Chemotactic cell motility plays a critical role in many biological functions, such as immune response and embryogenesis. Constructing synthetic cell-mimicking systems, such as a dynamic protocell, likewise requires molecular mechanisms that respond to environmental stimuli and execute programmed motility behaviors. Although various molecular components were proposed to achieve diverse functions in synthetic protocells, chemotactic motility on surfaces has not been reported thus far. Here we show directional motility in synthetic lipid vesicles capable of chasing each other by programming DNA components. We demonstrate that the "follow" vesicle recognizes and migrates along the moving trajectory of the "lead" vesicle with an enhanced speed, thus mimicking natural chemotaxis in cell migration. This work provides new possibilities for building synthetic protocells with complex functions such as programmed morphogenesis and cooperative motion. With the vast library of dynamic DNA components, we envision that this platform will enable new discoveries in fundamental sciences and novel applications in biotechnology.
Keywords: DNA nanotechnology; DNA walker; Synthetic vesicles; chemokinesis; chemotaxis; protocells.