6IV6

Cryo-EM structure of AcrVA5-acetylated MbCas12a in complex with crRNA

6IV6 の概要

• エントリーDOI: 10.2210/pdb6iv6/pdb
• EMDBエントリー: 9742
• 分子名称: nuclease, RNA (59-MER) (2 entities in total)
• 機能のキーワード: enzyme, immune system, immune system-rna complex, immune system/rna
• 由来する生物種: Moraxella bovoculi; 詳細
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 163927.29

構造登録者

Dong, L.,Li, N.,Guan, X.,Zhu, Y.,Gao, N.,Huang, Z. (登録日: 2018-12-02, 公開日: 2019-04-10, 最終更新日: 2025-07-02)

主引用文献

Dong, L.,Guan, X.,Li, N.,Zhang, F.,Zhu, Y.,Ren, K.,Yu, L.,Zhou, F.,Han, Z.,Gao, N.,Huang, Z.
An anti-CRISPR protein disables type V Cas12a by acetylation.
Nat. Struct. Mol. Biol., 26:308-314, 2019

PubMed Abstract: Phages use anti-CRISPR proteins to deactivate the CRISPR-Cas system. The mechanisms for the inhibition of type I and type II systems by anti-CRISPRs have been elucidated. However, it has remained unknown how the type V CRISPR-Cas12a (Cpf1) system is inhibited by anti-CRISPRs. Here we identify the anti-CRISPR protein AcrVA5 and report the mechanisms by which it inhibits CRISPR-Cas12a. Our structural and biochemical data show that AcrVA5 functions as an acetyltransferase to modify Moraxella bovoculi (Mb) Cas12a at Lys635, a residue that is required for recognition of the protospacer-adjacent motif. The AcrVA5-mediated modification of MbCas12a results in complete loss of double-stranded DNA (dsDNA)-cleavage activity. In contrast, the Lys635Arg mutation renders MbCas12a completely insensitive to inhibition by AcrVA5. A cryo-EM structure of the AcrVA5-acetylated MbCas12a reveals that Lys635 acetylation provides sufficient steric hindrance to prevent dsDNA substrates from binding to the Cas protein. Our study reveals an unprecedented mechanism of CRISPR-Cas inhibition and suggests an evolutionary arms race between phages and bacteria.

PubMed: 30936526
DOI: 10.1038/s41594-019-0206-1

実験手法

ELECTRON MICROSCOPY (3.6 Å)