Light-actuated synthetic coacervates as organelle models – LASCO2

Cellular compartmentalization is crucial to the spatiotemporal coordination of biological functions. Membraneless organelles formed by liquid-liquid phase separation (coacervation) dynamically compartmentalize biomolecules in cells by being formed and dissolved in response to stimuli. Micro-droplets produced in vitro by complex coacervation of polyelectrolytes are now being used as synthetic membraneless organelles. Coacervate droplets recapitulate essential features of membraneless organelles; yet, it remains challenging to precisely control their formation and dissolution. New coacervate platforms are required to achieve improved spatiotemporal control. In this project, we will develop photo-responsive coacervate droplets capable of being formed and dissolved in response to light stimuli. We will first rationalize the mechanism and driving forces of photoswitchable coacervation, and the associated uptake/release of guest solutes. We will then demonstrate that photoswitchable coacervates can be exploited for the reversible photocontrol of (bio)chemical reactions and self-assembly processes to mimic membraneless organelles' functions. Overall, the project will establish new approaches to apply the spatiotemporal precision of light to practical systems relevant to the emerging fields of synthetic biology and systems chemistry.