中介体复合物结构与转录调控机制

doi:10.3969/j.issn.0253-9608.2021.05.005

摘要/Abstract

摘要： 在真核生物中，中介体复合物 (Mediator complex) 接收转录激活子/基因特异型转录因子携带的转录激活信号，并将之传递给核心转录机器——RNA聚合酶II，在这个过程中起到桥梁的作用。中介体复合物与RNA聚合酶II、各种通用转录因子组装成转录前起始复合物，对于真核生物几乎所有基因的转录都是必需的。中介体复合物成分复杂多变，结构柔性较强，针对它的结构生物学和转录调控机制的研究已超过30年。文章小结了中介体复合物的发现历程、功能和组成以及结构生物学方面的突出成果，并对它可能的转录调控机制进行了初步阐释。

关键词: 中介体复合物, 转录前起始复合物, 真核转录, 结构生物学

Abstract: n eukaryotes, the Mediator complex receives transcriptional activation signals carried by transcriptional activators/gene-specific transcription factors and transmits them to the core transcriptional machinery, RNA polymerase II, acting as a bridge in this process. The Mediator complex interacts with RNA polymerase II and various general transcription factors to form the pre-initiation
complex, which is required for the transcription of almost all genes in eukaryotes. The subunit composition of the Mediator complex is complex and varied, and its conformation is flexible. The structural biology and transcriptional regulation mechanism of the Mediator complex have been studied for more than 30 years. In this review, the discovery, function, subunit composition and structural biology of the Mediator complex are summarized, and their possible transcriptional regulatory mechanisms are briefly discussed.

张贺桥, 聂焱. 中介体复合物结构与转录调控机制[J]. 自然杂志, 2021, 43(5): 349-358.

ZHANG Heqiao, NIE Yan. Structure and transcriptional regulation mechanism of Mediator complex[J]. Chinese Journal of Nature, 2021, 43(5): 349-358.

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