G-quadruplex structures: in vivo evidence and function

Trends Cell Biol. 2009 Aug;19(8):414-22. doi: 10.1016/j.tcb.2009.05.002. Epub 2009 Jul 7.


Although many biochemical and structural studies have demonstrated that DNA sequences containing runs of adjacent guanines spontaneously fold into G-quadruplex DNA structures in vitro, only recently has evidence started to accumulate for their presence and function in vivo. Genome-wide analyses have revealed that functional genomic regions from highly divergent organisms are enriched in DNA sequences with G-quadruplex-forming potential, suggesting that G-quadruplexes could provide a nucleic-acid-based mechanism for regulating telomere maintenance, as well as transcription, replication and translation. Here, we review recent studies aimed at uncovering the in vivo presence and function of G-quadruplexes in genomes and RNA, with a particular focus on telomeric G-quadruplexes and how their formation and resolution is regulated to permit telomere synthesis.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Base Sequence
  • DNA / chemistry*
  • DNA / genetics
  • DNA / metabolism*
  • G-Quadruplexes*
  • Humans
  • RNA / chemistry
  • RNA / genetics
  • RNA / metabolism
  • Telomere / chemistry
  • Telomere / genetics
  • Telomere / metabolism


  • RNA
  • DNA