ArticleNature communications2025
Structure and mechanism of the broad spectrum CRISPR-associated ring nuclease Crn4.
Article in Nature communications, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
3 citing papers in PubMed.
- Cyclic tri-adenylate controls a CARF-TM effector in type II Panoptes anti-phage systems.PLoS biology · 2026Article
- The CRISPR ring nuclease Csx15 oligomerises on cyclic nucleotide binding to regulate antiviral defence.The Biochemical journal · 2026Article
- A viral SAVED protein with ring nuclease activity degrades the CRISPR second messenger cA4.The Biochemical journal · 2025Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
6 authors.
Funding
Abstract
Type III CRISPR systems detect the presence of RNA from mobile genetic elements (MGE) in prokaryotes, providing antiviral immunity. On activation, the catalytic Cas10 subunit conjugates ATP to form cyclic oligoadenylate (cOA) signalling molecules that activate ancillary effectors, providing an immune response. Cellular ring nucleases degrade cOA to reset the system. Here, we describe the structure and mechanism of a new family of ring nucleases, Crn4, associated with type III-D CRISPR systems. The crystal structure of Crn4 reveals a small homodimeric protein with a fold unrelated to any known ring nuclease or, indeed, any known protein structure. Crn4 degrades a wide range of cOA species to linear oligoadenylates in vitro and ameliorates type III CRISPR immunity in vivo. Phage and plasmids also encode Crn4 orthologues that may function as anti-CRISPRs. These observations expand our understanding of ring nucleases and reveal a new protein fold for cyclic nucleotide recognition.
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Registered trials
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