Zinc-finger transcription factors are associated with guanine quadruplex motifs in human, chimpanzee, mouse and rat promoters genome-wide

Nucleic Acids Res. 2011 Oct;39(18):8005-16. doi: 10.1093/nar/gkr536. Epub 2011 Jul 4.

Abstract

Function of non-B DNA structures are poorly understood though several bioinformatics studies predict role of the G-quadruplex DNA structure in transcription. Earlier, using transcriptome profiling we found evidence of widespread G-quadruplex-mediated gene regulation. Herein, we asked whether potential G-quadruplex (PG4) motifs associate with transcription factors (TF). This was analyzed using 220 position weight matrices [designated as transcription factor binding sites (TFBS)], representing 187 unique TF, in >75,000 genes in human, chimpanzee, mouse and rat. Results show binding sites of nine TFs, including that of AP-2, SP1, MAZ and VDR, occurred significantly within 100 bases of the PG4 motif (P < 1.24E-10). PG4-TFBS combinations were conserved in 'orthologously' related promoters across all four organisms and were associated with >850 genes in each genome. Remarkably, seven of the nine TFs were zinc-finger binding proteins indicating a novel characteristic of PG4 motifs. To test these findings, transcriptome profiles from human cell lines treated with G-quadruplex-specific molecules were used; 66 genes were significantly differentially expressed across both cell-types, which also harbored conserved PG4 motifs along with one/more of the nine TFBS. In addition, genes regulated by PG4-TFBS combinations were found to be co-regulated in human tissues, further emphasizing the regulatory significance of the associations.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • Binding Sites
  • Chromatin Immunoprecipitation
  • Conserved Sequence
  • G-Quadruplexes*
  • Gene Expression Profiling
  • Gene Expression Regulation
  • Genome
  • Guanine / analysis
  • Humans
  • Mice
  • Nucleotide Motifs
  • Pan troglodytes / genetics
  • Promoter Regions, Genetic*
  • Rats
  • Transcription Factors / metabolism*
  • Zinc Fingers*

Substances

  • Transcription Factors
  • Guanine