title: ATAC-seq of Bos taurus: mammary gland from cow 0907 at peak lactation
design: ATAC-seq library prepared from Bos taurus mammary gland (peak lactation/late lactation). Nuclear extraction was performed using the method described in 'ATAC-seq: A Method for Assaying Chromatin Accessibility Genome-Wide' for cell samples, and the protocol from 'An improved ATAC-seq protocol reduces background and enables interrogation of frozen tissues' was followed for frozen tissue samples. Transposition was carried out using 40,000 nuclei with Tn5 transposase (Illumina), followed by DNA fragment purification using MinElute PCR Purification Kit (Qiagen). PCR amplification was performed using 1X NEBNext High-Fidelity PCR Master Mix (New England Biolabs), and the amplified product was purified with MinElute PCR Purification Kit (Qiagen). Sequencing was performed on Illumina NovaSeq 6000 with a PE150 strategy.