Figure 4
From: De novo DNA methylation during monkey pre-implantation embryogenesis
Tracing of gamete-specific hypermethylated CpG sites and X chromosome inactivation during early embryogenesis. Box plot of methylation levels at sperm-specific hypermethylated sites (methylation level > 0.75 in sperm and < 0.25 in oocytes, n = 2365) (A) and at oocyte-specific hypermethylated sites (methylation level > 0.75 in oocytes and < 0.25 in sperm, n = 5 356) (B) during early pre-implantation development. The average methylation level is indicated by the dashed line. (C) Heatmap of DNA methylation dynamics in sperm-specific hypermethylated promoters and oocyte-specific hypermethylated promoters during pre-implantation embryogenesis. GO analysis indicates that genes with oocyte-specific hypomethylated promoters are enriched in the citrate cycle pathway, the pyruvate metabolism pathway, and cell connections, whereas genes with sperm-specific hypomethylated promoters are enriched in negative regulation of the Wnt signaling pathway and DNA replication (GO terms with P-value < 0.05). (D) RT-qPCR analysis of xist expression during early embryogenesis relative to the expression of gapdh (encoding glyceraldehyde phosphate dehydrogenase) (n = 3 per stage). (E) Methylation levels of maternal-specific and paternal-specific X chromosome CpG sites during early embryogenesis. (F) Graphical representation of DMR distribution in a representative genomic region of X chromosome. (G) Dynamics of the methylation level on X chromosome follows a similar pattern to the global methylation.
