title: GSM9682568: GBe3s31_WSU_H3K4me1; Homo sapiens; OTHER
library_construction_protocol: Cells were harvested, washed in cold PBS, and resuspended in nuclear extraction buffer. Intact nuclei were incubated with primary antibodies targeting mSWI/SNF complex subunits (SMARCC1, SMARCB1, SMARCA4) or histone modifications (H3K4me1, H3K4me3, H3K27ac), or IgG isotype control, followed by secondary antibody and protein A/G-Tn5 (pAG-Tn5) transposase fusion incubation. DNA was simultaneously fragmented and tagged by MgCl₂-activated Tn5 transposition at 37°C. Released tagged fragments were purified for library preparation. CUT&Tag libraries were prepared in-house using the CUT&Tag protocol (Kaya-Okur et al., 2019). Libraries were sequenced by Novogene on an Illumina instrument.