Publication Date:
2014-08-16
Description:
In prokaryotes, RNA derived from type I and type III CRISPR loci direct large ribonucleoprotein complexes to destroy invading bacteriophage and plasmids. In Escherichia coli, this 405-kilodalton complex is called Cascade. We report the crystal structure of Cascade bound to a single-stranded DNA (ssDNA) target at a resolution of 3.03 angstroms. The structure reveals that the CRISPR RNA and target strands do not form a double helix but instead adopt an underwound ribbon-like structure. This noncanonical structure is facilitated by rotation of every sixth nucleotide out of the RNA-DNA hybrid and is stabilized by the highly interlocked organization of protein subunits. These studies provide insight into both the assembly and the activity of this complex and suggest a mechanism to enforce fidelity of target binding.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4427192/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉 〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4427192/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Mulepati, Sabin -- Heroux, Annie -- Bailey, Scott -- GM097330/GM/NIGMS NIH HHS/ -- P41GM103393/GM/NIGMS NIH HHS/ -- P41GM103473/GM/NIGMS NIH HHS/ -- P41RR012408/RR/NCRR NIH HHS/ -- R01 GM097330/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 2014 Sep 19;345(6203):1479-84. doi: 10.1126/science.1256996. Epub 2014 Aug 14.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA. ; Photon Sciences Directorate, Brookhaven National Laboratory, Upton, NY 11973, USA. ; Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA. scott.bailey@jhu.edu.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25123481" target="_blank"〉PubMed〈/a〉
Keywords:
CRISPR-Associated Proteins/*chemistry
;
*CRISPR-Cas Systems
;
*Clustered Regularly Interspaced Short Palindromic Repeats
;
Crystallography, X-Ray
;
DNA Helicases/chemistry
;
DNA, Single-Stranded/*chemistry
;
Escherichia coli/*genetics
;
Escherichia coli Proteins/*chemistry
;
Models, Molecular
;
RNA, Bacterial/*chemistry
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics