resume
Phase separation is a popular idea to explain how cells organize their contents, but recently researchers have raised doubts about how often it occurs in cells and how important it is for them. Phase separation occurs when proteins or other molecules condense into liquid droplets that resemble oil globules that form in salad dressing. Some scientists have proposed that the process is common in cells and produces and maintains organelles without a membrane, such as nucleolus, Cajal bodies and stress granules. Evidence also suggests that faulty phase separation promotes diseases such as cancer and some neurological diseases. But a recent review challenged the field by relying on qualitative rather than quantitative evidence, over-interpreting image studies, relying on equivocal techniques to demonstrate phase separation and other flaws.