title: GSM9202855: NKO-NPM1 WT_NPM1; Homo sapiens; ChIP-Seq
library_construction_protocol: NKO-NPM1 WT and NKO-NPM1 K257R HK-2 cells were cross-linked with 1% formaldehyde for 10 min at room temperature to stabilize DNA-protein complexes. The reaction was quenched with 0.125 M glycine for 5 min. Cells were then lysed in ice-cold lysis buffer (10 mM HEPES pH 7.5, 0.1 mM EDTA, 0.5% NP-40) supplemented with protease inhibitor cocktail. Nuclei were pelleted by centrifugation at 2,000 × g for 10 min at 4°C, and chromatin was fragmented to an average size of 100–500 bp using sonication.Fragmented chromatin was immunoprecipitated overnight at 4°C with anti-NPM1 antibody or rabbit IgG, followed by incubation with protein G-agarose beads. After washing, bound complexes were eluted and reverse-crosslinked. DNA from both input and IP samples was purified by phenol-chloroform extraction. Sequencing libraries were constructed using the VAHTS Universal DNA Library Prep Kit for Illumina V3 (Vazyme, China) and subjected to sequencing on an Illumina Novaseq™ X Plus platform.