3RPG

Bmi1/Ring1b-UbcH5c complex structure

3RPG の概要

• エントリーDOI: 10.2210/pdb3rpg/pdb
• 関連するPDBエントリー: 1X23 2CKL 2FUH 2H0D
• 分子名称: Ubiquitin-conjugating enzyme E2 D3, Polycomb complex protein BMI-1, E3 ubiquitin-protein ligase RING2, ... (5 entities in total)
• 機能のキーワード: ubiquitin ligase, ligase
• 由来する生物種: Homo sapiens (human); 詳細
• 細胞内の位置: Cell membrane; Peripheral membrane protein: P61077; Nucleus: P35226 Q99496
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 44262.56

構造登録者

Bentley, M.L.,Dong, K.C.,Cochran, A.G. (登録日: 2011-04-26, 公開日: 2011-08-17, 最終更新日: 2023-09-13)

主引用文献

Bentley, M.L.,Corn, J.E.,Dong, K.C.,Phung, Q.,Cheung, T.K.,Cochran, A.G.
Recognition of UbcH5c and the nucleosome by the Bmi1/Ring1b ubiquitin ligase complex.
Embo J., 30:3285-3297, 2011

PubMed Abstract: The Polycomb repressive complex 1 (PRC1) mediates gene silencing, in part by monoubiquitination of histone H2A on lysine 119 (uH2A). Bmi1 and Ring1b are critical components of PRC1 that heterodimerize via their N-terminal RING domains to form an active E3 ubiquitin ligase. We have determined the crystal structure of a complex between the Bmi1/Ring1b RING-RING heterodimer and the E2 enzyme UbcH5c and find that UbcH5c interacts with Ring1b only, in a manner fairly typical of E2-E3 interactions. However, we further show that the Bmi1/Ring1b RING domains bind directly to duplex DNA through a basic surface patch unique to the Bmi1/Ring1b RING-RING dimer. Mutation of residues on this interaction surface leads to a loss of H2A ubiquitination activity. Computational modelling of the interface between Bmi1/Ring1b-UbcH5c and the nucleosome suggests that Bmi1/Ring1b interacts with both nucleosomal DNA and an acidic patch on histone H4 to achieve specific monoubiquitination of H2A. Our results point to a novel mechanism of substrate recognition, and control of product formation, by Bmi1/Ring1b.

PubMed: 21772249
DOI: 10.1038/emboj.2011.243

実験手法

X-RAY DIFFRACTION (2.6485 Å)