Abstract：
Biological nanopores crucially control the import and export of biomolecules across lipid membranes in cells. They have found widespread use in biophysics and biotechnology, where their typically narrow, fixed diameters enable selective transport of ions and small molecules, as well as DNA and peptides for sequencing applications. Yet, due to their small channel sizes, they preclude the passage of large macromolecules, e.g., therapeutics. Here, the unique combined properties of DNA origami nanotechnology, machine-inspired design, and synthetic biology are harnessed, to present a structurally reconfigurable DNA origami MechanoPore (MP) that features a lumen that is tuneable in size through molecular triggers. Controllable switching of MPs between 3 stable states is confirmed by 3D-DNA-PAINT super-resolution imaging and through dye-influx assays, after reconstitution of the large MPs in the membrane of liposomes via an inverted-emulsion cDICE technique. Confocal imaging of transmembrane transport shows size-selective behavior with adjustable thresholds. Importantly, the conformational changes are fully reversible, attesting to the robust mechanical switching that overcomes pressure from the surrounding lipid molecules. These MPs advance nanopore technology, offering functional nanostructures that can be tuned on-demand - thereby impacting fields as diverse as drug delivery, biomolecule sorting, and sensing, as well as bottom-up synthetic biology.
摘要：
生物纳米孔至关重要地控制着生物分子在细胞中脂质膜的进出口。他们在生物物理学和生物技术中得到了广泛的应用，它们通常狭窄的地方，固定的直径使离子和小分子的选择性运输，以及用于测序应用的DNA和肽。然而，由于它们的通道尺寸小，它们排除了大分子的通过，例如，治疗学。这里,DNA折纸纳米技术的独特组合特性，受机器启发的设计，利用合成生物学，提供结构上可重构的DNA折纸机械孔（MP），其特征是通过分子触发调节大小的管腔。通过3D-DNA-PAINT超分辨率成像和染料流入测定证实了MPs在3种稳定状态之间的可控切换。在通过反相乳液cDICE技术重构脂质体膜中的大MPs后。跨膜转运的共聚焦成像显示具有可调阈值的尺寸选择行为。重要的是,构象变化是完全可逆的，证明了强大的机械切换，克服了周围脂质分子的压力。这些议员推进纳米孔技术，提供可按需调整的功能性纳米结构-从而影响药物输送等领域，生物分子分选，和感应，以及自下而上的合成生物学。
