RNA聚合酶动态调控DNA转录的单分子水平研究进展

Advances in single-molecule investigation of dynamic DNA transcription regulation by RNA polymerase

真核生物的RNA聚合酶Ⅱ(Pol Ⅱ)和原核生物的RNA聚合酶(RNAP)主要负责转录合成信使RNA(mRNA),调控不同基因的转录水平,以调节生物体的生长发育和应对复杂多变的环境。研究者采用传统的荧光显微镜观测到RNAP可形成团簇,据此针对DNA转录调控提出“转录工厂”模型。随着单分子技术的发展,研究者在单分子水平上观测到了活细胞中RNAP动态调控DNA转录,提出RNAP可以通过液-液相分离机制进行转录调控。该综述总结了不同单分子荧光显微镜的技术原理,以及相关的荧光探针标记方法,并介绍了在真核生物和原核生物中应用单分子成像技术可视化RNA聚合酶动态调控DNA转录过程的研究进展,最后展望了单分子技术在转录调控研究中的应用前景。

Eukaryotic RNA polymerase II(Pol II) and prokaryotic RNA polymerase(RNAP) are mainly dedicated to messenger RNA(mRNA) synthesis, influencing the growth and development of organisms as well as in response to complicated environment conditions by regulating the transcriptional level of different genes. Clusters assembled by RNA polymerases were observed using conventional fluorescence microscopy, which was proposed as a “transcription factories” model for DNA transcription regulation.However, along with the development of single-molecule technology, dynamic regulation of transcription by RNAP was observed at single-molecule level, which thus raised the liquid-liquid phase separation model of RNAP transcription regulation. This paper reviewed the technical principles of multiple single-molecule fluorescent microscopies and the related labeling strategies via fluorescence probes. The advances in application of single-molecule technology in visualizing dynamic DNA transcription regulation of RNA polymerase were presented for both prokaryotes and eukaryotes. The application prospects of transcription regulation investigation using single-molecule technologies are introduced briefly at the end of this paper.