Fig. 3: Mobility of rapidly bound ORCJF646 on 10.4 kbp DNA containing an ARS1 (or mutated) origin (chromatinized or not).

Dataset acquired as described in Fig. 2a. a Traces collected on DNA containing a chromatinized origin illustrating motion of ORCJF646: (i) initially localized within the bin containing the chromatinized origin or (ii) initially localized elsewhere. b Histograms of the diffusion constants of ORCJF646 on DNA molecules containing (i) a non-chromatinized origin, (ii) a chromatinized origin, (iii) a non-chromatinized mutated origin, and (iv) a chromatinized mutated origin. Only foci containing 1 or 2 ORCJF646 are included in the analysis (Nfoci). Data are presented as mean values ± one-sigma Wilson confidence intervals. The observed bimodal distribution is fitted to a double log-normal function (solid black line) which identifies a slow ORC population (55% of the distribution with 0.0049± 0.0028 kbp2/s, mean ± SEM) and a fast ORC population (0.152 ± 0.023 kbp2/s, mean ± SEM). The dashed line indicates the average of the means of the two normal distributions used to fit log10(D); this average is used as a threshold (D*). The means of these subpopulations are imposed in the fits to the data in (ii–iv). Created with BioRender.com. c Examination of the slow ORC population. (i) Fitted proportion of the slow ORC population for the datasets in (b-i)-(b-iv), as indicated by the corresponding color bar (ARS1: non-mutated origin; Mut ori: mutated origin; nuc: chromatinized). (ii) The population of ORC initially localized within the bin containing the (chromatinized or not) origin was extracted from the dataset; the fraction of this population that is slow (D < D*) is shown here. (iii) The population of ORC initially localized outside the bin containing the (chromatinized or not) origin was extracted from the dataset; the fraction of this population that is slow (D < D*) is shown here. Nfoci-ARS1 = 69; Nfoci-ARS1+nuc = 35; Nfoci-Mut ori = 40; Nfoci-Mut ori+nuc = 27. Data are presented as mean values ± one-sigma Wilson confidence intervals. Statistical significance is determined by a two-sided binomial test: n. s. not significant, * p < 0.05, ** p < 0.005, **** p < 0.00005, ***** p < 0.000005 ****** p < 0.0000005. Source data are provided as a Source Data file.