Light-controlled growth of DNA organelles in synthetic cells
Light-controlled growth of DNA organelles in synthetic cells
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DOI：
10.1098/rsfs.2023.0017
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发表时间：
2023-08-11
期刊：
影响因子：
4.4
通讯作者：
Franco，Elisa
中科院分区：
文献类型：
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作者：
Agarwal，Siddharth;Dizani，Mahdi;Franco，Elisa
活细胞通过动态的无膜隔室调节其许多重要功能，这些隔室在响应不同类型的刺激时相分离（凝聚）。在合成细胞中，反应性冷凝物同样可以在维持其运作方面发挥关键作用。在这里，我们使用DNA纳米技术来设计和表征对光有反应的人工冷凝物。这些凝聚体是通过星形DNA亚基（纳米星）的可编程相互作用形成的，它们被设计成包括光响应保护域。在没有紫外线照射的情况下，纳米星相互作用不利于凝析油的形成。紫外线照射劈裂了保护结构域，增加了纳米星的价并使其凝结。我们证明，这种方法可以通过给药紫外线暴露时间精确地调整凝聚物形成的动力学。我们的实验观察得到了一个计算模型的补充，该模型描述了不同价粒子混合物在混合物组成和键相互作用能变化下的相变。此外，我们还说明了紫外线活化如何成为一种有用的工具，以控制乳化液液滴中DNA凝聚物的形成和大小，作为合成细胞中的原型细胞器。这项研究扩展了我们通过物理刺激远程控制dna成分动态的能力，尤其与最小人工细胞和反应性生物材料的开发相关。
Living cells regulate many of their vital functions through dynamic, membraneless compartments that phase separate (condense) in response to different types of stimuli. In synthetic cells, responsive condensates could similarly play a crucial role in sustaining their operations. Here we use DNA nanotechnology to design and characterize artificial condensates that respond to light. These condensates form via the programmable interactions of star-shaped DNA subunits (nanostars), which are engineered to include photo-responsive protection domains. In the absence of UV irradiation, the nanostar interactions are not conducive to the formation of condensates. UV irradiation cleaves the protection domains, increases the nanostar valency and enables condensation. We demonstrate that this approach makes it possible to tune precisely the kinetics of condensate formation by dosing UV exposure time. Our experimental observations are complemented by a computational model that characterizes phase transitions of mixtures of particles of different valency, under changes in the mixture composition and bond interaction energy. In addition, we illustrate how UV activation is a useful tool to control the formation and size of DNA condensates in emulsion droplets, as a prototype organelle in a synthetic cell. This research expands our capacity to remotely control the dynamics of DNA-based components via physical stimuli and is particularly relevant to the development of minimal artificial cells and responsive biomaterials.