6C66

CRISPR RNA-guided surveillance complex, pre-nicking

6C66 の概要

• エントリーDOI: 10.2210/pdb6c66/pdb
• 関連するPDBエントリー: 6C66
• EMDBエントリー: 7346 7347
• 分子名称: CRISPR-associated helicase, Cas3 family, FE (III) ION, CRISPR-associated protein, Cse1 family, ... (10 entities in total)
• 機能のキーワード: crispr-cas, cascade, cas3, dna binding protein, dna binding protein-dna-rna complex, dna binding protein/dna/rna
• 由来する生物種: Thermobifida fusca (strain YX); 詳細
• タンパク質・核酸の鎖数: 15
• 化学式量合計: 575035.33

構造登録者

Xiao, Y.,Luo, M.,Liao, M.,Ke, A. (登録日: 2018-01-17, 公開日: 2018-06-27, 最終更新日: 2023-11-29)

主引用文献

Xiao, Y.,Luo, M.,Dolan, A.E.,Liao, M.,Ke, A.
Structure basis for RNA-guided DNA degradation by Cascade and Cas3.
Science, 361:-, 2018

PubMed Abstract: Type I CRISPR-Cas system features a sequential target-searching and degradation process on double-stranded DNA by the RNA-guided Cascade (CRISPR associated complex for antiviral defense) complex and the nuclease-helicase fusion enzyme Cas3, respectively. Here, we present a 3.7-angstrom-resolution cryo-electron microscopy (cryo-EM) structure of the Type I-E Cascade/R-loop/Cas3 complex, poised to initiate DNA degradation. Cas3 distinguishes Cascade conformations and only captures the R-loop-forming Cascade, to avoid cleaving partially complementary targets. Its nuclease domain recruits the nontarget strand (NTS) DNA at a bulged region for the nicking of single-stranded DNA. An additional 4.7-angstrom-resolution cryo-EM structure captures the postnicking state, in which the severed NTS retracts to the helicase entrance, to be threaded for adenosine 5'-triphosphate-dependent processive degradation. These snapshots form the basis for understanding RNA-guided DNA degradation in Type I-E CRISPR-Cas systems.

PubMed: 29880725
DOI: 10.1126/science.aat0839

実験手法

ELECTRON MICROSCOPY (3.66 Å)