Development of a fluorogenic chemogenetic dimerization technology for controlling, imaging & sensing protein proximity – CATCHFIRE

Proximity between proteins plays an essential and ubiquitous role in many biological processes. Molecular tools enabling to control and observe the proximity of proteins are thus essential for studying the functional role of physical distance between two proteins. In this context, chemically induced proximity (CIP) technologies have been transformative for studying the role of protein proximity in cellular and physiological mechanisms. Based on the genetic fusion of proteins to dimerization domains that interact in a specific manner in presence of a small chemical inducer of proximity, CIP technologies enable to modulate protein interactions and thus biological processes with high temporal control. In this project we propose to develop a chemically induced proximity technology with intrinsic fluorescence imaging and sensing capabilities for real-time monitoring of proximity. The developed technology will rely on genetic fusion to small dimerizing domains that interact together in presence of fluorogenic inducers of proximity that fluoresce upon formation of the ternary assembly, allowing real-time monitoring of chemically induced proximity. This technology should be game-changing as it will open a wide range of possibilities to study the role of protein proximity in biology and control biological processes for biological/medical applications. We will demonstrate our ability to regulate and track biochemical and cellular processes through various mechanisms including regulated localization/compartmentalization of proteins regulated transport of organelles. In addition, we will show that the intrinsic imaging/sensing capabilities of the system provide unprecedented opportunities to design sensors of cell signaling and cell physiology, and image and control endogenous proteins.