Uniformity of Nucleosome Preservation Pattern in Mammalian Sperm and Its Connection to Repetitive DNA Elements

• DOI: 10.1016/j.devcel.2014.05.023
• Publication Date: 2014-07-03T16:01:44Z
• Authors: Birgit Samans; Yang Yang; Stefan Krebs; Gaurav Vilas Sarode; Helmut Blum; Myriam Reichenbach; Eckhard Wolf; Klaus Steger; Temuujin Dansranj...; Undraga Schagdars...
• Keywords: Male; 0303 health sciences; Genome, Human; DNA; Chromatin Assembly and Disassembly; Spermatozoa; Nucleosomes; 03 medical and health sciences; Gene Expression Regulation; Animals; Humans; Cattle; Promoter Regions, Genetic; Developmental Biology; Repetitive Sequences, Nucleic Acid; Transcription Factors

Nucleosome-to-protamine exchange during mammalian spermiogenesis is essential for compaction and protection of paternal DNA. It is interesting that, depending on the species, 1% to 15% of nucleosomes are retained, but the generalizability and biological function of this retention are unknown. Here, we show concordantly in human and bovine that nucleosomes remained in sperm chromatin predominantly within distal intergenic regions and introns and associated with centromere repeats and retrotransposons (LINE1 and SINEs). In contrast, nucleosome depletion concerned particularly exons, 5'-UTR, 3'-UTR, TSS, and TTS and was associated with simple and low-complexity repeats. Overlap of human and bovine genes exhibiting nucleosome preservation in the promoter and gene body revealed a significant enrichment of signal transduction and RNA- and protein-processing factors. Our study demonstrates the genome-wide uniformity of the nucleosome preservation pattern in mammalian sperm and its connection to repetitive DNA elements and suggests a function in preimplantation processes for paternally derived nucleosomes.