Interaction of human DNA topoisomerase I with G-quartet structures.
Nucleic Acids Res
; 28(24): 4832-8, 2000 Dec 15.
Article
em En
| MEDLINE
| ID: mdl-11121473
ABSTRACT
Because of their role in the control of the topological state of DNA, topoisomerases are ubiquitous and vital enzymes, which participate in nearly all events related to DNA metabolism including replication and transcription. We show here that human topoisomerase I (Topo I) plays an unexpected role of 'molecular matchmaker' for G-quartet formation. G-quadruplexes are multi-stranded structures held together by square planes of four guanines ('G-quartets') interacting by forming Hoogsteen hydrogen bonds. Topo I is able to promote the formation of four-stranded intermolecular DNA structures when added to single-stranded DNA containing a stretch of at least five guanines. We provide evidence that these complexes are parallel G-quartet structures, mediated by tetrads of hydrogen-bonded guanine. In addition, Topo I binds specifically to pre-formed parallel and anti-parallel G4-DNA.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
DNA
/
DNA Topoisomerases Tipo I
/
Guanina
/
Conformação de Ácido Nucleico
Limite:
Humans
Idioma:
En
Revista:
Nucleic Acids Res
Ano de publicação:
2000
Tipo de documento:
Article
País de afiliação:
França