6R6G

Structure of XBP1u-paused ribosome nascent chain complex with SRP.

これはPDB形式変換不可エントリーです。

6R6G の概要

• エントリーDOI: 10.2210/pdb6r6g/pdb
• 関連するPDBエントリー: 6R5Q
• EMDBエントリー: 4729 4735
• 分子名称: eS31, uS14, uL2, ... (94 entities in total)
• 機能のキーワード: translational pausing, xbp1, upr, cotranslational targeting, srp., ribosome
• 由来する生物種: Homo sapiens (Human); 詳細
• タンパク質・核酸の鎖数: 92
• 化学式量合計: 3366388.66

構造登録者

Shanmuganathan, V.,Cheng, J.,Braunger, K.,Berninghausen, O.,Beatrix, B.,Beckmann, R. (登録日: 2019-03-27, 公開日: 2019-07-10, 最終更新日: 2019-10-30)

主引用文献

Shanmuganathan, V.,Schiller, N.,Magoulopoulou, A.,Cheng, J.,Braunger, K.,Cymer, F.,Berninghausen, O.,Beatrix, B.,Kohno, K.,Heijne, G.V.,Beckmann, R.
Structural and mutational analysis of the ribosome-arresting human XBP1u.
Elife, 8:-, 2019

PubMed Abstract: XBP1u, a central component of the unfolded protein response (UPR), is a mammalian protein containing a functionally critical translational arrest peptide (AP). Here, we present a 3 Å cryo-EM structure of the stalled human XBP1u AP. It forms a unique turn in the ribosomal exit tunnel proximal to the peptidyl transferase center where it causes a subtle distortion, thereby explaining the temporary translational arrest induced by XBP1u. During ribosomal pausing the hydrophobic region 2 (HR2) of XBP1u is recognized by SRP, but fails to efficiently gate the Sec61 translocon. An exhaustive mutagenesis scan of the XBP1u AP revealed that only 8 out of 20 mutagenized positions are optimal; in the remaining 12 positions, we identify 55 different mutations increase the level of translational arrest. Thus, the wildtype XBP1u AP induces only an intermediate level of translational arrest, allowing efficient targeting by SRP without activating the Sec61 channel.

PubMed: 31246176
DOI: 10.7554/eLife.46267

実験手法

ELECTRON MICROSCOPY (3.7 Å)