Top3-Rmi1 dissolve Rad51-mediated D loops by a topoisomerase-based mechanism.
Mol Cell
; 57(4): 595-606, 2015 Feb 19.
Article
em En
| MEDLINE
| ID: mdl-25699708
ABSTRACT
The displacement loop (D loop) is a DNA strand invasion product formed during homologous recombination. Disruption of nascent D loops prevents recombination, and during synthesis-dependent strand annealing (SDSA), disruption of D loops extended by DNA polymerase ensures a non-crossover outcome. The proteins implicated in D loop disruption are DNA motor proteins/helicases that act by moving DNA junctions. Here we report that D loops can also be disrupted by DNA topoisomerase 3 (Top3), and this disruption depends on Top3's catalytic activity. Yeast Top3 specifically disrupts D loops mediated by yeast Rad51/Rad54; protein-free D loops or D loop mediated by bacterial RecA protein or human RAD51/RAD54 resist dissolution. Also, the human Topoisomerase IIIa-RMI1-RMI2 complex is capable of dissolving D loops. Consistent with genetic data, we suggest that the extreme growth defect and hyper-recombination phenotype of Top3-deficient yeast cells is partially a result of unprocessed D loops.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Saccharomyces cerevisiae
/
Proteínas de Ligação a DNA
/
Rad51 Recombinase
/
RecQ Helicases
/
Recombinação Homóloga
/
Modelos Genéticos
Limite:
Humans
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article