Title:Recent Development of G-Quadruplex Probes for Cellular Imaging
Volume: 15
Issue: 19
Author(s): Dik-Lung Ma, Modi Wang, Sheng Lin, Quan-Bin Han and Chung-Hang Leung
Affiliation:
Keywords:
Cell imaging, G-quadruplex, Probe, DNA.
Abstract: The G-quadruplex structure is a non-canonical secondary DNA motif that is built from planar
tetrads of guanine residues stabilized by Hoogsteen-type hydrogen bonding. Bioinformatics studies
indicate that sequences rich in guanine that are able to form G-quadruplexes are widely distributed
throughout the human genome, particularly in telomere and promoter regions of genes. G-quadruplex
sequences found in the promoters of human oncogenes, such as k-ras, c-myc and bcl-2 have attracted
particular attention as molecular targets for therapeutic intervention due to their potential capability to regulate gene expression
at the transcriptional level. Moreover, the G-quadruplex structure has been associated with a number of human
diseases arising from defective telomeric maintenance. Despite intensive research in this area, however, the actual function
of G-quadruplexes in vivo has not yet been fully understood. Therefore, significant efforts have been devoted to the
discovery of specific probes for visualizing and distinguishing G-quadruplex structures from other nucleic acid molecules
likely to be found in biological environments. This review summarizes recent studies in the development of G-quadruplex
probes over the past three years, with a particular emphasize on the detection and imaging of G-quadruplex structures
within living cells. Furthermore, the detection and biological relevance of RNA G-quadruplexes is discussed.
