Felix J. Rizzuto

Hierarchical DNA nanostructures offer programmable functions at scale, but making these structures dynamic, while keeping individual components intact, is challenging. Here we show that the DNA A‐motif—protonated, self‐complementary poly(adenine) sequences—can propagate DNA origami into one‐dimensional, micron‐length fibrils. When coupled to a small molecule pH regulator, visible light can activate the hierarchical assembly of our DNA origami into dissipative fibrils. This system is recyclable and does not require DNA modification. By employing a modular and waste‐free strategy to assemble and disassemble hierarchical structures built from DNA origami, we offer a facile and accessible route to developing well‐defined, dynamic, and large DNA assemblies with temporal control. As a general tool, we envision that coupling the A‐motif to cycles of dissipative protonation will allow the transient construction of diverse DNA nanostructures, finding broad applications in dynamic and non‐equilibrium nanotechnology.