Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA.
Methods. 2019 Apr 15;159-160:90-95. doi: 10.1016/j.ymeth.2019.01.016. Epub 2019 Jan 29.
During transcription along nucleosomal DNA, RNA polymerase II (Pol II) pauses at multiple positions and induces formation of multiple intermediates that aid in maintaining proper chromatin structure. To describe the kinetics of this multiple-step reaction, we utilized a computational model-based approach and KinTek Explorer software to analyze the time courses. Here we describe the stepwise protocol for analysis of the kinetics of transcription through a nucleosome that provides the rate constants for each step of this complex process. We also present an example where this time-resolved approach was applied to study the mechanism of histone chaperone FACT action during Pol II transcription through a single nucleosome by comparing the rate constants derived in the presence or in the absence of FACT.
在核小体 DNA 上进行转录时,RNA 聚合酶 II(Pol II)会在多个位置暂停,并诱导形成多种中间体,从而有助于维持适当的染色质结构。为了描述这一多步反应的动力学,我们利用基于计算模型的方法和 KinTek Explorer 软件来分析时间过程。在这里,我们描述了分析穿过核小体的转录动力学的逐步方案,该方案提供了该复杂过程每个步骤的速率常数。我们还提供了一个示例,其中通过比较有或没有 FACT 时得出的速率常数,应用这种时分辨方法来研究组蛋白伴侣 FACT 在 Pol II 穿过单个核小体转录过程中的作用机制。