FIGURE 2.
Treating nucleosomes with yNAP-1. In panel a, the FRET efficiency of nucleosome samples is plotted as a function of incubation time with yNAP-1. yNAP-1 was present at ratios of 0.5 mol yNAP-1 dimer per mole of nucleosomes (nucleosome concentration 10 nM). The response of treated 5S (solid squares, solid line), MMTV-B (solid circles, dotted line), or GAL10 (solid triangles, dashed line) nucleosome samples are shown. The response of a sample (GAL10) incubated under the same conditions but without yNAP-1 is also shown (open inverted triangles). 5S and MMTV-B samples also show no FRET efficiency changes in the absence of yNAP-1 (data not shown). The lines are least-square fits (linear or polynomial) to the data points. Panels b and c show salt titrations, plots of FRET efficiency as a function of NaCl concentration, for 5S (panel b) or GAL10 (panel c) samples without yNAP-1 treatment (solid squares, solid lines) or after yNAP-1 treatment as described in panel a (open circles, dashed lines). The lines are simply drawn to connect the points as an aid in visualization. The curve traced out by “x” in panel c is the curve for treated 5S samples (panel b), included again here for ease of comparison of 5S and GAL10 responses.