Periodic Reporting for period 1 - DREAM (DNA-encoded REconfigurable and Active Matter)
Période du rapport: 2023-09-01 au 2026-02-28
This project aims to bridge this gap by using DNA as a molecular program to give synthetic materials some of these life-like properties. More specifically, the goal is to develop DNA-encoded principles that would allow synthetic soft materials to adapt, evolve, and perform dynamic functions in way similar to what living systems do. To reach this goal, we will develop a new way for DNA molecules to dynamically assemble themselves at room or biological temperature, a process called isothermal and reconfigurable DNA self-assembly. This will enable the construction of miniature structures made out of DNA, such as so-called DNA origamis or nanotubes, which can change their shape or behavior autonomously, or when triggered by external stimuli like light. By attaching proteins to these dynamic and evolutive DNA scaffolds, we plan to design more complex artificial systems that can mimic biological processes. These will include synthetic metabolic pathways that can carry out useful chemical reactions, or programmable catalytic switches that turn specific activities on and off. We will also develop a novel way to discover optimal nanostructures by evolution, allowing useful structures to emerge through iterative self-selection steps. To get more macroscopic properties, the project will integrate gene-containing DNA into materials rich in interfaces, such as liquid films, droplets, emulsions or lab-on-chip systems. This will make it possible to genetically program how these materials will behave. More specifically, using reconstituted cell-free expression systems, the materials themselves will produce interfacially active proteins, which will in turn control their surface tension and dynamic properties. Following this way, we hope to realize new kinds of behavior, such as genetically driven flows, self-propelling droplets, or autonomous sorting systems. By co-expressing functional proteins such as enzymes or antibodies, we plan to ultimately create multifunctional materials that can grow, move, sense, adapt, recognize and/or react, demonstrating in fine the power and versatility of using DNA as a universal code for programming life-like functions in smart synthetic materials.
1. Ultra-fast DNA self-assembly inside living cells
DNA is not only the support of our genetic code, it can also serve as a building material for nanoscale structures, such as so-called DNA origamis. Traditionally, creating such refined structures requires high temperatures and chemical conditions incompatible with life, meaning they must be fabricated separately and later introduced into cells. In this project, we have developed a gentle, isothermal method allowing DNA origamis to self-assemble in biological media at body temperature (37 °C). Even more remarkably, the process happens in just a few minutes, which constitutes a neat improvement over conventional methods taking over hours to days. Using these new conditions, we have demonstrated for the first time 2D and 3D DNA origamis that self-assemble directly in the presence of living cells and tissues. This breakthrough opens new horizons for building nanomachines that form, adapt, interact and operate in situ with living systems.
2. Genetic control of surface tension and liquid motion
We have also demonstrated that the physical behavior of liquids can be programmed by DNA, not through its self-assembly but a genetic level. Instead of relying on chemical additives to modify surface tension, as it is usually done, we have used a synthetic gene encoding for interfacially active proteins called hydrophobins and expressed them with a cell-free system. The expressed proteins lowered surface tension, allowing us to control fluid behavior through gene activity. By adjusting gene expression, we could fine-tune surface dynamics over time and even generate controllable liquid motion, constituting the first-ever demonstration of genetically encoded liquid transport.