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. 2025 Sep 10;33(9):1550-1560.e4.
doi: 10.1016/j.chom.2025.05.020. Epub 2025 Aug 18.

Crosstalk between three CRISPR-Cas types enables primed type VI-A adaptation in Listeria seeligeri

Shally R Margolis  1 , Alexander J Meeske  2
Affiliations

Crosstalk between three CRISPR-Cas types enables primed type VI-A adaptation in Listeria seeligeri

Shally R Margolis et al. Cell Host Microbe. .

Abstract

CRISPR-Cas systems confer adaptive immunity to their prokaryotic hosts through the process of adaptation, where sequences are captured from foreign nucleic acids and integrated as spacers in the CRISPR array, thereby enabling crRNA-guided interference against new threats. While the Cas1-2 integrase is critical for adaptation, it is absent from many CRISPR-Cas loci, rendering the mechanism of spacer acquisition unclear for these systems. In this study, we show that the RNA-targeting type VI-A CRISPR system of Listeria seeligeri acquires spacers from DNA substrates through the action of a promiscuous Cas1-2 integrase encoded by a co-occurring type II-C system, in a transcription-independent manner. We further demonstrate that the type II-C integration complex is strongly stimulated by preexisting spacers in a third CRISPR system (type I-B), which imperfectly match phage targets and prime type VI-A adaptation. Altogether, our results reveal an unprecedented degree of communication among CRISPR-Cas loci encoded by a single organism.

Keywords: CRISPR; Cas13; bacteriophage; primed adaptation; spacer acquisition.

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Conflict of interest statement

Declaration of interests A.J.M. is a co-founder and advisor of Profluent Bio.

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References

    1. Barrangou R, Fremaux C, Deveau H, Richards M, Boyaval P, Moineau S, Romero DA, and Horvath P (2007). CRISPR provides acquired resistance against viruses in prokaryotes. Science 315, 1709–1712. 10.1126/science.1138140. - DOI - PubMed
    1. Brouns SJ, Jore MM, Lundgren M, Westra ER, Slijkhuis RJ, Snijders AP, Dickman MJ, Makarova KS, Koonin EV, and van der Oost J (2008). Small CRISPR RNAs guide antiviral defense in prokaryotes. Science 321, 960–964. 10.1126/science.1159689. - DOI - PMC - PubMed
    1. Hale C, Kleppe K, Terns RM, and Terns MP (2008). Prokaryotic silencing (psi)RNAs in Pyrococcus furiosus. RNA 14, 2572–2579. 10.1261/rna.1246808. - DOI - PMC - PubMed
    1. Marraffini LA, and Sontheimer EJ (2008). CRISPR interference limits horizontal gene transfer in staphylococci by targeting DNA. Science 322, 1843–1845. 10.1126/science.1165771. - DOI - PMC - PubMed
    1. Garneau JE, Dupuis ME, Villion M, Romero DA, Barrangou R, Boyaval P, Fremaux C, Horvath P, Magadan AH, and Moineau S (2010). The CRISPR/Cas bacterial immune system cleaves bacteriophage and plasmid DNA. Nature 468, 67–71. 10.1038/nature09523. - DOI - PubMed

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