Figure 3.

Cations modulate the affinity of hydrophobically modified DNA to liquid-phase PC bilayers. (a) A sketch illustrating the designed library of DNA constructs varying in nt:chol ratio (details of the designs can be found in Section S1, while the oligonucleotides’ sequences can be found in Table S1). (b) Fluorescence–intensity distributions of the Cy3-labeled 2C DNA constructs as recorded on the surface of POPC GUVs at varying Mg²⁺ concentration and representative confocal micrographs. Scale bars: 5 μm. The top image is recorded in the absence of magnesium, where no DNA accumulation on the GUVs was detected. Scale bar: 20 μm. The contrast of the top image was increased for clarity, while no contrast adjustments are applied to the micrographs below it. (c) Magnesium dependency of the peak of the intensity distributions in panel (b) along with analogous data recorded with 1C and ss1C structures (Figure S18 and Table S3). The bar plot in the inset shows the differences in the ratio between the number of nucleotides and cholesterol tags. The solid lines are best fits to a Hill function, used only for illustrating the observed trend (Section S3 and Table S2).