MI oocyte, Young, rep2
Fully grown oocytes were isolated from the ovaries 48 hours after injection of pregnant mares serum gonadotropin (Serotropin, ASKA Animal Health) into female mice, and cultured in M2 medium containing 3-isobutyl-1-metyl-xanthine (IBMX, Sigma). The oocytes were released from IBMX by washing to induce meiotic resumption. Ten MI oocytes per replicate were sampled into a tube containing the lysis buffer, frozen with liquid nitrogen. Chromatin was digested with MNase. Libraries were prepared with NEBnext Ultra II DNA Library Prep Kit (NEB).