A Sequence-Dependent DNA Condensation Induced by Prion Protein

Figure 8

Quantification of the dissociation of YOYO from DNA during its condensation by the prion protein. (a) A 500 μl solution containing YOYO-1 bound to gcDNA (DNA-phosphate 1 μM; dye to DNA 1 : 50) yields the spectrum (1). The addition of 38 μl of stock α-PrP (40 μM) to the solution (final protein concentration 3 μM) after 1 hr incubation yields the spectrum (2). Following this, 4 μl gcDNA having 150 μM phosphate concentration was further added to the solution resulting in 1 μM free DNA concentration which yielded the spectrum (3). (b) Control experiment. Spectrum (1) is YOYO bound gcDNA as in (a); (2) and (3), respectively, are the spectra after the addition of 38 μl buffer (instead of protein as in (a)) followed by the addition of gcDNA having 1 μM final DNA concentration.

(a) α-PrP

(b) Buffer