Fig. 5.

Cross-linking inhibits remodeling-dependent nucleosome mobilization to a position off the end of the DNA fragment. (A) Nucleosomes were reconstituted on the 343-bp 601 DNA fragment with H2A G2C, and un-cross-linked and cross-linked nucleosomes (0.5 nM) were remodeled with 3 nM SWI/SNF. Reactions were stopped at various times by addition of competitor DNA, and products were analyzed on nondenaturing 4% polyacrylamide translational gels. Assigned translational positions relative to the DNA are shown on the right of the gels. (B) As in panel A except that remodeling was carried out with 0.1 nM RSC complex. (C and D) The bands corresponding to the original centrally located nucleosomes in panels A and B, respectively, were quantified and plotted versus remodeling time. (E) Remodeling of un-cross-linked and cross-linked nucleosomes containing H2A G2C with saturating RSC. Reaction mixtures containing 0.5 nM RSC were incubated at 30°C for 5 min, and the remodeling reactions were initiated by addition of 0.8 μM ATP. Reactions were stopped at the indicated times, and samples were analyzed as described for panel A.