ATAC-seq of IVF porcine embryos: GV oocytes
ATAC-seq libraries of porcine embryos were prepared by TruePrep DNA Library Prep Kit V2 (Vazyme, TD502). 50 oocytes or embryos were harvested each group. Zona-free oocytes or embryos were lysed in 6 L lysis buffer (10 mM Tris-HCl pH 7.5, 10 mM NaCl, 3 mM MgCl2, 0.5% NP-40) on ice for 10 minutes. Subsequently, 4 L H2O, 4 L 5X TTBL, and 5 L TTE mix V5 were added, followed by incubation at 37C for 30 minutes to perform tagmentation. The reaction was terminated with 5 L 5X TS. DNA was extracted using 100 L phenol chloroform-isoamyl alcohol (25:24:1). Libraries were constructed by amplifying extracted DNA with 0.5 L primers (primer 1: 5-TCGTCGGCAGCGTCAGATGTGTATAAGAGACAG-3, primer 2: 5-GTCTCGTGGGCTCGGAGATGTGTATAAGAGACAG-3), 5 L indexes (Vazyme, TD202), and 25 L High-Fidelity DNA Polymerase (NEB, M0541S). Amplified libraries were purified using VAHTS DNA Clean Beads and sequenced on the Illumina NovaSeq 6000 platform with 150 bp paired-end reads.