Dynamic coacervation of a DNA Liquid

Dynamic condensation is one of many ways that gene expression is regulated. In this, RNA and proteins, the very products of gene expression, drive the phase separation of genes of different expression levels. However, a gene’s expression level and its state can change, causing the other, intertwined property to change as well. We aim to mimic this dynamic, self-regulating system using a model DNA liquid system that is transformed by RNA produced from in vitro transcription. This liquid is composed of DNA nanostars, four-armed star shaped structures created by the hybridization of four strands. Each arm ends in a palindromic, single-stranded sequence that allows nanostars to interact and condense into droplets which previous work has confirmed to share similar physical properties and spatial control as intracellular droplets (i.e., specific molecules are enriched or depleted in the droplet phase). We use confocal and fluorescence microscopy to track changes in the nanostar liquid system, like droplet size, with the creation of RNA transcripts.