Structural basis of AtCas9 recognition of PAM mutants in underwound DNA topology.

Min Duan, Bing Meng, Lei Zhou, Lijie Wu, Xiaohan Tong, Dongchao Huang, Hao Yin, Zhi-Jie Liu, Ying Zhang

Abstract read

In one paragraph

Article in Nature structural & molecular biology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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4 · The record

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5 · Who and what money

Authors and funding

9 authors.

Min Duan *Department of Rheumatology and Immunology, Medical Research Institute, Frontier Science Center for Immunology and Metabolism, Zhongnan Hospital of Wuhan University, State Key Laboratory of Virology and Biosafety, Wuhan University, Wuhan, China. minduan@whu.edu.cn.ORCID http://orcid.org/0000-0002-9017-7576

Bing Meng *iHuman Institute, ShanghaiTech University, Shanghai, China.ORCID http://orcid.org/0000-0001-9076-2946

Lei Zhou *Department of Rheumatology and Immunology, Medical Research Institute, Frontier Science Center for Immunology and Metabolism, Zhongnan Hospital of Wuhan University, State Key Laboratory of Virology and Biosafety, Wuhan University, Wuhan, China.

Lijie WuiHuman Institute, ShanghaiTech University, Shanghai, China.ORCID http://orcid.org/0000-0002-2253-0497

Xiaohan TongDepartment of Rheumatology and Immunology, Medical Research Institute, Frontier Science Center for Immunology and Metabolism, Zhongnan Hospital of Wuhan University, State Key Laboratory of Virology and Biosafety, Wuhan University, Wuhan, China.

Dongchao HuangDepartment of Rheumatology and Immunology, Medical Research Institute, Frontier Science Center for Immunology and Metabolism, Zhongnan Hospital of Wuhan University, State Key Laboratory of Virology and Biosafety, Wuhan University, Wuhan, China.

Hao YinDepartment of Rheumatology and Immunology, Medical Research Institute, Frontier Science Center for Immunology and Metabolism, Zhongnan Hospital of Wuhan University, State Key Laboratory of Virology and Biosafety, Wuhan University, Wuhan, China.ORCID http://orcid.org/0000-0001-9654-5985

Zhi-Jie LiuiHuman Institute, ShanghaiTech University, Shanghai, China.ORCID http://orcid.org/0000-0001-7279-2893

Ying ZhangDepartment of Rheumatology and Immunology, Medical Research Institute, Frontier Science Center for Immunology and Metabolism, Zhongnan Hospital of Wuhan University, State Key Laboratory of Virology and Biosafety, Wuhan University, Wuhan, China. ying.zhang84@whu.edu.cn.ORCID http://orcid.org/0000-0003-4044-0230

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

The CRISPR-Cas9 system locates targets through guide RNA pairing and recognition of a protospacer-adjacent motif (PAM). Although PAM specificity is sequence-determined, DNA topology can relax PAM requirements and enable near-PAMless cleavage by the type II-C Alicyclobacillus tengchongensis Cas9 (AtCas9). However, the structural mechanism underlying this regulation remains unknown. Here we report cryogenic-electron microscopy (cryo-EM) structures of AtCas9 bound to B-form DNA or a 340 bp underwound minicircle DNA containing wild-type or mutant PAMs. Despite PAM sequences differences, all three underwound complexes adopt an almost identical architecture distinct from the B-form DNA-bound state. On B-form DNA, AtCas9 recognizes the PAM through base-specific hydrogen bonds and steric exclusion, conferring preference for N

Indexed as

AlicyclobacillusCRISPR-Associated ProteinsDNACRISPR-Cas SystemsCryoelectron MicroscopyModels, MolecularMutationNucleic Acid ConformationCRISPR-Associated ProteinsDNA

Identifiers

PMID42342973

DOI10.1093/nar/gkm216

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.