The cover image was inspired by my long-standing hobby of watercolor painting. When traveling, I often carry a small sketchbook and watercolor inks to capture buildings, streets, and landscapes. For the cover of the February 3 issue of Biophysical Journal, I used a watercolor painting app on an iPad, deliberately choosing a watercolor style to reflect the softness and warmth of artificial cells. Unlike sharp, schematic illustrations, watercolor allows soft materials to appear deformable and lifelike, emphasizing that artificial cells are physical objects made of flexible molecular assemblies. This choice aligns with the core message of our original research article that explores how cell-scale structures emerge from interactions among small molecular components.
The image illustrates a key step in constructing artificial cells: the formation of cell-sized liposomes by using the inverted emulsion method. In this process, a water-in-oil droplet passes through an oil–water interface under gravity or centrifugation and becomes enclosed by a lipid membrane. In the painting, the droplet’s descent represents this physically driven transformation, while the blurred interface highlights the continuous nature of membrane formation. This approach provides a versatile platform for building artificial cells that can host active biochemical and mechanical processes, enabling studies of cytoskeleton-driven cellular behaviors as well as applications in synthetic cell engineering, as demonstrated in an application example reported in our recent preprint .
More broadly, the image reflects our group’s interest in the physical principles of self-organization underlying cellular functions. Using the cytoskeleton as a model system, we study how ordered structures and dynamic behaviors arise from small molecular components through biochemical reactions and physical interactions. Although watercolor serves here as a visual metaphor, the focus of our research is on identifying the minimal physical rules that give rise to complex, cell-like functions. This perspective—bridging physics and synthetic biology—captures the core vision of our laboratory .
— Hibiki Sakata, Hitomi Matsubara, Kanako Gomi, and Makito Miyazaki