DETECTION OF NUCLEIC ACIDS USING G-QUARTETS

摘要

Oligonucleotides which form G-quartet structures have been found to be usefu l influorescence assays to detect a selected nucleic aci d sequence. When one end of the oligonucleotide is labeled with a donor fluorophore and the other end is lab eled with an acceptor dye, the folding of the molecule in the G-quartet structure brings the donor-acceptor pair into close proximity, allowing an interaction between the two labels wh ich results in quenching of donor fluorescence or a change in other fluorescence properties which are the result of the interaction of two dyes in close proximity. The G-quartet stru cture unfolds upon hybridization to its complementary sequence, increasing the distance between the two dye labels. This results in decreased donor quenching or a change in another pro ximity-related fluorescence parameter. The associated increase in donor fluorescence intens ity or the change in another fluorescence parameter may be monitored as an indication of the p resence of a selected nucleic acid sequence. Alternatively, in some cases a decrease in a cceptor fluorescence may be monitored as an indication of the presence of the select ed nucleic acid sequence when the acceptor is also a fluorophore.