Institute for Systems Genetics, Science Building 807, 435 E 30th Street, NYC, NY 10016, USA.
Johns Hopkins University, Department of Biology, 3400 N Charles St, Baltimore, MD 21218, USA.
Curr Opin Genet Dev. 2021 Apr;67:94-102. doi: 10.1016/j.gde.2020.12.001. Epub 2021 Jan 7.
A universe of transcription factors (TFs), cofactors, as well as chromatin remodeling and modifying enzymes combine or compete on chromatin to control transcription. Measuring quantitatively how these proteins dynamically interact is required in order to formulate models with predictive ability to elucidate transcription control mechanisms. Single molecule tracking (SMT) provides a powerful tool towards this goal: it is a fluorescence microscopy approach that measures the location and mobility of individual TF molecules, as well as their rates of association with and dissociation from chromatin in the physiological context of the living cell. Here we review SMT principles, and discuss key TF properties uncovered by live-cell SMT, such as fast turnover (seconds), and formation of clusters that locally increase activity.
转录因子 (TFs)、辅助因子以及染色质重塑和修饰酶的宇宙在染色质上结合或竞争，以控制转录。为了制定具有预测能力的模型来阐明转录控制机制，需要定量测量这些蛋白质如何动态相互作用。单分子跟踪 (SMT) 为此提供了一个强大的工具：它是一种荧光显微镜方法，可测量单个 TF 分子的位置和迁移率，以及它们在活细胞的生理环境中与染色质结合和解离的速率。在这里，我们回顾了 SMT 的原理，并讨论了活细胞 SMT 揭示的关键 TF 特性，例如快速周转（秒）和形成局部增加活性的簇。
