סמינר לפיזיקה של מערכות ביולוגיות וחומרים רכים: Self-assembled DNA liquids: Active evaporation of micron-scale droplets

Abstract:

Biomolecules can self-assemble into liquid phases, termed ‘membraneless organelles’ in the biological context, though also known as ‘coacervates’. I will discuss our efforts to study this by exploiting DNA nanotechnology to create DNA particles that phase separate into liquids. Formation of liquids, rather than gel aggregates, depends sensitively on the internal flexibility of the DNA particles. The reduced valency of the particles, along with the relatively stiff nature of the constituent DNA strands, causes the liquid to be extraordinarily sparse, with a DNA volume fraction of only ~2%. This opens the possibility to activate the material by infusion of the liquid with proteins. I will discuss recent efforts to exploit this to force droplets of DNA liquids to evaporate through the action of proteins that actively degrade the DNA.