchestrating the self-destruction of precancerous cells. Accordingly, p53 in most cancers is
malfunctioning and permits the unchecked cellular growth central to the disease. Understanding the molecular mechanisms
underlying p53's function is thus crucial, and researchers now know that p53 is regulated in part by a plethora of post-translational
modifications (PTMs).
In this project, I will investigate the functional consequences in p53 of an atypical PTM: the reorientation of a protein's backbone by
the isomerisation of a proline between cis and trans stereoisomers (Pro-Iso). Specifically, I hypothesise Pro-Iso acts as a
"conformational switch" which drives p53 into distinct functional states. This hypothesis is untested due to the difficulty of obtaining
chemically well-defined p53 variants and p53's recalcitrance towards structural biology techniques.
To overcome these challenges, I will explore the role of Pro-Iso in p53's function via an interdisciplinary chemical biology and
biophysical approach. First, I will use the protein semisynthesis techniques pioneered by my supervisor Dr. Manuel Müller (King's
College London) to produce full-length p53 variants bearing precise chemical modifications that probe different aspects of Pro-Iso.
Second, I will subject these variants to a host of biochemical assays to ascertain differences in key properties and functions. Finally, I
will use single-molecule Förster resonance energy spectroscopy to investigate the effect of Pro-Iso on the conformational dynamics
underlying p53's molecular interactions.
This project will provide me with the transferable skills, training and track record needed to pursue a career as an independent
research group leader. More importantly, this research will help further decode how p53 makes cellular life-and-death decisions and
thus expand the knowledgebase from which global stakeholders seek to tackle growing cancer rates in an aging world.
malfunctioning and permits the unchecked cellular growth central to the disease. Understanding the molecular mechanisms
underlying p53's function is thus crucial, and researchers now know that p53 is regulated in part by a plethora of post-translational
modifications (PTMs).
In this project, I will investigate the functional consequences in p53 of an atypical PTM: the reorientation of a protein's backbone by
the isomerisation of a proline between cis and trans stereoisomers (Pro-Iso). Specifically, I hypothesise Pro-Iso acts as a
"conformational switch" which drives p53 into distinct functional states. This hypothesis is untested due to the difficulty of obtaining
chemically well-defined p53 variants and p53's recalcitrance towards structural biology techniques.
To overcome these challenges, I will explore the role of Pro-Iso in p53's function via an interdisciplinary chemical biology and
biophysical approach. First, I will use the protein semisynthesis techniques pioneered by my supervisor Dr. Manuel Müller (King's
College London) to produce full-length p53 variants bearing precise chemical modifications that probe different aspects of Pro-Iso.
Second, I will subject these variants to a host of biochemical assays to ascertain differences in key properties and functions. Finally, I
will use single-molecule Förster resonance energy spectroscopy to investigate the effect of Pro-Iso on the conformational dynamics
underlying p53's molecular interactions.
This project will provide me with the transferable skills, training and track record needed to pursue a career as an independent
research group leader. More importantly, this research will help further decode how p53 makes cellular life-and-death decisions and
thus expand the knowledgebase from which global stakeholders seek to tackle growing cancer rates in an aging world.
