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Repurposing the RNA‐guided endonuclease Cas9 to develop artificial CRISPR molecular machines represents a new direction toward synthetic molecular information processing. The operation of CRISPR‐Cas9‐based machines, nevertheless, relies on the molecular recognition of freely diffused sgRNA/Cas9, making it practically challenging to perform spatially regulated localized searching or navigation. Here, we develop a DNA origami‐based single‐molecule CRISPR machine that can perform spatially resolved DNA cleavage via either free or localized searching modes. When triggered at a specific site on the DNA origami with nanoscale accuracy, the free searching mode leads to searching activity that gradually decays with the distance, whereas the localized mode generates spatially‐confined searching activity. Our work expands the function of CRISPR molecular machines and lays foundations to develop integrated molecular circuits and high‐throughput nucleic acid detection. [ABSTRACT FROM AUTHOR]

Membrane curvature reflects physical forces operating on the lipid membrane, which plays important roles in cellular processes. Here, we design a mechanosensitive DNA (MSD) nanomachine that mimics natural mechanosensitive PIEZO channels to convert the membrane tension changes of lipid vesicles with different sizes into fluorescence signals in real time. The MSD nanomachine consists of an archetypical six‐helix‐bundle DNA nanopore, cholesterol‐based membrane anchors, and a solvatochromic fluorophore, spiropyran (SP). We find that the DNA nanopore effectively amplifies subtle variations of the membrane tension, which effectively induces the isomerization of weakly emissive SP into highly emissive merocyanine isomers for visualizing membrane tension changes. By measuring the membrane tension via the fluorescence of MSD nanomachine, we establish the correlation between the membrane tension and the curvature that follows the Young‐Laplace equation. This DNA nanotechnology‐enabled strategy opens new routes to studying membrane mechanics in physiological and pathological settings. [ABSTRACT FROM AUTHOR]

Integrating dissimilar materials at the nanoscale is crucial for modern electronics and optoelectronics. The structural DNA nanotechnology provides a universal platform for precision assembly of materials; nevertheless, heterogeneous integration of dissimilar materials with DNA nanostructures has yet to be explored. We report a DNA origami‐encoded strategy for integrating silica‐metal heterostructures. Theoretical and experimental studies reveal distinctive mechanisms for the binding and aggregation of silica and metal clusters on protruding double‐stranded DNA (dsDNA) strands that are prescribed on the DNA origami template. In particular, the binding energy differences of silica/metal clusters and DNA molecules underlies the accessibilities of dissimilar material areas on DNA origami. By programming the densities and lengths of protruding dsDNA strands on DNA origami, silica and metal materials can be independently deposited at their predefined areas with a high vertical precision of 2 nm. We demonstrate the integration of silica‐gold and silica‐silver heterostructures with high site addressability. This DNA nanotechnology‐based strategy is thus applicable for integrating various types of dissimilar materials, which opens up new routes to bottom‐up electronics. [ABSTRACT FROM AUTHOR]