G4 motifs are greatly enriched near promoters, suggesting that quadruplex structures may be targets of transcriptional regulation. Here we show, by ChIP-Seq analysis of human cells, that 40% of the binding sites of the transcription-associated helicases, XPB and XPD, overlap with G4 motifs. Th...
In addition, the potential for quadruplex formation is higher within oncogenes as compared to tumor suppressor genes [80]. Computational analyses showed significant enrichment of G-quadruplex-forming sequences in the promoter regions of human genes near transcription start sites (TSS) [81]. The ...