Seminar “Self-assembly processes of living organisms and ‘membraneless organelles”
Date
Thursday, 12th April 2018
Time
4:00 pm
Place
University of Barcelona
Faculty of Physics Building
Room 3.20, 3rd floor
Speaker
Dr Omar A. Saleh, UC Santa Barbara (USA)
Abstract
Living organisms create a variety of complex materials through self-assembly processes, in which soft biomacromolecules (e.g. nucleic acids, proteins) form functional structures through non-covalent binding interactions. Recently, there has been interest in the formation of liquid droplets of biomacromolecules, frequently called ‘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.
Our engineered system displays unusual properties, including the ability to create several distinct liquid phases in a single solution, and to tailor interactions between the phases. Further, the reduced valency of the particles, along with the relatively stiff nature of the constituent DNA strands, causes the liquid to be extraordinarily sparse: the DNA volume fraction is only ~2%. This opens the possibility to activate the material by infusion of the liquid with proteins; I will discuss our initial attempts at doing this.
