Structures and Compositional Dynamics of Mediator in Transcription Regulation

Overview

Journal Curr Opin Struct Biol

Date 2024 Jul 27

PMID 39067114

Authors

Tao Li

Ti-Chun Chao

Kuang-Lei Tsai

Affiliations

Soon will be listed here.

Abstract

The eukaryotic Mediator, comprising a large Core (cMED) and a dissociable CDK8 kinase module (CKM), functions as a critical coregulator during RNA polymerase II (RNAPII) transcription. cMED recruits RNAPII and facilitates the assembly of the pre-initiation complex (PIC) at promoters. In contrast, CKM prevents RNAPII binding to cMED while simultaneously exerting positive or negative influence on gene transcription through its kinase function. Recent structural studies on cMED and CKM have revealed their intricate architectures and subunit interactions. Here, we explore these structures, providing a comprehensive insight into Mediator (cMED-CKM) architecture and its potential mechanism in regulating RNAPII transcription. Additionally, we discuss the remaining puzzles that require further investigation to fully understand how cMED coordinates with CKM to regulate transcription in various events.

Citing Articles

Structural basis of the human transcriptional Mediator regulated by its dissociable kinase module.

Chao T, Chen S, Kim H, Tang H, Tseng H, Xu A Mol Cell. 2024; 84(20):3932-3949.e10.

PMID: 39321804 PMC: 11832219. DOI: 10.1016/j.molcel.2024.09.001.

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