title: GSM1182880: dRF24: 3h.LNA-C1 rep Xist CHART; Mus musculus; OTHER
library_construction_protocol: Nuclei, purified from cells crosslinked in 1% formaldehyde for 10 min, were further crosslinked with 3% formaldehyde for 30 min at room temperature.  Sheared chromatin, with a median size around 3kb, was incubated overnight with a mixture of biotinylated capture oligonucleotides that were complementary to Xist RNA.  The hybridized material was captured by streptavidin beads, and washed extensively before RNaseH elution. Enriched DNA was purified after formaldehyde crosslink reversal and subjected to library construction. Genome DNA of inputs and Xist CHART enriched DNA samples were fragmented by sonication, and the sequencing libraries was constructed by first repairing DNA-ends, A-tailing, ligating to universal adapters, and amplifying for 12 cycles with indexed primer.