8FTI

Cryo-EM structure of the Cas13bt3-crRNA-target RNA ternary complex in activated state

8FTI の概要

• エントリーDOI: 10.2210/pdb8fti/pdb
• EMDBエントリー: 29433
• 分子名称: Integrase, crRNA-linker-target hairpin RNA (2 entities in total)
• 機能のキーワード: cas13bt3-crrna-target rna ternary complex, activated state, rna binding protein, rna binding protein-rna complex, rna binding protein/rna
• 由来する生物種: Planctomycetota bacterium; 詳細
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 123390.14

構造登録者

Gao, Y.,Deng, X. (登録日: 2023-01-12, 公開日: 2023-09-27, 最終更新日: 2024-05-01)

主引用文献

Deng, X.,Osikpa, E.,Yang, J.,Oladeji, S.J.,Smith, J.,Gao, X.,Gao, Y.
Structural basis for the activation of a compact CRISPR-Cas13 nuclease.
Nat Commun, 14:5845-5845, 2023

PubMed Abstract: The CRISPR-Cas13 ribonucleases have been widely applied for RNA knockdown and transcriptional modulation owing to their high programmability and specificity. However, the large size of Cas13 effectors and their non-specific RNA cleavage upon target activation limit the adeno-associated virus based delivery of Cas13 systems for therapeutic applications. Herein, we report detailed biochemical and structural characterizations of a compact Cas13 (Cas13bt3) suitable for adeno-associated virus delivery. Distinct from many other Cas13 systems, Cas13bt3 cleaves the target and other nonspecific RNA at internal "UC" sites and is activated in a target length-dependent manner. The cryo-electron microscope structure of Cas13bt3 in a fully active state illustrates the structural basis of Cas13bt3 activation. Guided by the structure, we obtain engineered Cas13bt3 variants with minimal off-target cleavage yet maintained target cleavage activities. In conclusion, our biochemical and structural data illustrate a distinct mechanism for Cas13bt3 activation and guide the engineering of Cas13bt3 applications.

PubMed: 37730702
DOI: 10.1038/s41467-023-41501-5

実験手法

ELECTRON MICROSCOPY (3.5 Å)