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Biology subjects

Huang, C. M.

Publications and source records attributed to Huang, C. M..

3 recordsLinked to original sources

Versatile Computer Aided Design of Freeform DNA Nanostructures and Assemblies

Recent advances in structural DNA nanotechnology have been facilitated by design tools that continue to push the limits of structural complexity while simplifying an often-tedious design process. We recently introduced the software MagicDNA, which enables design of complex 3D DNA assemblies with many components; however, the design of structures with freeform features like vertices or curvature still required iterative design guided by simulation feedback and user intuition. Here, we present an updated design tool, MagicDNA 2.0, that automates the design of freeform 3D geometries, leveraging design models informed by coarse-grained molecular dynamics simulations. Our GUI-based, stepwise design approach integrates a high level of automation with versatile control over assembly and sub-component design parameters. We experimentally validated this approach by fabricating a range of DNA origami assemblies with complex freeform geometries, including a 3D Nozzle, G-clef, and Hilbert and Trifolium curves, confirming excellent agreement between design input, simulation, and structure formation.

bioengineering↗

Steric Communication between Dynamic Components on DNA nanodevices

Biomolecular nanotechnology has helped emulate basic robotic capabilities such as defined motion, sensing, and actuation in synthetic nanoscale systems. DNA origami is an attractive approach for nanorobotics, as it enables creation of devices with complex geometry, programmed motion, rapid actuation, force application, and various kinds of sensing modalities. Advanced robotic functions like feedback control, autonomy, or programmed routines also require the ability to transmit signals among sub-components. Prior work in DNA nanotechnology has established approaches for signal transmission, for example through diffusing strands or structurally coupled motions. However, soluble communication is often slow and structural coupling of motions can limit the function of individual components, for example to respond to the environment. Here, we introduce a novel approach inspired by protein allostery to transmit signals between two distal dynamic components through steric interactions. These components undergo separate thermal fluctuations where certain conformations of one arm will sterically occlude conformations of the distal arm. We implement this approach in a DNA origami device consisting of two stiff arms each connected to a base platform via a flexible hinge joint. We demonstrate the ability for one arm to sterically regulate both the range of motion as well as the conformational state (latched or freely fluctuating) of the distal arm, results that are quantitatively captured by mesoscopic simulations using experimentally informed energy landscapes for hinge-angle fluctuations. We further demonstrate the ability to modulate signal transmission by mechanically tuning the range of thermal fluctuations and controlling the conformational states of the arms. Our results establish a communication mechanism well-suited to transmit signals between thermally fluctuating dynamic components and provide a path to transmitting signals where the input is a dynamic response to parameters like force or solution conditions.

bioengineering↗

Integrating computer-aided engineering and computer-aided design for DNA assemblies

Functional properties of modern engineering products result from merging the geometry and material properties of underlying components into sophisticated overall assemblies. The foundation of this design process is an integration of computer aided design (CAD) tools that allow rapid geometric modifications with robust simulation tools to guide design iterations (i.e. computer-aided engineering, CAE). Recently, DNA has been used to make nanodevices for a myriad of applications across fields including medicine, nanomanufacturing, synthetic biology, biosensing, and biophysics. However, currently these self-assembled DNA nanodevices rely primarily on geometric design, and hence, they have not demonstrated the same sophistication as real-life products. We present an iterative design pipeline for DNA assemblies that integrates CAE based on coarse-grained molecular dynamics with a versatile CAD approach that combines top-down automation with bottom-up control over geometry. This intuitive framework redefines the scope of structural complexity and enhances mechanical and dynamic design of DNA assemblies.

bioengineering↗