Cell-Size Confinement Drives Size-Dependent Scaling of Intracellular Reaction-Diffusion Waves for Robust Patterning.

Intracellular reaction-diffusion (iRD) waves are a mechanism to set the positions of molecules within cells for their proper biological function. Despite their biological importance, the physical characteristics of iRD waves were still elusive due to the specific constraints of cells, where spatial confinement and surface-bulk coupling govern pattern formation. Here, by an artificial cell experiment of iRD wave for cell division (Min wave) using defined factors, we showed that the wavelength of iRD wave is selected by the space size. This wavelength selection adjusted the wave shape and speed to fit the spatial sizes. Furthermore, this mechanism conferred the robustness of the macroscopic pattern of iRD waves under physicochemical perturbations. Theoretical analysis confirmed that this can be explained by the theoretical Min wave model and suggests its generality among iRD waves. These findings indicate the reason why cells use RD waves to place molecules with versatile functions.