Intracellular Organelles Driven by Liquid-Liquid Phase Separation

Recently, there is growing evidence in the field of cell biology that membrane-less organelles or condensates are formed by liquid-liquid phase separation (LLPS), as well as some types of membrane-bound organelles like lipid rafts and lipid droplets. Biophysical analyses are powerful and indispensable to elucidate those structures, dynamics and (dys)functions. Here, we combine in vivo intracellular imaging with in vitro synthetic biology and soft-matter physics, to show a new avenue for understanding the biophysics of LLPS-driven organelles. In this review, we particularly discuss macro-to-micro phase separation in lipid rafts and liquid-liquid crystal phase transition in lipid droplets.