Selective recognition of oncogene promoter G-quadruplexes by Mg2+.
Biochem Biophys Res Commun
; 402(4): 614-8, 2010 Nov 26.
Article
em En
| MEDLINE
| ID: mdl-20971074
ABSTRACT
Mg(2+) is one of the most important cations in cells, affecting the structures and functions of the proteins and nucleic acids. It should be noted that Mg(2+) is indispensable in DNA transcription, where G-quadruplex is believed to be actively involved. Therefore, it is important to investigate the influence of Mg(2+) on G-quadruplex. Here we studied the effect of Mg(2+) on G-quadruplex DNA with CD, FRET, EMSA, and PCR-stop assay. We found that various G-quadruplexes could be differentiated through simultaneous addition of both K(+) and Mg(2+), which could be used for selective identification of G-quadruplexes in promoter oncogene but not in telomere. Mg(2+) at physiological relevant concentration not only greatly enhanced the thermostability of oncogene G-quadruplexes but also efficiently protected them from unfolding by their complementary strands, which revealed the great impact of Mg(2+) on the equilibrium between promoter G-quadruplex and duplex DNA. The PCR-stop assay further confirmed that Mg(2+) could affect gene transcription by stabilizing promoter G-quadruplex. The above studies were carried out for various G-quadruplexes of varying sequences in promoter oncogenes and telomeric region. Our results suggest that Mg(2+) may be a key regulator for G-quadruplexes of oncogene promoter, which can subsequently affect the expression of related genes.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oncogenes
/
Regulação Neoplásica da Expressão Gênica
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Regiões Promotoras Genéticas
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Quadruplex G
/
Magnésio
Limite:
Humans
Idioma:
En
Ano de publicação:
2010
Tipo de documento:
Article