Fig. 4: TOP2α DNA braid resolution is processive.

a Schematic of single and four braided, right- and left-handed DNA braids. b Mean resolution probability by TOP2α-AF555 of right- and left-handed substrate, and right-handed, four braided substrate with 50 μM etoposide. Data modelled as a Bernoulli process, with 5-minute sampling time. Number of resolution events out of total number of technical replicates is indicated above each condition, error bars indicate one standard error. Source data are provided as a Source Data file. c Example image of failed resolution by TOP2α-AF555 in the presence of 50 μM etoposide on a four right-handed, braided substrate. d, e Force vs time curve of four braid resolution, occurring in one or two bursts, respectively, with corresponding scan images and slice through the TOP2α-AF555 intensity. Grey bar in (e) indicates resolution occurring during confocal scan. Further explanation of intensity analysis is provided in Supplementary Fig. 4h. Representative kymographs shown for (d), the one-step transition was observed in 9 independent events (total N = 15), for (e), the two-step transition was observed in 3 independent events (total N = 15). f Histograms of fluorescence intensities of Gaussian fit of four-braid, right-handed substrates. Source data are provided as a Source Data file. g Resolution time of single right- and left- handed braids after entering the protein channel. N refers to the number of molecules tested in different technical replicates. Box plot whiskers represent the full data range (minimum to maximum), boxes indicate the interquartile range (25th to 75th percentiles), and the central line marks the median. Source data are provided as a Source Data file. h Example images before and after resolution of left-handed, four braid. i Histograms of fluorescence intensities of Gaussian fit of four-braid, left-handed substrates Scale bar is 4 μm in all cases. Source data are provided as a Source Data file.