Molecular mechanism for Tn7-like transposon recruitment by a type I-B CRISPR effector.
Cell
; 186(19): 4204-4215.e19, 2023 09 14.
Article
en En
| MEDLINE
| ID: mdl-37557170
ABSTRACT
Tn7-like transposons have co-opted CRISPR-Cas systems to facilitate the movement of their own DNA. These CRISPR-associated transposons (CASTs) are promising tools for programmable gene knockin. A key feature of CASTs is their ability to recruit Tn7-like transposons to nuclease-deficient CRISPR effectors. However, how Tn7-like transposons are recruited by diverse CRISPR effectors remains poorly understood. Here, we present the cryo-EM structure of a recruitment complex comprising the Cascade complex, TniQ, TnsC, and the target DNA in the type I-B CAST from Peltigera membranacea cyanobiont 210A. Target DNA recognition by Cascade induces conformational changes in Cas6 and primes TniQ recruitment through its C-terminal domain. The N-terminal domain of TniQ is bound to the seam region of the TnsC spiral heptamer. Our findings provide insights into the diverse mechanisms for the recruitment of Tn7-like transposons to CRISPR effectors and will aid in the development of CASTs as gene knockin tools.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Ascomicetos
/
Elementos Transponibles de ADN
/
Técnicas de Sustitución del Gen
/
Proteínas Asociadas a CRISPR
/
Sistemas CRISPR-Cas
Idioma:
En
Revista:
Cell
Año:
2023
Tipo del documento:
Article
País de afiliación:
Estados Unidos