Development of a Combined Fluorescence, Optical Diffraction Tomography and Brillouin (FOB) Microscope for the Quantitative Investigation of Phase Transitions in Cells
This project led by the Alberti and Guck teams will develop a new combined fluorescence, optical diffraction tomography and Brillouin (FOB) microscope and to use FOB microscopy to study physiological and pathological phase transitions in vitro and in vivo. FOB microscopy will permit the quantitative imaging of 3D distributions of mass density, longitudinal modulus and viscosity inside living cells and with optical resolution. We will first build the FOB microscope and identify the physical signatures associated with phase transitions of synthetic systems, then verify these signatures in prion-like protein droplets in vitro, and finally use FOB microscopy to study the connection between phase transitions of these proteins and functional changes in cultured cells and in motor neurons. The quantitative characterization of condensates formed by wild-type and mutant proteins will reveal the connection between physical signatures measured by FOB microscopy, the molecular mechanisms underlying their conversion from a physiological to an aberrant disease-causing state, and the ultimate functional changes leading to disease pathology.