Structural Basis for the Canonical and Non-canonical PAM Recognition by CRISPR-Cpf1.
Mol Cell
; 67(4): 633-645.e3, 2017 Aug 17.
Article
em En
| MEDLINE
| ID: mdl-28781234
ABSTRACT
The RNA-guided Cpf1 (also known as Cas12a) nuclease associates with a CRISPR RNA (crRNA) and cleaves the double-stranded DNA target complementary to the crRNA guide. The two Cpf1 orthologs from Acidaminococcus sp. (AsCpf1) and Lachnospiraceae bacterium (LbCpf1) have been harnessed for eukaryotic genome editing. Cpf1 requires a specific nucleotide sequence, called a protospacer adjacent motif (PAM), for target recognition. Besides the canonical TTTV PAM, Cpf1 recognizes suboptimal C-containing PAMs. Here, we report four crystal structures of LbCpf1 in complex with the crRNA and its target DNA containing either TTTA, TCTA, TCCA, or CCCA as the PAM. These structures revealed that, depending on the PAM sequences, LbCpf1 undergoes conformational changes to form altered interactions with the PAM-containing DNA duplexes, thereby achieving the relaxed PAM recognition. Collectively, the present structures advance our mechanistic understanding of the PAM-dependent, crRNA-guided DNA cleavage by the Cpf1 family nucleases.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Contexto em Saúde:
3_ND
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
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DNA
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RNA Guia de Cinetoplastídeos
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Endonucleases
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Proteínas Associadas a CRISPR
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Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas
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Sistemas CRISPR-Cas
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Ácidos Nucleicos Heteroduplexes
Limite:
Humans
Idioma:
En
Revista:
Mol Cell
Ano de publicação:
2017
Tipo de documento:
Article