Extended Data Figure 4.

a, example micrographs and complete sets of reference free class averages of the helicase activation reactions indicated, washed with high salt wash buffer (buffer A + KCl). –DDK, +Mcm10, 7410 of 23092 total particles were DH. +DDK, +Mcm10, of 43320 total particles, 14668 and 10492 were CMG and DH respectively. +DDK, –Mcm10, of 12920 total particles, 3984 and 2226 were CMG and DH respectively. Classes are positioned with respect to the abundance of source particles, with the most abundant class in the top left-hand corner, and abundance decreasing from left to right and top to bottom. b, as in a. with representative source micrographs. 5032/6815 and 2049/20904 particles were DH when Dpb11 or Sld3/7 were omitted respectively. Scale bar represents 100 nm. c, comparison of CMG formed under the conditions indicated. HSW is buffer A + KCl, LSW is buffer A + 0.25 M K-glutamate. d, as in Figure 4d. e, as in Figure 4e. Arrows mark position of CMG. f, representative crops from micrographs imaging the samples indicated. MCM trains are marked with arrows. Trains were not observed when Mcm10 or the protein road block was omitted. Scale bar is 100 nm.