Figure 5

Circular dichroism measurements and native gel electrophoreses of PQSs from LINE-1, HERV and Alu elements. (a) CD spectra of the oligonucleotides (shown in Table S1) obtained at various concentrations of potassium and at various temperatures are marked by different colors. The peak at 265 nm indicates formation of the parallel-stranded quadruplex while maximum at 295 nm corresponds to an antiparallel-stranded quadruplex. Sketches correspond to the most probable folding of the dominating quadruplex structure according to CD and electrophoretic results. (b) Native gel electrophoreses of LINE-1, HERV and Alu PQS in the presence of 150 mM KCl at 20°C or 1°C.