Small organic osmolytes accelerate actin filament assembly and stiffen filaments

Actin filament assembly and mechanics are crucial for maintenance of cell structure, motility, and division. Actin filament assembly occurs in a crowded intracellular environment consisting of various types of molecules, including small organic molecules known as osmolytes. Ample evidence highlights the protective functions of osmolytes, including their effects on protein stability and their ability to counteract cellular osmotic stress. Recently, one such osmolyte, trimethylamine-N-oxide (TMAO), has been shown to modulate actin filament assembly based on bulk fluorescence assays.