タンパク質・ペプチド: CRISPR type I-F/YPEST-associated protein Csy2
タンパク質・ペプチド: CRISPR-associated protein Csy3
タンパク質・ペプチド: AcrIF5
タンパク質・ペプチド: type I-F CRISPR-associated endoribonuclease Cas6/Csy4
RNA: RNA (60-MER)
タンパク質・ペプチド: Type I-F CRISPR-associated protein Csy1
複合体: DNA
DNA: DNA (54-MER)
DNA: DNA (54-MER)
キーワード
complex / inhibitor / IMMUNE SYSTEM / IMMUNE SYSTEM-RNA-DNA complex
機能・相同性
機能・相同性情報
CRISPR-associated protein Csy1 / CRISPR-associated protein (Cas_Csy1) / CRISPR-associated protein Csy2 / CRISPR-associated protein (Cas_Csy2) / CRISPR-associated protein Csy3 / CRISPR-associated protein (Cas_Csy3) 類似検索 - ドメイン・相同性
Uncharacterized protein / CRISPR-associated protein Csy3 / : / Uncharacterized protein 類似検索 - 構成要素
ジャーナル: Nat Chem Biol / 年: 2022 タイトル: AcrIF5 specifically targets DNA-bound CRISPR-Cas surveillance complex for inhibition. 著者: Yongchao Xie / Laixing Zhang / Zhengyu Gao / Peipei Yin / Hao Wang / Hang Li / Zeliang Chen / Yi Zhang / Maojun Yang / Yue Feng / 要旨: CRISPR-Cas systems are prokaryotic antiviral systems, and phages use anti-CRISPR proteins (Acrs) to inactivate these systems. Here we present structural and functional analyses of AcrIF5, exploring ...CRISPR-Cas systems are prokaryotic antiviral systems, and phages use anti-CRISPR proteins (Acrs) to inactivate these systems. Here we present structural and functional analyses of AcrIF5, exploring its unique anti-CRISPR mechanism. AcrIF5 shows binding specificity only for the target DNA-bound form of the crRNA-guided surveillance (Csy) complex, but not the apo Csy complex from the type I-F CRISPR-Cas system. We solved the structure of the Csy-dsDNA-AcrIF5 complex, revealing that the conformational changes of the Csy complex caused by dsDNA binding dictate the binding specificity for the Csy-dsDNA complex by AcrIF5. Mechanistically, five AcrIF5 molecules bind one Csy-dsDNA complex, which destabilizes the helical bundle domain of Cas8f, thus preventing subsequent Cas2/3 recruitment. AcrIF5 exists in symbiosis with AcrIF3, which blocks Cas2/3 recruitment. This attack on the recruitment event stands in contrast to the conventional mechanisms of blocking binding of target DNA. Overall, our study reveals an unprecedented mechanism of CRISPR-Cas inhibition by AcrIF5.