[3P-55] The molecular mechanism of Min system for protein wave formation and its phases in cell-sized space
Min system is a bacterial spatiotemporal regulation system for cell division. Three remarkable features of the Min system are i) a reaction-diffusion coupling of molecules (MinDE) shapes spatiotemporal organization (Min wave), ii) Conformational dynamics of MinE is a key to emerge the Min wave, and iii) Min wave appears at limited concentration ranges of MinDE. In this study, we report reconstitution of Min wave in cell-sized space by the finding that a protein crowding environment is required for the reconstitution due to large surface-area-to-volume ratio. By using the reconstituted system, we found suppression of spontaneous localization of MinE by protein crowder was the trigger for the emergence of Min wave in cell-sized space and revealed that the equilibrium of MinE conformational dynamics was a regulator of the limited concentration ranges of MinE for Min wave emergence. We also showed that spatiotemporal regulation of Min system was able to be controlled by a reconstituted transcription-translation system in artificial cells. The findings in this study shed light on the molecular mechanism of spatiotemporal regulation of proteins that emerged in cell-sized, and contribute to design principles for self-assembly molecules.