title: Hi-C reads for Phoronis australis
design: High-molecular-weight DNA was extracted from the ampulla of a single adult P. australis individual using chaotropic lysis buffer (CHAOS buffer: 4 M guanidine thiocyanate, 0.5% N-lauroyl sarcosine sodium, 25 mM Tris-HCl pH 8.0, and 0.1 M 2-mercaptoethanol), followed by phenol/chloroform/isoamyl alcohol (PCI; 25:24:1) extraction. In brief, the tissue was homogenized in 250 L of CHAOS buffer and incubated overnight at 55C. The lysate was mixed with 250 L of DNA extraction buffer (100 mM Tris-Cl pH 8.0, 10 mM EDTA, 0.1% SDS), vortexed with 250 L of PCI solution, and transferred to a pre-spun Phasemaker Tube. The mixture was centrifuged at 15,000  g for 5 min at 4C, and the aqueous phase was transferred to a new tube. DNA was precipitated by adding 600 L of isopropanol, followed by gentle mixing and centrifugation at 15,000  g for 20 min at 4C. The pellet was washed twice with 1 mL of 70% ethanol, each wash followed by centrifugation at 15,000  g for 10 min at 4C. After air-drying for 5 min, the DNA pellet was dissolved in UltraPure DNase/RNase-Free distilled water. For long-range information, dissected ampulla tissue was snap-frozen in liquid nitrogen, and a proximity ligation library was prepared using the Phase Genomics Proximo Hi-C Library Prep Kit with the restriction enzyme DpnII. This library was then sequenced on an Illumina NextSeq 2000 platform with 150 bp paired-end reads, generating 168 million read pairs.