DNA packaging of Murine spermatozoal chromatin

During mammalian spermiogenesis, the majority of the nucleosomes packaging the male haploid genome are replaced by protamines to produce a highly compact chromatin architecture that is critical to male fertility. We have carried out a genomewide survey of murine spermatozoal chromatin using a micrococal nuclease approach to characterise the DNA sequences that remain packaged by histones. Limited digestion with micrococcal nuclease facilitates the release of a nucleosome-rich chromatin from mature spermatozoa. Whole genome CGH arrays were used to map the histone and protamine bound portions of spermatozoal DNA.