Enzymatic regulation of the phase behavior of DNA nanostars

Inspired by the discovery of liquid-like condensates and their functions in living cells, recent theoretical studies have predicted various intriguing behaviors for phase-separating biomolecules subject to biochemical reactions, such as suppression of coarsening, droplet differentiation, and long-range spatial ordering. However, corresponding experimental studies remain limited. Here, we introduce a simple experimental model using DNA nanostars that involve enzymatically-controlled dimerization chemical reactions: non-phase-separating monomers exhibit a uniform fluid state, and transform into phase-separating dimers through an enzymatic reaction. The reaction kinetics and phase separation patterns can be characterized by gel electrophoresis and confocal microscopy observation, respectively. We discuss how phase separation behaviors change as a function of forward and backward reaction rates.