Abstract

Condensates spatially partition the complex cellular interior using genetically encoded interactions between various biomolecules. Yet, to fulfill countless cellular functions, condensates also need to form at the right time, at the right position, and with the right size. I will demonstrate how driven chemical reactions enable such control. Based on thermodynamic constraints, I will show that reactions involving the droplet material must be driven out of equilibrium, e.g., by consuming ATP . Then, enzymes concentrated inside or outside the droplet can create compositional gradients that affect droplet nucleation, shape, and position. Interestingly, the length scale associated with this reaction-diffusion system governs droplet size and spacing, akin to Turing patterns. I will make this analogy more precise by discussing Turing patterns with physical interactions, i.e., non-ideal diffusion. In summary, I will discuss the intertwined physics of non-ideal diffusion and chemical reactions, which is relevant beyond Biology.