Exploring the RNA syntax for engineering therapeutic RNA-based nano-factories

描述(申请人提供)：小干扰siRNAs、核酶和反义RNAs等治疗剂在下调癌细胞或病毒感染细胞中特定基因表达的新分子方法中显示出巨大的潜力。因此，开发安全、高效、特异和非致病的纳米颗粒用于包装和递送多功能治疗性RNA是非常必要的。虽然可编程的RNA自组装已被证明有可能为实现这一目标提供解决方案，但基于RNA的多功能纳米结构的设计和工程的基本原理仍有待描述。这项建议的长期目标是促进基于RNA和核酸类似物的完全可控和多功能生物材料的开发，用于生物学研究、疾病诊断或治疗。为了实现这一挑战，该项目旨在产生对刺激响应的可编程三维(3D)超分子组件，控制其几何、拓扑、方向性和可寻址能力，并能够对环境的提示做出反应。例如，将合成可编程、可寻址和多功能的3D纳米笼，允许在3D空间中精确固定具有催化或识别特性的各种功能治疗模块，并通过AFM和低温电子显微镜等生化和生物物理方法进行表征。其中一些RNA纳米设备将被设计成在不同的超分子形状之间可逆地切换，以响应小的目标化合物。将研究协调和瞬时、时间激活的复杂功能的工程以及使用RNA结构模拟物(如锁定核酸(LNA))增强这些组件的化学稳定性的基本原理。这项工作将为控制涉及大量RNA分子的自组装过程提供新的见解，并将为设计具有强大生物学和医学潜力的基于RNA的复杂纳米机器铺平道路。预计该项目将为设计和开发多功能的治疗性RNA响应性载体奠定基本的组装和功能原则，这些载体将适用于体内应用，并符合未来的工业规模开发。

DESCRIPTION (provided by applicant): Therapeutic agents such as small interfering siRNAs, ribozymes, and anti-sense RNAs show significant potential in new molecular approaches to down-regulate specific gene expression in cancerous or viral- infected cells. The development of safe, efficient, specific and non-pathogenic nano-particles for the packaging and delivery of multifunctional therapeutic RNAs is thus highly desirable. While programmable RNA self-assembly has been shown to potentially provide a solution towards that goal, the underlying principles for the design and engineering of multifunctional nano-structures based on RNA have still to be delineated. The long-term goal of this proposal is to contribute to the development of fully controllable and versatile bio-materials based on RNA and nucleic acid analogs for use in the study of biology, disease diagnosis, or therapy. In order to achieve this challenge, this project aims at generating stimuli-responsive programmable three-dimensional (3D) supra-molecular assemblies with control over their geometry, topology, directionality and addressability and able to respond to the cues of the environment. For instance, programmable, addressable and multifunctional 3D nano-cages that allow precise immobilization in 3D space of various functional therapeutic modules with catalytic or recognition properties will be synthesized and characterized by biochemical and biophysical methods such as AFM and cryo electron microscopy. Some of these RNA nano-devices will be engineered to switch reversibly between distinct supra-molecular shapes in response to small target compounds. The principles underlying the engineering of concerted and transient, time-activated complex functions as well as the enhancement of the chemical stability of these assemblies using RNA structural mimics like locked-in nucleic acid (LNA) will be investigated. This work will provide new insights in the control of self-assembly processes involving large population of RNA molecules and will pave the way towards the design of complex RNA-based nano-machines with strong potential in biology and medicine. It is anticipated that this project will establish the fundamental assembly and functional principles for the design and development of versatile responsive vehicles for therapeutic RNAs that will be suitable for in vivo applications and amenable to industrial-scale development in the future.