9PRO

Human 19S proteasome bound to TXNL1 PITH domain and PSMD5

これはPDB形式変換不可エントリーです。

9PRO の概要

• エントリーDOI: 10.2210/pdb9pro/pdb
• 関連するPDBエントリー: 9PMJ
• EMDBエントリー: 71810
• 分子名称: RPT1, RPN6, RPN7, ... (24 entities in total)
• 機能のキーワード: proteasome, 19s, rp, txnl1, psmd5, hydrolase
• 由来する生物種: Homo sapiens (human); 詳細
• タンパク質・核酸の鎖数: 20
• 化学式量合計: 992561.68

構造登録者

Chen, X.,Negi, H.,Walters, K.J. (登録日: 2025-07-24, 公開日: 2026-07-01, 最終更新日: 2026-08-19)

主引用文献

Lee, K.,Negi, H.,Chen, X.,Atallah-Yunes, K.,Truslow, S.,Castelino, R.E.,Guest, M.R.,Ciancone, A.M.,Lu, X.,Tarasov, S.G.,Chari, R.,Walters, K.J.,O'Reilly, F.J.
Structures of dynamic interactors at native proteasomes by PhIX-MS and cryo-electron microscopy.
Mol.Cell, 86:3067-, 2026

PubMed Abstract: Molecular machines rely on dynamic, low-affinity interactions to perform their functional roles. We developed PhIX-MS (photo-induced in situ crosslinking-mass spectrometry), a structural proteomics workflow to capture topological information for such transient interactions in cells by UV-activated crosslinking. Applying PhIX-MS with cryo-electron microscopy (cryo-EM) to proteasomes, we mapped the redox sensor TXNL1 at the proteasome regulatory particle (RP), including its dynamic thioredoxin-like domain near RPN2/PSMD1 and RPN13/ADRM1, where it is ideal for reducing substrates prior to proteolysis. RPs without the proteolytic core particle (CP) were structurally resolved while bound to TXNL1 and/or the chaperone PSMD5/S5b, which inserts its C terminus into the ATPase pore, causing extensive structural rearrangements. Additionally, PhIX-MS and AlphaFold identified the ubiquitin ligase UBE3C/Hul5 at RPN2, RPN3, and a dynamic RPN10 region, tethering UBE3C above the substrate entry channel. Our integrative approach enables the localization of native, low-affinity protein interactions and is broadly applicable to dynamic macromolecular assemblies.

PubMed: 42476128
DOI: 10.1016/j.molcel.2026.06.032

実験手法

ELECTRON MICROSCOPY (4.07 Å)