Chromatin States in Mouse Sperm Correlate with Embryonic and Adult Regulatory Landscapes

Abstract

The mammalian sperm genome is thought to lack substantial information for the regulation of future expression after fertilization. Here, we show that most promoters in mouse sperm are flanked by well-positioned nucleosomes marked by active histone modifications. Analysis of these modifications suggests that many enhancers and super-enhancers functional in embryonic and adult tissues are already specified in sperm. The sperm genome is bound by CTCF and cohesin at sites that are also present in round spermatids and embryonic stem cells (ESCs). These sites mediate interactions that organize the sperm genome into domains and compartments that overlap extensively with those found in mESCs. These results suggest that sperm carry a rich source of regulatory information, encoded in part by its three-dimensional folding specified by CTCF and cohesin. This information may contribute to future expression during embryonic and adult life, suggesting mechanisms by which environmental effects on the paternal germline are transmitted transgenerationally.

Keywords

• chromatin
• transcription
• CTCF
• TAD
• pluripotency
• stem cell