Cellular Olympics: Ultrafast Cellular Motility Across the Tree of Life.

Surprisingly, many single-celled organisms and specialized cell types can achieve speed and acceleration significantly faster than those of multicellular animals. These remarkable cellular machines must integrate energy storage and amplification in actuation, latches for triggered release, and energy dissipation without failure-all implemented in macromolecular assemblies inside a single cell. In this review, we first map the atlas of single cells across the tree of life that use ultrafast motility. We then quantitatively compare extreme acceleration, speed, area strain rate, volume expansion strain rate, and density change rate among single cells. Next, we generalize these ideas by placing various trigger, actuation, and dissipation mechanisms within a unified framework. We conclude with a detailed summary of the diverse functions enabled by ultrafast cellular motility, providing a comprehensive foundation for understanding extreme biophysics and its diverse role at the cellular scale.