TINA stabilized PT demonstrates improved sensitivity and specificity of DNA based clinical diagnostic assays.
Triple helixes are formed when a single-stranded triplex-forming oligonucleotide (TFO) binds to a purine-containing strand of dsDNA through specific major groove interactions.
[2] Generally, the third-strand affinity of a TFO is low, due to the requirement for the formation of pH-sensitive C+–G–C Hoogsteen base triplexes under physiological conditions in the parallel (pyrimidine) binding motif.
Modification of TFOs has been attempted in order to improve their binding affinities to their targets and to lessen restrictions in the dsDNA sequence with the design of new triplex nucleobases.
In such studies, two G quadruplexes forming sequences which exhibit anti-HIV-1 activity on cell lines were modified using locked nucleic acid (LNA) or insertions of TINA.
However, as shown by Paramasivam et al., bulge insertions of (R)-1-O-[4-(1-pyrenylethynyl)phenylmethyl]glycerol (TINA) into TFOs with high guanine concentrations greatly decreases the presence of self-association via potassium.