Department of Bioengineering , University of California at Riverside , Riverside , California 92521 , United States.
Department of Bioengineering , California Institute of Technology , Pasadena , California 91125 , United States.
ACS Nano. 2019 May 28;13(5):5214-5221. doi: 10.1021/acsnano.8b09421. Epub 2019 Apr 22.
RNA is a functionally rich and diverse biomaterial responsible for regulating several cellular processes. This functionality has been harnessed to build predominately small nanoscale structures for drug delivery and the treatment of disease. The understanding of design principles to build large RNA structures will allow for further control of stoichiometry and spatial arrangement drugs and ligands. We present the design and characterization of RNA nanotubes that self-assemble from programmable monomers, or tiles, formed by five distinct RNA strands. Tiles include double crossover junctions and assemble via single-stranded sticky-end domains. We find that nanotube formation is dependent on the intertile crossover distance. The average length observed for the annealed RNA nanotubes is ≈1.5 μm, with many nanotubes exceeding 10 μm, enabling the characterization of RNA nanotubes length distribution via fluorescence microscopy. Assembled tubes were observed to be stable for more than 24 h, however post-annealing growth under isothermal conditions does not occur. Nanotubes assemble also from RNA tiles modified to include a single-stranded overhang (toehold), suggesting that it may be possible to decorate these large RNA scaffolds with nanoparticles or other nucleic acid molecules.
RNA 是一种功能丰富且多样的生物材料，负责调节多种细胞过程。这种功能已被用于构建主要为小纳米尺度结构的药物输送和疾病治疗。了解构建大型 RNA 结构的设计原则将允许进一步控制药物和配体的化学计量和空间排列。我们提出了一种 RNA 纳米管的设计和表征方法，该纳米管由可编程单体（或由 5 个不同的 RNA 链组成的“瓦片”）自组装而成。瓦片包括双交叉连接，并通过单链粘性末端域组装。我们发现，纳米管的形成取决于瓦片之间的交叉距离。退火后的 RNA 纳米管的平均长度约为 1.5 μm，许多纳米管超过 10 μm，这使得可以通过荧光显微镜对 RNA 纳米管的长度分布进行表征。组装后的管在 24 小时以上的时间内保持稳定，然而在等温条件下退火后不会发生生长。包括单链突出物（钉位）的 RNA 瓦片也可以组装成纳米管，这表明可以用纳米颗粒或其他核酸分子来修饰这些大型 RNA 支架。
