title: GSM2878134: f03_E14.5_GF_UD_rep3; Mus musculus; ATAC-seq
library_construction_protocol: Sorted cells were resuspended in Lysis buffer (10mM Tris-HCl pH 7.4, 10mM MgCl2, 0.1% IGEPAL CA-630) and underwent Transposase reaction with Tn5 For library amplification, two sequential 9-cycle PCR were performed in order to enrich small tagmented DNA fragments. 2μl of indexing primers included in the Nextera Index kit and KAPA HiFi  HotStart ready mix were used, then after the first PCR, the libraries were selected for small fragments (less than 600 bp) using SPRI cleanup. A second PCR was performed with the same conditions in order to obtain the final library. DNA concentration was  measured with a Qubit fluorometer (Life Technologies) and library sizes were determined using TapeStation (Agilent Technologies). Libraries where sequenced on a NextSeq for an average of 10 million unique reads per sample.