Extended Data Figure 3. Rec114 chromatin binding in the zip3 mutant.

a, Genome-average Rec114 levels. Dashed line represents an independent wild-type profile from Fig. 1d.

b, Effects of zip3 mutation on absolute Rec114 ChIP densities. ChIP-seq coverage was calibrated by qPCR. Each point is the mean for a single chromosome. At 2 h, which is very early in the initial accumulation phase of Rec114 on chromatin, the zip3 mutant has ~;two-fold less Rec114 signal, affecting all chromosomes equivalently. It is possible that this decrease reflects a role for Zip3 early, but since Zip3 is not known to have any function this early in prophase, a more likely explanation is that the zip3 mutant culture lagged slightly behind the wild-type culture. At 4 h, Rec114 ChIP densities were very similar between the cultures, again with little or no difference between chromosomes. However, at 6 h, the zip3 mutant retained substantially more Rec114 signal. At least some of this increase may be attributable to delayed meiotic progression because of inhibition of Ndt80^7,16, but importantly for purposes of this experiment, the Rec114 levels were disproportionately elevated on the 13 larger chromosomes. n = 1 time course for each strain.

c, Per-chromosome profiles of absolute Rec114 ChIP density.

d, Per-chromosome Rec114 ChIP density. This is the intermediate time point for the samples shown in Fig. 1h.