title: GSM7504775: snRNASeq_BA01_and_BA08; Homo sapiens; RNA-Seq
library_construction_protocol: Adipose tissue biopsies were collected from subcutaneous abdominal adipose tissue.  Frozen adipose tissue (~100mg) was pulverized under liquid nitrogen and homogenized in 2mL of homogenization buffer (5mM MgCl2, 25mM Tris Buffer pH 8.0, 25mM KCL, 250mM sucrose, 1µm DDT, 1 x protease inhibitor, 0.2 U/µL SUPERase•In RNase Inhibitor (Thermofisher Scientific) in nuclease-free water) with a glasscol homogenizer. The homogenate was incubated for 30 minutes on ice with the addition of Triton-X100 (0.1% v/v) with regular vortexing. Samples were filtered through a 100µm and 40µm strainer (BD Falcon), centrifuged at 2,700g for 10 min at 4°C, resuspended in homogenization buffer and recentrifuged again at 2,700g for 10 min at 4°C. The pellet was then re-suspended in 1mL nuclei isolation medium (5mM MgCl2, 25mM Tris Buffer pH 8.0, 25mM KCL, 1 mM EDTA, 0.2 U/µL Ribolock RNAase inhibitor, 1% BSA in nuclease-free water) and centrifuged at 2,700g for 10 min at 4°C. Following re-suspension in 500µL nuclei isolation medium, sample was filtered 10 x with a 25g syringe prior to being counted. Single-nuclei suspension (40K/mL)  was distributed into eight wells of a 384-well source plate (Takara) and dispensed onto a ICELL8® 350v Chip (Takara) using an ICELL8 MultiSample NanoDispenser (MSND, Takara). Following dispense, the chip nanowells were imaged using the ICELL8 Imaging Station to identify nanowells containing a single nucleus. Only these nanowells were subjected for downstream dispenses. After imaging, the chip was subjected to freeze-thaw to lyse the cells/nuclei, followed by a 3 min incubation at 72oC to denature the RNA. Selected nuclei were subjected to first-strand cDNA synthesis initiated by oligo dT primer (SMART-Seq ICELL8 CDS), followed by template switching with template switching oligo (SMART-Seq ICELL8 oligonucleotide) for 2nd strand cDNA synthesis, prior to unbiased amplification of full-length cDNA. Synthesized full-length cDNA was tagmented by TDE1 (Illumina Tagment DNA enzyme) and amplified using forward (i5) and reverse (i7) indexing primers. Each single nucleus was indexed by a unique combination of 1 of 72 forward and 1 of 72 reverse indexing primers allowing for downstream identification. Collected cDNA was purified twice using a 1:1 proportion of AMPure XP beads (Beckman, A63880), further amplified according to manufacturer's instructions and purified again at a 1:1 proportion of AMPure XP beads. The resultant sequencing-ready cDNA library was assessed for concentration by fluorometer (Qubit) and quality by electrophoresis (Agilent Bioanalyzer high sensitivity DNA chips) respectively. Libraries were sequenced with Illumina HiSeq 4000.