Adenosine triphosphate (ATP) is the canonical energy carrier that powers cellular machines, drives metabolic reactions, and serves as a precursor to nucleic acids. On page 753 of this issue, Patel et al. (1) propose a previously unknown function for ATP in maintaining protein solubility and preventing macromolecular aggregation. They show that at physiologic concentrations (2 to 8 mM), the physical properties of ATP alone enable it to dissolve liquid-liquid phase-separated droplets and amyloid fibers. These findings suggest an additional way for cells to use ATP to maintain proteostasis in the crowded cytoplasm and also fine-tune the material properties of nonmembrane-bound organelles and the cell interior in general.
