Biochemical Networks for Controlling the Growth and Metamorphosis of Soft Materials

Complex cellular behaviors such as motion and division are directed by far-from-equilibrium chemical networks that regulate the assembly and reconfiguration of a cell’s architecture at the molecular scale. The ability to program the evolution of synthetic materials using designed chemical networks in fashions similar to the way biological networks regulate a cell and tissue architecture could be a route to building radically new materials that could grow into specific shapes, heal, or adapt to their environments. Building and improving these systems might also provide new perspectives on the structural organization of cells and tissues and on the genetic and signal transduction networks that regulate these cell and tissues’ structures and therefore, functions. We have been developing synthetic components that dynamically assemble and change the shapes of biomolecular materials, specifically hydrogels and semiflexible polymer networks, and corresponding synthetic chemical networks that can regulate these materials’ dynamic assembly. I will describe how different biomolecular signals can induce different dynamic polymerization and depolymerization processes in these materials and how chemical networks can be coupled to these materials to induce dynamic material behavior. To understand what new behaviors can arise in these systems when their chemical networks become large and complex, we have recently developed integrated synthetic in vitro genetic regulatory networks consisting of oligonucleotide templates, T7 RNA polymerase and an RNase. These networks can consist of tens of different interconnected network elements and could be used to build synthetic regulatory networks of complexities comparable to those of simple viruses or those that construct macromolecular complexes inside cells.