Dynamic Artificial Organelles Controlled by an Enzymatic Network

Compartmentalisation of biochemical reactions into organelles is a key mechanism of organization in many cells. An important fraction of organelles lacks a membrane boundary but is formed by condensation of macromolecules. As a consequence, these membraneless organelles provide a unique microenvironment in which biomolecules can be concentrated and their reactions modulated.

Cells can control the assembly and disassembly of membraneless organelles by enzymatic processes, but similar control has not been achieved in vitro yet. Here we develop a minimal enzymatic network that fully controls the fate of artificial membraneless organelles consisting of ATP-based coacervate droplets. Droplet condensation and disassembly is dynamic and reversible, triggered by the addition of the enzymatic substrates and completed within minutes. We show how these artificial organelles can be used to sequester, fold and assemble RNA, and to protect it from degradation. These model artificial organelles ultimately help us to create a better understanding of the principles of cellular organization and to unravel the potential role of biomolecular condensates in the origin of life.