Spatial and topological control of receptor signaling using DNA nanotechnology

Chou小组的研究项目探索了自组装纳米器件的设计原理。我们目前专注于开发DNA作为3D纳米纤维的介质，以及用脂质，聚合物，蛋白质将工程DNA纳米结构功能化，使其与生物系统连接。这些DNA支架纳米结构在合成纳米材料中是独一无二的，因为它们的性质是序列可编程的，这使得能够精确控制它们的结构和动力学。我们的团队正在利用这些能力来构建纳米器件，这些纳米器件与细胞膜受体连接，以操纵细胞信号通路。我们特别感兴趣的是通过大规模接触触发的信号通路，如细胞与细胞和细胞与病原体的相互作用。这些相互作用诱导的细胞活化状态不同于使用可溶性配体诱导的那些，但特别难以合成概括，因为它们涉及异源多价受体-配体相互作用以及它们在质膜上的剧烈空间重组。利用DNA纳米技术的可编程性，NSERC的这一提议旨在构建一种能够对这种多价受体-配体相互作用进行空间控制的人工细胞膜。具体目标是：（1）建立通过将DNA纳米结构与脂质、聚合物、蛋白质和微球组合来制造人工细胞膜的方法学;（2）理解生物流体（例如血清）如何影响人工细胞膜的特征;（3）评估人工细胞膜根据其设计特征切换细胞信号传导的能力;（4）证明通过在人工细胞膜上展示异源多价配体阵列来增强细胞信号传导的能力。该成果将推进细胞信号传导生物学的知识，产生可编程的细胞界面材料，供生物物理学，合成生物学和生物医学工程界使用，并导致下一代细胞制造技术和指导细胞命运的离体和体内。

The Chou group's research program explores design principles of self-assembling nanoscale devices. We currently focus on developing DNA as a medium for 3D nanofabrication, and on functionalizing engineered DNA nanostructures with lipids, polymers, proteins to interface them with biological systems. These DNA-scaffolded nanostructures are unique among synthetic nanomaterials in that their properties are sequence-programmable, which enables exquisite control over their structure and dynamics. Our group is using these capabilities to construct nanodevices that interface with cell membrane receptors for manipulating cell signaling pathways. Of particular interest to us are signaling pathways triggered through large-scale contacts, such as cell-cell and cell-pathogen interactions. These interactions induce cell activation states distinct from those induced using soluble ligands, but are especially difficult to recapitulate synthetically because they involve hetero-multivalent receptor-ligand interactions as well as their drastic spatial re-organization on the plasma membrane. Leveraging the programmability of DNA nanotechnology, this NSERC proposal aims to build an artificial cell membrane capable of spatial control over such multivalent receptor-ligand interactions. The specific aims are to: (1) establish the methodology of manufacturing an artificial cell membrane by combining DNA nanostructures with lipids, polymers, proteins, and microspheres; (2) understand how biological fluids, such as serum, influence features of the artificial cell membrane; (3) assess ability of the artificial cell membrane to toggle cell signaling as a function of its design features; (4) demonstrate ability to potentiate cell signaling via display of hetero-multivalent ligand arrays on the artificial cell membrane. The outcome will advance knowledge of cell signaling biology, generate a programmable cell-interfacing material for use by the biophysics, synthetic biology, and biomedical engineering community, and lead to next-generation technologies for cell manufacturing and for directing cell fate ex vivo and in vivo.