7ENJ

Human Mediator (deletion of MED1-IDR) in a Tail-bent conformation (MED-B)

7ENJ の概要

• エントリーDOI: 10.2210/pdb7enj/pdb
• EMDBエントリー: 31191 31211
• 分子名称: Mediator of RNA polymerase II transcription subunit 1, Mediator of RNA polymerase II transcription subunit 14, Mediator of RNA polymerase II transcription subunit 15, ... (27 entities in total)
• 機能のキーワード: mediator complex, transcription
• 由来する生物種: Homo sapiens (Human); 詳細
• タンパク質・核酸の鎖数: 26
• 化学式量合計: 1303856.77

構造登録者

Yin, X.,Li, J.,Wu, Z.,Liu, W.,Xu, Y. (登録日: 2021-04-17, 公開日: 2021-05-19, 最終更新日: 2024-06-05)

主引用文献

Chen, X.,Yin, X.,Li, J.,Wu, Z.,Qi, Y.,Wang, X.,Liu, W.,Xu, Y.
Structures of the human Mediator and Mediator-bound preinitiation complex.
Science, 372:-, 2021

PubMed Abstract: The 1.3-megadalton transcription factor IID (TFIID) is required for preinitiation complex (PIC) assembly and RNA polymerase II (Pol II)-mediated transcription initiation on almost all genes. The 26-subunit Mediator stimulates transcription and cyclin-dependent kinase 7 (CDK7)-mediated phosphorylation of the Pol II C-terminal domain (CTD). We determined the structures of human Mediator in the Tail module-extended (at near-atomic resolution) and Tail-bent conformations and structures of TFIID-based PIC-Mediator (76 polypeptides, ~4.1 megadaltons) in four distinct conformations. PIC-Mediator assembly induces concerted reorganization (Head-tilting and Middle-down) of Mediator and creates a Head-Middle sandwich, which stabilizes two CTD segments and brings CTD to CDK7 for phosphorylation; this suggests a CTD-gating mechanism favorable for phosphorylation. The TFIID-based PIC architecture modulates Mediator organization and TFIIH stabilization, underscoring the importance of TFIID in orchestrating PIC-Mediator assembly.

PubMed: 33958484
DOI: 10.1126/science.abg0635

実験手法

ELECTRON MICROSCOPY (4.4 Å)