@article{27eddec3f1bd4381a0790f6d60f39398,
title = "Structural organization of a Type III-A CRISPR effector subcomplex determined by X-ray crystallography and cryo-EM",
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 {\AA} 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.",
author = "Dorsey, {Bryan W.} and Lei Huang and Alfonso Mondrag{\'o}n",
note = "Funding Information: We thank members of the Mondrag{\'o}n laboratory for discussions and assistance. We thank Kasia Soczek and Jonathan Remis for help with cryo-EM data collection. We are grateful to Asma Hatoum-Aslan for providing the Staphylococcus epidermidis strains used for this project. We acknowledge help and discussions with Erik Sontheimer in the early stages of the project. Research was supported by the NIH (A.M., grant R35-GM118108). We acknowledge Funding Information: National Institutes of Health (NIH) [R35 GM118108 to A.M.]; LS-CAT/Sector 21 at the Advanced Photon Source, Argonne National Laboratory was supported by the Michigan Economic Development Corporation and the Michigan Technology Tri-Corridor. Support from the R.H. Lurie Comprehensive Cancer Center of Northwestern University to the Structural Biology, Keck Biophysics, and High Throughput Analysis Facilities is acknowledged. The Gatan K2 DDE at Northwestern University was purchased with funds provided by the Chicago Biomedical Consortium with support from the Searle Funds at The Chicago Community Trust. The GE Healthcare Typhoon 9400 Flu-orimager at Northwestern University was purchased with funds provided by award [S10RR027842] from the National Center for Research Resources. Funding for open access charge: National Institutes of Health [R35 GM118108]. Conflict of interest statement. None declared. Publisher Copyright: {\textcopyright} The Author(s) 2019. Published by Oxford University Press on behalf of Nucleic Acids Research.",
year = "2019",
month = apr,
day = "23",
doi = "10.1093/nar/gkz079",
language = "English (US)",
volume = "47",
pages = "3765--3783",
journal = "Nucleic Acids Research",
issn = "0305-1048",
publisher = "Oxford University Press",
number = "7",
}