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

  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},

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

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

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

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.

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

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

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

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.



Programmable RNA targeting with the single-protein CRISPR effector Cas7-11.

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

Biogenesis pathways of RNA guides in archaeal and bacterial CRISPR-Cas adaptive immunity

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

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

It is demonstrated that the Cas9–crRNA complex of the Streptococcus thermophilus CRISPR3/Cas system introduces in vitro a double-strand break at a specific site in DNA containing a sequence complementary to crRNA, paving the way for engineering of universal programmable RNA-guided DNA endonucleases.

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

A type III-E effector from Candidatus “Scalindua brodae” (Sb-gRAMP), which is natively encoded by a single gene with several type III domains fused together, is described, suggesting a potential mechanism of target RNA–induced protease activity to gain viral immunity.