@article{9af1b6d89deb409b9d7667403936afc3,
title = "Structure and Activity of the RNA-Targeting Type III-B CRISPR-Cas Complex of Thermus thermophilus",
abstract = "The CRISPR-Cas system is a prokaryotic host defense system against genetic elements. The Type III-B CRISPR-Cas system of the bacterium Thermus thermophilus, the TtCmr complex, is composed of six different protein subunits (Cmr1-6) and one crRNA with a stoichiometry of Cmr112131445361:crRNA1. The TtCmr complex copurifies with crRNA species of 40 and 46 nt, originating from a distinct subset of CRISPR loci and spacers. The TtCmr complex cleaves the target RNA at multiple sites with 6 nt intervals via a 5' ruler mechanism. Electron microscopy revealed that the structure of TtCmr resembles a {"}sea worm{"} and is composed of a Cmr2-3 heterodimer{"}tail,{"} a helical backbone of Cmr4 subunits capped by Cmr5 subunits, and a curled {"}head{"} containing Cmr1 and Cmr6. Despite having a backbone of only four Cmr4 subunits and being both longer and narrower, the overall architecture of TtCmr resembles that of Type I Cascade complexes.",
author = "Staals, {Raymond H.J.} and Yoshihiro Agari and Saori Maki-Yonekura and Yifan Zhu and Taylor, {David W.} and Esther vanDuijn and Arjan Barendregt and Marnix Vlot and Koehorst, {Jasper J.} and Keiko Sakamoto and Akiko Masuda and Naoshi Dohmae and Schaap, {Peter J.} and Doudna, {Jennifer A.} and Heck, {Albert J.R.} and Koji Yonekura and {Van der Oost}, John and Akeo Shinkai",
note = "Funding Information: We thank Aimi Osaki for construction of the recombinant T. thermophilus strain, Kayoko Matsumoto and Toshi Arima for purification of the Cmr proteins, Drs. Kwang Kim and Seiki Kuramitsu for identification of the Cmr subunits by the MS/MS analysis, and Aaron Jansen for his help with the activity assays. E. Nogales, H.-W. Wang, P. Grob, and T. Houweling are acknowledged for assistance with EM and image-processing. This work was supported by a Grant-in-Aid for Scientific Research (C), 25440013, from the Ministry of Education, Culture, Sports, Science and Technology, Japan (to A.S.), and by an ALW grant (820.02.003 to J.v.d.O.) from the Netherlands Organization for Scientific Research (N.W.O.). E.v.D., A.B., and A.J.R.H. were supported by the Netherlands Proteomics Centre. D.W.T. is a National Science Foundation Graduate Research Fellow, and J.A.D. is a Howard Hughes Medical Institute Investigator. ",
year = "2013",
month = oct,
day = "10",
doi = "10.1016/j.molcel.2013.09.013",
language = "English",
volume = "52",
pages = "135--145",
journal = "Molecular Cell",
issn = "1097-2765",
publisher = "Cell Press",
number = "1",
}