PAM-Dependent Target DNA Recognition and Cleavage by C2c1 CRISPR-Cas Endonuclease.
Cell
; 167(7): 1814-1828.e12, 2016 Dec 15.
Article
em En
| MEDLINE
| ID: mdl-27984729
ABSTRACT
C2c1 is a newly identified guide RNA-mediated type V-B CRISPR-Cas endonuclease that site-specifically targets and cleaves both strands of target DNA. We have determined crystal structures of Alicyclobacillus acidoterrestris C2c1 (AacC2c1) bound to sgRNA as a binary complex and to target DNAs as ternary complexes, thereby capturing catalytically competent conformations of AacC2c1 with both target and non-target DNA strands independently positioned within a single RuvC catalytic pocket. Moreover, C2c1-mediated cleavage results in a staggered seven-nucleotide break of target DNA. crRNA adopts a pre-ordered five-nucleotide A-form seed sequence in the binary complex, with release of an inserted tryptophan, facilitating zippering up of 20-bp guide RNAtarget DNA heteroduplex on ternary complex formation. Notably, the PAM-interacting cleft adopts a "locked" conformation on ternary complex formation. Structural comparison of C2c1 ternary complexes with their Cas9 and Cpf1 counterparts highlights the diverse mechanisms adopted by these distinct CRISPR-Cas systems, thereby broadening and enhancing their applicability as genome editing tools.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Endodesoxirribonucleases
/
Alicyclobacillus
/
Sistemas CRISPR-Cas
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
Cell
Ano de publicação:
2016
Tipo de documento:
Article