Liquid-liquid phase separation in human diseases: Functions, mechanisms and treatments

Cells are separated into functional regions by non-membrane organelles and membrane-enclosed organelles, ensuring that various cellular activities occur in a controlled manner in space and time. There is increasing evidence that large numbers of non-membrane compartments, collectively referred to as biomacromolecular condensates or droplets, are formed in cells through liquid-liquid phase separation (LLPS). Phase-separated condensates play a role in numerous biological activities and intracellular spatiotemporal regulation, such as cellular transcription, chromatin maintenance, signal transduction, and immune response. However, abnormal phase separation and transformation are closely linked to many major human diseases. This review comprehensively summarizes the detailed mechanisms of biomacromolecular condensates formation and physiological functions, and discusses the latest progress in elucidating the pathological mechanisms of various human diseases caused by abnormal LLPS and their treatment options.