2. Academic Validation
  3. A miniature CRISPR-Cas10 enzyme confers immunity by inhibitory signalling

A miniature CRISPR-Cas10 enzyme confers immunity by inhibitory signalling

  • Nature. 2025 Oct 1. doi: 10.1038/s41586-025-09569-9.
Erin E Doherty # 1 2 3,  Benjamin A Adler # 1 2 3,  Peter H Yoon 1 2,  Kendall Hsieh 2,  Kenneth Loi 2,  Emily G Armbruster 4,  Arushi Lahiri 2,  Cydni S Bolling 1,  Xander E Wilcox 5,  Amogha Akkati 6,  Anthony T Iavarone 3,  Joe Pogliano 4,  Jennifer A Doudna 7 8 9 10 11 12 13
Affiliations

Affiliations

  • 1 Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA, USA.
  • 2 Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA.
  • 3 California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, CA, USA.
  • 4 School of Biological Sciences, University of California San Diego, La Jolla, CA, USA.
  • 5 Department of Microbiology and Immunology, Cornell University, Ithaca, NY, USA.
  • 6 Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, USA.
  • 7 Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA, USA. doudna@berkeley.edu.
  • 8 Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA. doudna@berkeley.edu.
  • 9 California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, CA, USA. doudna@berkeley.edu.
  • 10 Gladstone Institutes, University of California, San Francisco, San Francisco, CA, USA. doudna@berkeley.edu.
  • 11 Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA, USA. doudna@berkeley.edu.
  • 12 Department of Chemistry, University of California, Berkeley, Berkeley, CA, USA. doudna@berkeley.edu.
  • 13 MBIB Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA. doudna@berkeley.edu.
  • # Contributed equally.
PMID: 41034576 DOI: 10.1038/s41586-025-09569-9
Abstract

Microbial and viral co-evolution has created immunity mechanisms involving oligonucleotide signalling that share mechanistic features with human Antiviral systems1. In these pathways, including cyclic oligonucleotide-based antiphage signalling systems (CBASSs) and type III CRISPR systems in bacteria and cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) in humans, oligonucleotide synthesis occurs upon detection of virus or foreign genetic material in the cell, triggering the Antiviral response2-4. Here, in an unexpected inversion of this process, we show that the CRISPR-related enzyme mCpol synthesizes cyclic oligonucleotides constitutively as part of an active mechanism that represses a toxic effector. Cell-based experiments demonstrated that the absence or loss of mCpol-produced cyclic oligonucleotides triggers cell death, preventing the spread of viruses that attempt immune evasion by depleting host cyclic nucleotides. Structural and mechanistic investigation revealed mCpol to be a di-adenylate cyclase whose product, c-di-AMP, prevents toxic oligomerization of the effector protein 2TMβ. Analysis of cells by fluorescence microscopy showed that lack of mCpol allows 2TMβ-mediated cell death due to inner membrane collapse. These findings unveil a powerful defence strategy against virus-mediated immune suppression, expanding our understanding of the role of oligonucleotides in immunity.

Figures
Products