7TJ2

SARS-CoV-2 endoribonuclease Nsp15 bound to dsRNA

7TJ2 の概要

• エントリーDOI: 10.2210/pdb7tj2/pdb
• EMDBエントリー: 25915
• 分子名称: Uridylate-specific endoribonuclease nsp15, RNA (31-MER) (3 entities in total)
• 機能のキーワード: endoribonuclease, viral protein, viral protein-rna complex, viral protein/rna
• 由来する生物種: Severe acute respiratory syndrome coronavirus 2; 詳細
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 268789.89

構造登録者

Frazier, M.N.,Krahn, J.M.,Butay, K.J.,Dillard, L.B.,Borgnia, M.J.,Stanley, R.E. (登録日: 2022-01-14, 公開日: 2022-03-23, 最終更新日: 2024-06-05)

主引用文献

Frazier, M.N.,Wilson, I.M.,Krahn, J.M.,Butay, K.J.,Dillard, L.B.,Borgnia, M.J.,Stanley, R.E.
Flipped over U: structural basis for dsRNA cleavage by the SARS-CoV-2 endoribonuclease.
Nucleic Acids Res., 50:8290-8301, 2022

PubMed Abstract: Coronaviruses generate double-stranded (ds) RNA intermediates during viral replication that can activate host immune sensors. To evade activation of the host pattern recognition receptor MDA5, coronaviruses employ Nsp15, which is a uridine-specific endoribonuclease. Nsp15 is proposed to associate with the coronavirus replication-transcription complex within double-membrane vesicles to cleave these dsRNA intermediates. How Nsp15 recognizes and processes dsRNA is poorly understood because previous structural studies of Nsp15 have been limited to small single-stranded (ss) RNA substrates. Here we present cryo-EM structures of SARS-CoV-2 Nsp15 bound to a 52nt dsRNA. We observed that the Nsp15 hexamer forms a platform for engaging dsRNA across multiple protomers. The structures, along with site-directed mutagenesis and RNA cleavage assays revealed critical insight into dsRNA recognition and processing. To process dsRNA Nsp15 utilizes a base-flipping mechanism to properly orient the uridine within the active site for cleavage. Our findings show that Nsp15 is a distinctive endoribonuclease that can cleave both ss- and dsRNA effectively.

PubMed: 35801916
DOI: 10.1093/nar/gkac589

実験手法

ELECTRON MICROSCOPY (3.2 Å)