Figure 5.

CD spectra of 5 × 10⁻⁶ M [TA-core], [A-core-TT] and [core-T] constructs mixed with 40% PEG at different temperatures and incubated for various periods of time. In studies employing synthetic polymers as MC mimetics, re-annealing of DNA constructs in the presence of MC agents is typically used to accelerate the MC promoted DNA refolding. However, re-annealing of DNA constructs in X. laevis egg extracts cannot be performed as it would lead to thermal denaturation of proteins that are dominant contributing factors to the native MC environment. Here, we show that the CD spectra of telomeric constructs incubated in the presence of PEG for 2 h at 37°C are essentially the same as those obtained for the telomeric constructs re-annealed in the presence of PEG (cf. Figure 2D–F). To avoid any bias from differences in sample preparations, the telomeric repeat constructs were incubated in X. laevis egg extract and 40% PEG 200 for 2 h at 37°C prior to acquisition of NMR spectra (see Figure 6).