G4access identifies G-quadruplexes and their associations with open chromatin and imprinting control regions

Archive ouverte

Esnault, Cyril | Magat, Talha | Aabidine, Amal Zine El | Garcia-Oliver, Encar | Cucchiarini, Anne | Bouchouika, Soumya | Llères, David | Goerke, Lutz | Luo, Yu | Verga, Daniela | Lacroix, Laurent | Feil, Robert | Spicuglia, Salvatore | Mergny, Jean‐louis | Andrau, Jean Christophe

Edité par CCSD ; Nature Publishing Group -

International audience. Metazoan promoters are enriched in secondary DNA structure-forming motifs, such as G-quadruplexes (G4s). Here we describe ‘G4access’, an approach to isolate and sequence G4s associated with open chromatin via nuclease digestion. G4access is antibody- and crosslinking-independent and enriches for computationally predicted G4s (pG4s), most of which are confirmed in vitro. Using G4access in human and mouse cells, we identify cell-type-specific G4 enrichment correlated with nucleosome exclusion and promoter transcription. G4access allows measurement of variations in G4 repertoire usage following G4 ligand treatment, HDAC and G4 helicases inhibitors. Applying G4access to cells from reciprocal hybrid mouse crosses suggests a role for G4s in the control of active imprinting regions. Consistently, we also observed that G4access peaks are unmethylated, while methylation at pG4s correlates with nucleosome repositioning on DNA. Overall, our study provides a new tool for studying G4s in cellular dynamics and highlights their association with open chromatin, transcription and their antagonism to DNA methylation.

Suggestions

Du même auteur

G-quadruplexes are promoter elements controlling nucleosome exclusion and RNA polymerase II pausing

Archive ouverte | Esnault, Cyril | CCSD

Despite their central role in transcription, it has been difficult to define universal sequences associated to eukaryotic promoters. Within chromatin context, recruitment of the transcriptional machinery requires opening of the pr...

Guidelines for G-quadruplexes: I. In vitro characterization

Archive ouverte | Luo, Yu | CCSD

International audience. Besides the well-known DNA double-helix, non-canonical nucleic acid structures regulate crucial bio- logical activities. Among these oddities, guanine-rich DNA sequences can form unusual four...

Analyses of Promoter, Enhancer, and Nucleosome Organization in Mammalian Cells by MNase-Seq

Archive ouverte | Esnault, Cyril | CCSD

International audience

Chargement des enrichissements...