近日，美国普林斯顿大学Clifford P. Brangwynne和Ned S. Wingreen及其团队的研究发现细胞内凝聚物的尺寸分布反映了聚结和成核之间的竞争。2023年2月2日，国际知名学术期刊《自然—物理学》发表了这一成果。

研究人员展示了天然和合成凝聚体都显示出指数大小分布，这是通过蒙特卡罗模拟快速成核后合并捕获的。相反，病态聚集物呈现幂律尺寸分布。这些不同的行为反映了成核和聚结动力学的相对重要性。课题组人员通过利用合成和天然凝聚体组合，探索了决定凝聚体大小的潜在物理机制。突然形核的指数分布和连续形核的幂律分布的出现可能反映了决定凝聚体尺寸分布的一般原理。

据了解，生物分子凝聚体相分离已成为细胞内组织的一种机制，并影响许多细胞内过程，包括通过酶和路径中间体的聚集反应途径。精确和快速的时空控制需要调整凝聚体尺寸大小。然而，调控凝聚体尺寸分布的物理过程仍然不清楚。

附：英文原文

Title: Size distributions of intracellular condensates reflect competition between coalescence and nucleation

Author: Lee, Daniel S. W., Choi, Chang-Hyun, Sanders, David W., Beckers, Lien, Riback, Joshua A., Brangwynne, Clifford P., Wingreen, Ned S.

Issue&Volume: 2023-02-02

Abstract: Phase separation of biomolecules into condensates has emerged as a mechanism for intracellular organization and affects many intracellular processes, including reaction pathways through the clustering of enzymes and pathway intermediates. Precise and rapid spatiotemporal control of reactions by condensates requires tuning of their sizes. However, the physical processes that govern the distribution of condensate sizes remain unclear. Here we show that both native and synthetic condensates display an exponential size distribution, which is captured by Monte Carlo simulations of fast nucleation followed by coalescence. In contrast, pathological aggregates exhibit a power-law size distribution. These distinct behaviours reflect the relative importance of nucleation and coalescence kinetics. We demonstrate this by utilizing a combination of synthetic and native condensates to probe the underlying physical mechanisms determining condensate size. The appearance of exponential distributions for abrupt nucleation versus power-law distributions under continuous nucleation may reflect a general principle that determines condensate size distributions.

DOI: 10.1038/s41567-022-01917-0

Source: https://www.nature.com/articles/s41567-022-01917-0