Figure 3. ISW1a remodeling is blocked by a bound Gal4DBD.
Nucleosomes were remodeled by 1 nM ISW1a with 1 mM ATP for 10 min with or without Gal4DBD. Shaded regions indicate locations of Gal4 binding sequence and 601NPE. (A) Distributions of the locations of the nucleosome and bound Gal4DBD, either before remodeling or without Gal4DBD, as controls. (B) Distributions of the locations of the nucleosome after ISW1a remodeling in the presence of Gal4DBD on three different templates of increasing separation between the Gal4 binding sequence and the 601NPE. For each template, the nucleosome position distribution is dominated by a narrow population, but has a few outliers which were moved a much greater distance and some of which even passed the Gal4 binding sequence. These outliers (∼5%) were likely a result of templates that did not have a bound Gal4DBD initially (∼5%; see main text). This is further supported by the observation that none of these outlier traces revealed a bound Gal4DBD. Nonetheless, in order to avoid possible bias, these nucleosome positions were still used for further analysis in (C) and thus contributed to the error bars in (C). (C) Relationship between the distance the remodeled nucleosome moved and the separation between the Gal4 binding sequence and the 601NPE. Error bars are SEM.
Figure 3—figure supplement 1. Single molecule unzipping simultaneously detects Gal4DBD and an end-positioned nucleosome.
Figure 3—figure supplement 2. ISW1a centers a nucleosome between a bound Gal4DBD and the template end.
