{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Zhou Y"],"funding":["NIGMS NIH HHS"],"pagination":["102201"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC7937560"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["24(3)"],"pubmed_abstract":["We reveal the cryo-electron microscopy structure of a type IV-B CRISPR ribonucleoprotein (RNP) complex (Csf) at 3.9-Å resolution. The complex best resembles the type III-A CRISPR Csm effector complex, consisting of a Cas7-like (Csf2) filament intertwined with a small subunit (Cas11) filament, but the complex lacks subunits for RNA processing and target DNA cleavage. Surprisingly, instead of assembling around a CRISPR-derived RNA (crRNA), the complex assembles upon heterogeneous RNA of a regular length arranged in a pseudo-A-form configuration. These findings provide a high-resolution glimpse into the assembly and function of enigmatic type IV CRISPR systems, expanding our understanding of class I CRISPR-Cas system architecture, and suggesting a function for type IV-B RNPs that may be distinct from other class 1 CRISPR-associated systems."],"journal":["iScience"],"pubmed_title":["Structure of a type IV CRISPR-Cas ribonucleoprotein complex."],"pmcid":["PMC7937560"],"funding_grant_id":["R35 GM138348","R35 GM138080"],"pubmed_authors":["Bravo JPK","Taylor DW","Taylor HN","Jackson RN","Steens JA","Zhou Y","Staals RHJ"],"additional_accession":[]},"is_claimable":false,"name":"Structure of a type IV CRISPR-Cas ribonucleoprotein complex.","description":"We reveal the cryo-electron microscopy structure of a type IV-B CRISPR ribonucleoprotein (RNP) complex (Csf) at 3.9-Å resolution. The complex best resembles the type III-A CRISPR Csm effector complex, consisting of a Cas7-like (Csf2) filament intertwined with a small subunit (Cas11) filament, but the complex lacks subunits for RNA processing and target DNA cleavage. Surprisingly, instead of assembling around a CRISPR-derived RNA (crRNA), the complex assembles upon heterogeneous RNA of a regular length arranged in a pseudo-A-form configuration. These findings provide a high-resolution glimpse into the assembly and function of enigmatic type IV CRISPR systems, expanding our understanding of class I CRISPR-Cas system architecture, and suggesting a function for type IV-B RNPs that may be distinct from other class 1 CRISPR-associated systems.","dates":{"release":"2021-01-01T00:00:00Z","publication":"2021 Mar","modification":"2026-04-16T15:04:37.444Z","creation":"2025-04-05T18:57:15.109Z"},"accession":"S-EPMC7937560","cross_references":{"pubmed":["33733066"],"doi":["10.1016/j.isci.2021.102201"]}}