title: pachytene spermatocytes, whole cell extract
design: Pachytene spermatocytes and round spermatids were isolated from whole testes in adult CD1 wild type male mice by sedimentation at unit gravity using the STA-PUT apparatus.  Chromatin immunoprecipitation was done using 1x107 pachytene spermatocytes (4C DNA content) and 4x107 round spermatids (1C DNA content) per experiment as described in Lee et al, Nat Protoc 2006. Sequencing libraries were prepared using the ChIP-Seq Sample Prep Kit (Illumina, 1003473) according to the manufacturer’s instructions.