G-quadruplex Structures Contribute to Differential Radiosensitivity of the Human Genome.
iScience
; 21: 288-307, 2019 Nov 22.
Article
em En
| MEDLINE
| ID: mdl-31678912
ABSTRACT
DNA, the fundamental unit of human cell, generally exists in Watson-Crick base-paired B-DNA form. Often, DNA folds into non-B forms, such as four-stranded G-quadruplexes. It is generally believed that ionizing radiation (IR) induces DNA strand-breaks in a random manner. Here, we show that regions of DNA enriched in G-quadruplex structures are less sensitive to IR compared with B-DNA in vitro and inside cells. Planar G-quartet of G4-DNA is shielded from IR-induced free radicals, unlike single- and double-stranded DNA. Whole-genome sequence analysis and real-time PCR reveal that genomic regions abundant in G4-DNA are protected from radiation-induced breaks and can be modulated by G4 stabilizers. Thus, our results reveal that formation of G4 structures contribute toward differential radiosensitivity of the human genome.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
IScience
Ano de publicação:
2019
Tipo de documento:
Article