DEVELOPMENT OF A HIGH RESOLUTION PROXIMITY LABELING PLATFORM FOR THE MAPPING OF NANOSCALE PROTEIN ENVIRONMENTS

Abstract

Advances in chemoproteomic technologies over recent decades haverevolutionized the discovery and development of therapeutics. In particular, the advent of proximity labeling platforms (PLPs), has enabled the elucidation of biomolecular interaction networks, and thus the discovery of therapeutically relevant protein-protein interactions (PPIs). While these platforms have been foundational in the spatiotemporal mapping of subcellular interactomes, their diffuse spatial resolution has largely precluded their application to the study of nanometer-scale systems, or microenvironments. Given that many important interactomes and PPIs transpire on a low nanometer distance scale, technologies that could resolve biological information at such resolution are urgently needed and would be transformative across biology. This thesis describes the development of a photocatalytic proximity labeling platform (µMap) that achieves low-nanometer labeling resolution. This precise spatial resolution is confirmed by STED super-resolution microscopy (Chapter 3). The successful application of this platform to the study of cell surface immunomodulatory clusters(Chapter 2) and the mapping of small molecule protein binding sites (Chapter 4) is described.