title: HiC read
design: Hi-C libraries were prepared using a DpnI-based protocol (Lieberman-Aiden et al., 2009). Young cladode tissues were crosslinked with 1% formaldehyde, quenched with 0.125 M glycine, washed, flash-frozen and lysed. Nuclei were digested overnight at 37 C with DpnI, heat-inactivated, and 5 overhangs were filled in with biotinylated nucleotides. Proximity ligation was then performed under dilute conditions to favor intramolecular events. After reversing crosslinks and removing RNA, DNA was purified; biotinylated junctions were captured on streptavidin beads, fragmented (~300500 bp), adapter-ligated, PCR-enriched, quantified by qPCR, validated by gel or Bioanalyzer, and sequenced on an Illumina NovaSeq 6000.