In the last decade, liquid-liquid phase separation has emerged as a fundamental principle in the organization of crowded cellular environments into functionally distinct membraneless compartments. It is now established that biomolecules can condense into various physical phases, traditionally defined for simple polymer systems, and more recently elucidated by techniques employed in life sciences. We review pioneering cryo-electron tomography studies that have begun to unravel a wide spectrum of molecular architectures, ranging from amorphous to crystalline assemblies, that underlie cellular condensates. These observations bring into question current interpretations of microscopic phase behavior. Furthermore, by examining emerging concepts of non-classical phase separation pathways in small-molecule crystallization, we draw parallels with biomolecular condensation that highlight aspects not yet fully explored. In particular, transient and metastable intermediates that might be challenging to capture experimentally inside cells could be probed through computational simulations and enable a multi-scale understanding of the subcellular organization governed by distinct phases.

在过去的十年中，液-液相分离已成为将拥挤的细胞环境组织成​​功能独特的无膜隔室的基本原理。现已确定，生物分子可以凝结成各种物理相，传统上是为简单的聚合物系统定义的，而最近由生命科学中采用的技术加以阐明。我们回顾了开创性的低温电子层析成像研究，这些研究已经开始揭示构成分子凝结物基础的从无定形到结晶组装的各种分子结构。这些发现使人们对微观相行为的当前解释产生疑问。此外，通过研究小分子结晶中非经典相分离途径的新兴概念，我们将生物分子缩合与之相提并论，以突出尚未充分探索的方面。特别是，可以通过计算模拟来探究可能难以通过实验捕获到细胞内部的瞬态和亚稳态中间体，并能够对由不同阶段控制的亚细胞组织进行多尺度理解。