Structural basis of AcrIF24 as an anti-CRISPR protein and transcriptional suppressor.
Structural basis of AcrIF24 as an anti-CRISPR protein and transcriptional suppressor.
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DOI：
10.1038/s41589-022-01137-w
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发表时间：
2022-12
影响因子：
14.8
通讯作者：
Chang, Leifu
中科院分区：
文献类型：
--
作者：
Mukherjee, Indranil Arun;Gabel, Clinton;Noinaj, Nicholas;Bondy-Denomy, Joseph;Chang, Leifu
抗CRISPR（Acr）蛋白由细菌和古细菌的CRISPR-Cas系统编码，并用于增强CRISPR工具箱进行基因组编辑。在这里，我们报告了AcrIF 24的结构和机制，Acr蛋白抑制铜绿假单胞菌的I-F型CRISPR-Cas系统。AcrIF 24是一种同源二聚体，与两个拷贝的监视复合物（Csy）缔合，并阻止crRNA与靶DNA之间的杂交。此外，AcrIF 24作为抗CRISPR相关（Aca）蛋白发挥作用以抑制acrIF 23-acrIF 24操纵子的转录。单独或与Csy复合，AcrIF 24能够以纳摩尔亲和力结合acrIF 23-acrIF 24启动子DNA。Csy-AcrIF 24-启动子DNA复合物在2.7 nm处的结构揭示了转录抑制的机制。我们的研究结果表明，AcrIF 24作为Acr-Aca融合蛋白的功能，并扩展了我们对Acr蛋白所利用的不同机制的理解。EMukherjee等人报道了AcrIF 24是Acr-Aca融合蛋白，其抑制Csy复合物并抑制acrIF 23-acrIF 24启动子的转录，并提供了cryo-EM结构以揭示AcrIF 24的两种作用的机制。
Anti-CRISPR (Acr) proteins are encoded by phages to inactivate CRISPR-Cas systems of bacteria and archaea and are used to enhance the CRISPR toolbox for genome editing. Here we report the structure and mechanism of AcrIF24, an Acr protein that inhibits the type I-F CRISPR–Cas system from Pseudomonas aeruginosa. AcrIF24 is a homodimer that associates with two copies of the surveillance complex (Csy), and prevents the hybridization between crRNA and target DNA. Furthermore, AcrIF24 functions as an anti-CRISPR-associated (Aca) protein to repress the transcription of the acrIF23-acrIF24 operon. Alone or in complex with Csy, AcrIF24 is capable of binding to the acrIF23-acrIF24 promoter DNA with nanomolar affinity. The structure of a Csy–AcrIF24–promoter DNA complex at 2.7 Å reveals the mechanism for transcriptional suppression. Our results reveal that AcrIF24 functions as an Acr-Aca fusion protein and extend our understanding of the diverse mechanisms utilized by Acr proteins. EMukherjee et al. report that AcrIF24 is an Acr-Aca fusion protein, which inhibits the Csy complex and suppresses transcription from the acrIF23–acrIF24 promoter, and present cryo-EM structures to reveal the mechanism for both roles of AcrIF24.
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影响因子：
64.8
作者：
Jumper J;Evans R;Pritzel A;Green T;Figurnov M;Ronneberger O;Tunyasuvunakool K;Bates R;Žídek A;Potapenko A;Bridgland A;Meyer C;Kohl SAA;Ballard AJ;Cowie A;Romera-Paredes B;Nikolov S;Jain R;Adler J;Back T;Petersen S;Reiman D;Clancy E;Zielinski M;Steinegger M;Pacholska M;Berghammer T;Bodenstein S;Silver D;Vinyals O;Senior AW;Kavukcuoglu K;Kohli P;Hassabis D
通讯作者：
Hassabis D
影响因子：
14.9
作者：
Lavery R;Moakher M;Maddocks JH;Petkeviciute D;Zakrzewska K
通讯作者：
Zakrzewska K
影响因子：
64.8
作者：
Bondy-Denomy J;Garcia B;Strum S;Du M;Rollins MF;Hidalgo-Reyes Y;Wiedenheft B;Maxwell KL;Davidson AR
通讯作者：
Davidson AR
影响因子：
14.9
作者：
Birkholz, Nils;Fagerlund, Robert D.;Fineran, Peter C.
通讯作者：
Fineran, Peter C.
影响因子：
6.1
作者：
Kozin, MB;Svergun, DI
通讯作者：
Svergun, DI