Formation of DNA:RNA hybrid G-quadruplexes of two G-quartet layers in transcription: expansion of the prevalence and diversity of G-quadruplexes in genomes.
Angew Chem Int Ed Engl
; 53(48): 13110-4, 2014 Nov 24.
Article
em En
| MEDLINE
| ID: mdl-25267250
ABSTRACT
G-quadruplexes are implicated in important cellular processes. Previous studies mostly focused on intramolecular G-quadruplexes of three or more G-quartets. Those composed of two G-quartets were only shown to form in single-stranded oligonucleotides. On the basis of electrophoresis, DMS footprinting, fluorescence labeling, and photo-cross-linking, we detected the formation of DNARNA hybrid G-quadruplexes (HQs) of two G-quartets during the transcription of DNA duplexes. These HQs have a lifetime on the minute scale and are stabilized by a stabilizing ligand. They are far shorter-lived than the HQs of three G-quartets, which last for hours. The occurrence of putative formation motifs of such HQs shows a transcription-dependent strand-biased selection, thus supporting their formation and function in genomes. They are present in almost all human genes in large amounts. We speculate that the two-G-quartet HQs may be a distinct type of G-quadruplexes that may play a role in timely responsive processes and for purposes of fine-tuning.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oligonucleotídeos
/
DNA
/
RNA
/
Genoma
/
Quadruplex G
Tipo de estudo:
Prevalence_studies
/
Risk_factors_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article