Structural organization of a Type III-A CRISPR effector subcomplex determined by X-ray crystallography and cryo-EM
Year: 2019
Type: article
Abstract: Clustered regularly interspaced short palindromic repeats (CRISPR) and their associated Cas proteins provide an immune-like response in many prokaryotes against extraneous nucleic acids. CRISPR-Cas systems are classified into different classes and types. Class 1 CRISPR-Cas systems form multi-protein effector complexes that includes a guide RNA (crRNA) used to identify the target for destruction. Here we present crystal structures of Staphylococcus epidermidis Type III-A CRISPR subunits Csm2 and Csm3 and a 5.2 Å resolution single-particle cryo-electron microscopy (cryo-EM) reconstruction of an in vivo assembled effector subcomplex including the crRNA. The structures help to clarify the quaternary architecture of Type III-A effector complexes, and provide details on crRNA binding, target RNA binding and cleavage, and intermolecular interactions essential for effector complex assembly. The structures allow a better understanding of the organization of Type III-A CRISPR effector complexes as well as highlighting the overall similarities and differences with other Class 1 effector complexes.
Source: Nucleic Acids Research
DOI: 10.1093/nar/gkz079
Authors: Bryan W Dorsey, Lei Huang, Alfonso Mondragón
Institution: Northwestern University
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $3,992
Funders: Chicago Community Trust, Michigan Economic Development Corporation, Northwestern University, National Institutes of Health, Michigan Technology Tri-Corridor, National Cancer Institute, National Institute of General Medical Sciences, National Center for Research Resources, Argonne National Laboratory
OpenAlex ID: W2897114239