Proteins perform a staggering variety of functions in the cell. Traditionally, protein function was thought to be hard-wired into the folded structure and conformational dynamics of each protein molecule. Recent work describes a new mode of protein functionality driven by the collective behavior of many different proteins; most of which lack a defined structure. These proteins form clusters or granules in which unstructured polypeptides interact transiently. Nonspecific multivalent interactions drive the formation of phase-separated structures resembling aggregates. This type of functional aggregate granule can be thought of as a single supermolecular functional entity that derives function from its unique material properties. In this review we examine the emerging idea of protein granules as a new functional and structural unit of cellular organization.

蛋白质在细胞中执行多种功能。传统上，蛋白质功能被认为是硬连接到每个蛋白质分子的折叠结构和构象动力学中。最近的工作描述了一种由许多不同蛋白质的集体行为驱动的蛋白质功能性新模式。其中大多数缺乏明确的结构。这些蛋白质形成簇或颗粒，其中未结构化的多肽会短暂相互作用。非特异性多价相互作用驱动形成类似于聚集体的相分离结构的形成。可以将这种功能性聚集颗粒视为单个超分子功能实体，该功能实体从其独特的材料特性中获取功能。