Fig. 6: ORC-mediated MCM loading occurs at nucleosomal sites.

a Cartoon illustrating the experimental assay that evaluates MCM loading at nucleosomal sites via high-salt wash. b A representative kymograph showing that MCM complexes (red) formed on a DNA tether in the presence of unlabeled ORC, Cdc6 and Cdt1. Upon moving to a high-salt buffer (0.5 M NaCl), a fraction of the MCMs displayed diffusive behavior without dissociation, demonstrating their successful loading onto DNA. MCM diffusion could occur from both bare DNA and nucleosome sites (white arrowheads in the zoomed-in view). Blue arrowheads indicate nucleosome positions, all of which were at non-ARS1 sites in this example. MCM and nucleosome fluorescence signals are also separately shown in gray scale at the bottom. c Fraction of nucleosome-colocalized MCM complexes that underwent diffusion without dissociation (red), remained stably bound to the nucleosome (black), or dissociated into solution (white) upon high-salt wash. n indicates the number of MCM complexes analyzed. Source data are provided as a Source Data file.