8W1P

Structure of Selenomonas sp. Cascade (SsCascade)

これはPDB形式変換不可エントリーです。

8W1P の概要

• エントリーDOI: 10.2210/pdb8w1p/pdb
• EMDBエントリー: 43729
• 分子名称: Cas7, Cas8, Cas5, ... (7 entities in total)
• 機能のキーワード: crispr-cas, genome engineering, rna-guided dna endonuclease, non-coding rna, hnh nuclease, immune system
• 由来する生物種: Selenomonas sp.; 詳細
• タンパク質・核酸の鎖数: 12
• 化学式量合計: 385780.21

構造登録者

Hirano, S.,Zhang, F. (登録日: 2024-02-16, 公開日: 2024-08-07, 最終更新日: 2024-09-11)

主引用文献

Hirano, S.,Altae-Tran, H.,Kannan, S.,Macrae, R.K.,Zhang, F.
Structural determinants of DNA cleavage by a CRISPR HNH-Cascade system.
Mol.Cell, 84:3154-, 2024

PubMed Abstract: Canonical prokaryotic type I CRISPR-Cas adaptive immune systems contain a multicomponent effector complex called Cascade, which degrades large stretches of DNA via Cas3 helicase-nuclease activity. Recently, a highly precise subtype I-F1 CRISPR-Cas system (HNH-Cascade) was found that lacks Cas3, the absence of which is compensated for by the insertion of an HNH endonuclease domain in the Cas8 Cascade component. Here, we describe the cryo-EM structure of Selenomonas sp. HNH-Cascade (SsCascade) in complex with target DNA and characterize its mechanism of action. The Cascade scaffold is complemented by the HNH domain, creating a ring-like structure in which the unwound target DNA is precisely cleaved. This structure visualizes a unique hybrid of two extensible biological systems-Cascade, an evolutionary platform for programmable DNA effectors, and an HNH nuclease, an adaptive domain with a spectrum of enzymatic activity.

PubMed: 39111310
DOI: 10.1016/j.molcel.2024.07.026

実験手法

ELECTRON MICROSCOPY (3.5 Å)