GSM7096201: GMP_Tet2_Rep1; Mus musculus; ATAC-seq
Cell sorting was performed on FACS Aria II (BD Biosciences). Single stained and Fluorescence Minus One stained cells were used as controls. Samples were incubated with the antibody cocktail in PBS 2% FBS for 30 minutes at 4 degrees before sorting. 7-AAD Viability Staining Solution (BioLegend) was included in the sample preparation for flow cytometry to exclude dead cells. For a detailed description of tagmentation protocols and buffer formulations refer to the SureCell ATAC-Seq Library Prep Kit User Guide (17004620, Bio-Rad). Sorted cells and tagmentation related buffers were chilled on ice. Lysis was performed simultaneously with tagmentation. Washed and pelleted cells were resuspended in Whole Cell Tagmentation Mix containing 0.1% Tween-20, 0.01% Digitonin, 1x PBS supplemented with 0.1% BSA, ATAC Tagmentation Buffer and ATAC Tagmentation Enzyme (ATAC Tagmentation Buffer and Enzyme are both included in the SureCell ATAC-Seq Library Prep Kit (17004620, Bio-Rad)). Cells were mixed and agitated on a ThermoMixer for 30 min at 37°C. Tagmented cells were kept on ice prior to encapsulation. Tagmented cells were loaded onto a ddSEQ Single-Cell Isolator. Single-cell ATAC-seq libraries were prepared using the SureCell ATAC-Seq Library Prep Kit (17004620, Bio-Rad) and SureCell ddSEQ Index Kit (12009360, Bio-Rad). Bead barcoding and sample indexing were performed in a C1000 Touch™ Thermal cycler with a 96-Deep Well Reaction Module: 37°C for 30 min, 85°C for 10 min, 72°C for 5 min, 98°C for 30 sec, 8 cycles of 98°C for 10 sec, 55°C for 30 sec, and 72°C for 60 sec, and a single 72°C extension for 5 min to finish. Emulsions were broken and products cleaned up using Ampure XP beads. Barcoded amplicons were further amplified using a C1000 Touch™ Thermal cycler with a 96-Deep Well Reaction Module: 98°C for 30 sec, 6-9 cycles (cycle number depending on the cell input, Section 4 Table 3 of the User Guide) of 98°C for 10 sec, 55°C for 30 sec, and 72°C for 60 sec, and a single 72°C extension for 5 min to finish. PCR products were purified using Ampure XP beads and quantified on an Agilent Bioanalyzer using the High-Sensitivity DNA kit. Libraries were loaded at 1.5 pM on a NextSeq 550 using the NextSeq High Output Kit and sequencing was performed using the following read protocol: Read 1 118 cycles, i7 index read 8 cycles, and Read 2 40 cycles. A custom sequencing primer is required for Read 1 (16005986, Bio-Rad; included in the kit).