2015年5月
Crystal Structure of the CRISPR-Cas RNA Silencing Cmr Complex Bound to a Target Analog
MOLECULAR CELL
- ,
- ,
- ,
- 巻
- 58
- 号
- 3
- 開始ページ
- 418
- 終了ページ
- 430
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1016/j.molcel.2015.03.018
- 出版者・発行元
- CELL PRESS
In prokaryotes, Clustered regularly interspaced short palindromic repeat (CRISPR)-derived RNAs (crRNAs), together with CRISPR-associated (Cas) proteins, capture and degrade invading genetic materials. In the type III-B CRISPR-Cas system, six Cas proteins (Cmr1-Cmr6) and a crRNA form an RNA silencing Cmr complex. Here we report the 2.1 angstrom crystal structure of the Cmr1-deficient, functional Cmr complex bound to single-stranded DNA, a substrate analog complementary to the crRNA guide. Cmr3 recognizes the crRNA 5' tag and defines the start position of the guide-target duplex, using its idiosyncratic loops. The beta-hairpins of three Cmr4 subunits intercalate within the duplex, causing nucleotide displacements with 6 nt intervals, and thus periodically placing the scissile bonds near the crucial aspartate of Cmr4. The structure reveals the mechanism for specifying the periodic target cleavage sites from the crRNA 5' tag and provides insights into the assembly of the type III interference machineries and the evolution of the Cmr and Cascade complexes.
- リンク情報
- ID情報
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- DOI : 10.1016/j.molcel.2015.03.018
- ISSN : 1097-2765
- eISSN : 1097-4164
- PubMed ID : 25921071
- Web of Science ID : WOS:000354178800005