GSM7043021: CAST-seq on sample treated with two RNPs  [UNC-u1d4-2]; Mus musculus; OTHER
Genomic DNA was isolated from cells using theNucleoSpin Tissue Mini kit for DNA from cells and tissue (Macherey-Nagel) according to the manufacturer's instructions. Library construction was essentially performed as described by Turchiano et. al (Cell Stem Cell, 2021). Briefly, gDNA was fragmented by enzymatic digestion using the NEBNext® Ultra™ II FS DNA Library Prep (NEB) to obtain average fragment lengths of 200-350 bp. The DNA was end repaired and a protruding 3'-A nucleotide was added according to the manufacturer's instructions  in order to enable the ligation of a linker sequence with a protruding 3'-T. After linker ligation, fragments were purified using the QIAquick PCR Purification Kit (NEB). The region of interes (on-target site) was amplified in two rounds of PCR using Q5® Hot Start High-Fidelity DNA Polymerase (NEB). PCR conditions were: 20 cycles at 95°C for 15 s, 63°C (first reaction) or 68°C (second reaction) for 20 s, 72°C for 20 s. The first reaction was performed with primers complementary to the linker sequence and to a sequence in close proximity to the on-target site (bait primer). Two decoy primers were introduced to reduce full-length amplification of the fragments which contain the on-target sequence without a chromosomal aberration event. The second PCR utilized nested primers to reduce the amount of mis-amplified fragments and to introduce a binding platform for barcoding primers. DNA fragments from the second PCR were purified using the QIAquick® PCR purification kit (Qiagen) and barcoded. Third PCR introduced the barcoded Illumina adapter for sequencing (NEBNext® Multiplex Oligos for Illumina; Index Primers Sets 1-4). Sequencing was outsourced to service NGS provider Genewiz (part of Azenta Life Sciences) on where it was performed on a Illumina HiSeq4000 device collecting 2x150 bp paired-end reads.