8JFT

Cryo-EM structure of SaCas9-AcrIIA15 CTD-sgRNA complex

8JFT の概要

• エントリーDOI: 10.2210/pdb8jft/pdb
• EMDBエントリー: 36217
• 分子名称: CRISPR-associated endonuclease Cas9, sgRNA of SaCas9, AcrIIA15 (3 entities in total)
• 機能のキーワード: ii-a type anti-crispr protein, viral protein
• 由来する生物種: Staphylococcus aureus; 詳細
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 169250.80

構造登録者

Deng, X.,Wang, Y. (登録日: 2023-05-18, 公開日: 2024-02-28, 最終更新日: 2024-09-11)

主引用文献

Deng, X.,Sun, W.,Li, X.,Wang, J.,Cheng, Z.,Sheng, G.,Wang, Y.
An anti-CRISPR that represses its own transcription while blocking Cas9-target DNA binding.
Nat Commun, 15:1806-1806, 2024

PubMed Abstract: AcrIIA15 is an anti-CRISPR (Acr) protein that inhibits Staphylococcus aureus Cas9 (SaCas9). Although previous studies suggested it has dual functions, the structural and biochemical basis for its two activities remains unclear. Here, we determined the cryo-EM structure of AcrIIA15 in complex with SaCas9-sgRNA to reveal the inhibitory mechanism of the Acr's C-terminal domain (CTD) in mimicking dsDNA to block protospacer adjacent motif (PAM) recognition. For the N-terminal domain (NTD), our crystal structures of the AcrIIA15-promoter DNA show that AcrIIA15 dimerizes through its NTD to recognize double-stranded (ds) DNA. Further, AcrIIA15 can simultaneously bind to both SaCas9-sgRNA and promoter DNA, creating a supercomplex of two Cas9s bound to two CTDs converging on a dimer of the NTD bound to a dsDNA. These findings shed light on AcrIIA15's inhibitory mechanisms and its autoregulation of transcription, enhancing our understanding of phage-host interactions and CRISPR defense.

PubMed: 38418450
DOI: 10.1038/s41467-024-45987-5

実験手法

ELECTRON MICROSCOPY (3.31 Å)