DNA origami has emerged as a highly programmable method to construct customized objects and functional devices in the 10–100 nm scale. Scaling up the size of the DNA origami would enable many potential applications, which include metamaterial construction and surface-based biophysical assays. Here we demonstrate that a six-helix bundle DNA origami nanostructure in the submicrometre scale (meta-DNA) could be used as a magnified analogue of single-stranded DNA, and that two meta-DNAs that contain complementary ‘meta-base pairs’ can form double helices with programmed handedness and helical pitches. By mimicking the molecular behaviours of DNA strands and their assembly strategies, we used meta-DNA building blocks to form diverse and complex structures on the micrometre scale. Using meta-DNA building blocks, we constructed a series of DNA architectures on a submicrometre-to-micrometre scale, which include meta-multi-arm junctions, three-dimensional (3D) polyhedrons, and various 2D/3D lattices. We also demonstrated a hierarchical strand-displacement reaction on meta-DNA to transfer the dynamic features of DNA into the meta-DNA. This meta-DNA self-assembly concept may transform the microscopic world of structural DNA nanotechnology.

DNA 折纸已成为一种高度可编程的方法，可用于构建 10-100 nm 尺度的定制对象和功能设备。扩大 DNA 折纸的大小将使许多潜在的应用成为可能，包括超材料构建和基于表面的生物物理分析。在这里，我们证明了亚微米级的六螺旋束 DNA 折纸纳米结构（元 DNA）可以用作单链 DNA 的放大类似物，并且两个包含互补“元碱基对”的元 DNA 可以形成具有程序化的手性和螺距的双螺旋。通过模仿 DNA 链的分子行为及其组装策略，我们使用元 DNA 构建块在微米尺度上形成多样化和复杂的结构。使用元 DNA 构建模块，我们构建了一系列亚微米到微米尺度的 DNA 架构，包括元多臂连接、三维 (3D) 多面体和各种 2D/3D 晶格。我们还展示了对元 DNA 的分层链置换反应，以将 DNA 的动态特征转移到元 DNA 中。这种元 DNA 自组装概念可能会改变结构 DNA 纳米技术的微观世界。