title: Illumina NovaSeq 6000 paired end sequencing
library_construction_protocol: Somatic nuclei were isolated from a caryonidal mass culture seven day post self-fertilization. ~10 μg of genomic DNA were purified from 500 ml mass culture in early stationary phase (5*10^5 Paramecium cells). The culture was cleaned up by filtration through 8 layers of gauze, cells concentrated on a Nitex filter (Nylon-Netzfilter, 10 μm pore size, 47 mm, Merck KGaA) and pelleted by centrifugation at 800 xRCF for 3 min. Collected cells were stored 1h in Volvic® water before cell lysis to reduce bacterial load. Cells were homogenized in 4 ml of lysis buffer (0.25 M sucrose; 10 mM MgCl2; 10 mM Tris pH 6.8; 0.2% NP40) (Arnaiz et al., 2012) by repeated crushing in a syringe barrel (20 ml, 60x25 hypodermic needle). Cell content was washed in 10ml of lysis buffer and macronuclei (MACs) isolated by centrifugation at 1000 xRCF for 15 min at 4°C. Isolated MACs were pre-lysed and gDNA extracted with the NucleoSpin® Tissue Kit following manufacturer's instructions for DNA isolation from cultured cells. Illumina libraries were prepared with the TruSeq DNA Nano kit.