Department of Biology, McGill University, Montreal, QC, Canada.
EcoSal Plus. 2021 Dec 15;9(2):eESP00112020. doi: 10.1128/ecosalplus.ESP-0011-2020. Epub 2021 Jun 1.
Proteins are major contributors to the composition and the functions in the cell. They often assemble into larger structures, macromolecular machines, to carry out intricate essential functions. Although huge progress in understanding how macromolecular machines function has been made by reconstituting them , the role of the intracellular environment is still emerging. The development of fluorescence microscopy techniques in the last 2 decades has allowed us to obtain an increased understanding of proteins and macromolecular machines in cells. Here, we describe how proteins move by diffusion, how they search for their targets, and how they are affected by the intracellular environment. We also describe how proteins assemble into macromolecular machines and provide examples of how frequent subunit turnover is used for them to function and to respond to changes in the intracellular conditions. This review emphasizes the constant movement of molecules in cells, the stochastic nature of reactions, and the dynamic nature of macromolecular machines.
蛋白质是细胞组成和功能的主要贡献者。它们经常组装成更大的结构，即大分子机器，以执行复杂的基本功能。尽管通过重组这些大分子机器在理解它们的功能方面取得了巨大进展，但细胞内环境的作用仍在不断显现。在过去的 20 年中，荧光显微镜技术的发展使我们能够更深入地了解细胞中的蛋白质和大分子机器。在这里，我们描述了蛋白质如何通过扩散移动，它们如何寻找目标，以及它们如何受到细胞内环境的影响。我们还描述了蛋白质如何组装成大分子机器，并提供了一些例子，说明频繁的亚基替换如何使它们发挥功能并对细胞内环境的变化做出响应。这篇综述强调了分子在细胞中的持续运动、反应的随机性和大分子机器的动态性质。
