CRISPR-Cas III-A Csm6 CARF Domain Is a Ring Nuclease Triggering Stepwise cA4 Cleavage with ApA>p Formation Terminating RNase Activity.

@article{Jia2019CRISPRCasIC,
  title={CRISPR-Cas III-A Csm6 CARF Domain Is a Ring Nuclease Triggering Stepwise cA4 Cleavage with ApA>p Formation Terminating RNase Activity.},
  author={N. Jia and Roger A. Jones and G. Yang and O. Ouerfelli and D. Patel},
  journal={Molecular cell},
  year={2019}
}
Type III-A CRISPR-Cas surveillance complexes containing multi-subunit Csm effector, guide, and target RNAs exhibit multiple activities, including formation of cyclic-oligoadenylates (cAn) from ATP and subsequent cAn-mediated cleavage of single-strand RNA (ssRNA) by the trans-acting Csm6 RNase. Our structure-function studies have focused on Thermococcus onnurineus Csm6 to deduce mechanistic insights into how cA4 binding to the Csm6 CARF domain triggers the RNase activity of the Csm6 HEPN domain… Expand
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The structure of Sulfolobus islandicus (Sis) Csx1-cOA4 complex is presented, which forms a hexamer and an allosteric mechanism for the activation of CsX1 RNase is revealed, suggesting that this enzyme could be employed in biotechnological applications. Expand
Second Messenger cA4 Formation within the Composite Csm1 Palm Pocket of Type III-A CRISPR-Cas Csm Complex and Its Release Path.
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Structural results from cryo-EM and X-ray studies on multi-subunit Thermococcus onnurineus Csm effector ternary complexes are combined with published functional studies to highlight mechanistic insights into the role of the CSm effector complex in mediating the cAn signaling pathway. Expand
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TLDR
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TLDR
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