Structure and engineering of the type III-E CRISPR-Cas7-11 effector complex

@article{Kato2022StructureAE,
  title={Structure and engineering of the type III-E CRISPR-Cas7-11 effector complex},
  author={Kazuki Kato and Wenyuan Zhou and Sae Okazaki and Yukari Isayama and Tomohiro Nishizawa and Jonathan S. Gootenberg and Omar O. Abudayyeh and Hiroshi Nishimasu},
  journal={Cell},
  year={2022},
  volume={185},
  pages={2324-2337.e16}
}

Structural and functional insights into the type III-E CRISPR-Cas immunity

TLDR
A series of structures of gRAMP-crRNA, either its alone or in complex with target RNA or TPR-CHAT, and Craspase complexed with cognate (CTR) or non-cognate target RNA (NTR) are reported, providing crucial insights into both the catalytic mechanism and immunity mechanism of the type III-E CRISPR-Cas system.

Cryo-EM structure of the type III-E CRISPR-Cas effector gRAMP in complex with TPR-CHAT

TLDR
The mechanism of recognition of crRNA and target ssRNA by gRAMP is revealed and the structure of the CRISPR type III-E effector in complex with the binding partner TPR-CHAT is reported, which provides vital clues for elucidating the functional relation between theCRISPR-Cas system and caspase peptidase.

RNA-triggered protein cleavage and cell death by the RNA-guided type III-E CRISPR-Cas nuclease-protease complex

TLDR
Cryo-electron microscopy structures of the Cas7-11–crRNA–Csx29 complex with and without target RNA are reported, and it is demonstrated that target RNA binding induces a conformational change in Csx29 and results in the protease activation.

Craspase is a CRISPR RNA-guided, RNA-activated protease.

TLDR
Cryo-electron microscopy snapshots of Craspase are used to explain its target RNA cleavage and protease activation mechanisms and it is concluded that Craspases is a target RNA-activated protease with self-regulatory capacity.

Structural rearrangements of a caspase-like protease TPR-CHAT govern virus-host discrimination during type III-E CRISPR-Caspase immunity

TLDR
Cryo-EM structures of gRAMPcrRNA and gRampcrRNA-TPR-CHAT complexes are reported, elucidating mechanisms underlying RNA-targeting and non-self RNA-induced protease activation, and implicate an ancient mechanism for separase regulation.

Deep learning and CRISPR-Cas13d ortholog discovery for optimized RNA targeting

TLDR
The Cas13d guide efficiency model successfully generalized to DjCas13d, highlighting the utility of a comprehensive approach combining machine learning with ortholog discovery to advance RNA targeting in human cells.

Assembly of multi-subunit fusion proteins into the RNA-targeting type III-D CRISPR-Cas effector complex

TLDR
These findings provide insights into how multi-subunit fusion proteins are tethered together and assemble into an active and programmable RNA endonuclease, how the effector utilizes a novel mechanism for target RNA seeding, and the structural basis for the evolution of type III effector complexes.

References

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TLDR
The evolution of a single-protein effector from multisubunit class 1 effector complexes is illustrated, expanding the understanding of the diversity of CRISPR systems.

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TLDR
A detailed comparative analysis of pre-crRNA recognition and cleavage mechanisms involved in the biogenesis of guide crRNAs in the three CRISPR-Cas types is presented.

Structures of the CRISPR-Cmr complex reveal mode of RNA target positioning

TLDR
Near-atomic resolution cryo–electron microscopy reconstructions of native type III Cmr (CRISPR RAMP module) complexes in the absence and presence of target RNA reveal a helical protein arrangement that positions the crRNA for substrate binding.

Cas9–crRNA ribonucleoprotein complex mediates specific DNA cleavage for adaptive immunity in bacteria

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The gRAMP CRISPR-Cas effector is an RNA endonuclease complexed with a caspase-like peptidase

TLDR
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