Structural biology. Crystal structure of the CRISPR RNA-guided surveillance complex from Escherichia coli.
Science
; 345(6203): 1473-9, 2014 Sep 19.
Article
en En
| MEDLINE
| ID: mdl-25103409
ABSTRACT
Clustered regularly interspaced short palindromic repeats (CRISPRs) are essential components of RNA-guided adaptive immune systems that protect bacteria and archaea from viruses and plasmids. In Escherichia coli, short CRISPR-derived RNAs (crRNAs) assemble into a 405-kilodalton multisubunit surveillance complex called Cascade (CRISPR-associated complex for antiviral defense). Here we present the 3.24 angstrom resolution x-ray crystal structure of Cascade. Eleven proteins and a 61-nucleotide crRNA assemble into a seahorse-shaped architecture that binds double-stranded DNA targets complementary to the crRNA-guide sequence. Conserved sequences on the 3' and 5' ends of the crRNA are anchored by proteins at opposite ends of the complex, whereas the guide sequence is displayed along a helical assembly of six interwoven subunits that present five-nucleotide segments of the crRNA in pseudo-A-form configuration. The structure of Cascade suggests a mechanism for assembly and provides insights into the mechanisms of target recognition.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Contexto en salud:
3_ND
Problema de salud:
3_neglected_diseases
/
3_zoonosis
Asunto principal:
ARN Bacteriano
/
Proteínas de Escherichia coli
/
Escherichia coli
/
Proteínas Asociadas a CRISPR
/
Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas
/
Sistemas CRISPR-Cas
Tipo de estudio:
Screening_studies
Idioma:
En
Revista:
Science
Año:
2014
Tipo del documento:
Article
País de afiliación:
Estados Unidos