Fig. 5: Homogeneously methylated sperm histones are maintained during early embryonic replication.

a Experimental setup to monitor the fate of sperm-methylated histone peaks after replication. b Overlap between peaks of H3K4me3 and H3K27me3 before and after replication of sperm chromatin in egg extract. c Boxplots of HMD for all sperm peaks and for peaks that are lost or retained after replication. d Boxplots of the size of all sperm peaks, and of peaks that are lost or retained after replication. Data in c and d are obtained from N. sperm peaks H3K4me3: 36020; N. sperm retained H3K4me3: 27300; N sperm lost H3K4me3: 8715. N. sperm peaks H3K27me3: 55854; N. sperm retained H3K27me3: 13214; N sperm lost H3K27me3: 42635. ***p value < 1e−3 (two-sample Kolmogorov–Smirnov test). e Ratio of fold enrichment of peaks retained after replication over those lost after replication at indicated genomic features. Fold enrichments (observed/random) were obtained from 1000 randomisations and all instances showed an empirical p value < 1e−3. f Overlap between peaks of H3K4me3 in sperm and in blastula embryos. g Boxplots indicating HMD for all sperm peaks and for peaks that are lost or retained in blastula compared with sperm, and lost or retained in blastula compared with replicated sperm. h Boxplots of peak sizes for all sperm peaks and for peaks lost and retained in blastula compared with sperm, and in blastula compared with replicated sperm. In g and h ***p value < 1e−3 and are obtained by the two-sample Kolmogorov–Smirnov test. i Ratio of fold enrichment of peaks retained in blastula versus those in sperm at indicated genomic features. This ratio has been obtained as in e. HMD is from data pooled from two independent replicates. Peaks retention/lost are consensus from three independent replicates.