Fig 1: FBXO42 mediates global chromatin remodeling in an RBPJ-dependent manner.(A) WT and FBXO42 KO cells were cotransfected with cSFB-RBPJ– and Myc-tagged constructs encoding epigenetically modified proteins. Then, cell lysates were incubated with S-protein beads and blotted with antibodies against FLAG- or MYC-epitope tags. (B) WT and FBXO42 KO cells were cotransfected with cSFB-RBPJ– and Myc-tagged constructs encoding SWI/SNF complex proteins. Then, the cells were harvested and analyzed as described in (A). (C) Heatmap showing the differential interaction between chromatin factors and RBPJ in WT and FBXO42 KO cells as identified by MS. (D) Enrichment analysis of the differentially interacting proteins of heterochromatin components is shown on the basis of GO annotation. (E) Immunofluorescence detection of HP1a foci in WT and FBXO42 KO cells. Scale bars, 10 µm. (F) HP1a foci number and percentage of HP1a foci area were calculated using ImageJ software. (G) WT and FBXO42 KO cells were digested with micrococcal nuclease (MNase) for 3 min, and chromatin relaxation was monitored by the release of nucleosomes. (H) Chromatin association of the SWI/SNF subunits SMARCA2, SMARCA4, and SMARCC2 in WT and FBXO42 KO cells was analyzed using Western blotting after chromatin isolation. ORC2 served as the loading control. (I) WT and FBXO42 KO cells were digested with deoxyribonuclease (DNase) for 3 min and followed with agarose gel electrophoresis analysis. (J) Chromatin from WT and FBXO42 KO cells was isolated, and DNase I was digested and used as substrate for accessibility assay. (K and L) The heatmap view for ATAC-seq signal intensity at TSSs in WT and FBXO42 KO JURKAT cells. (M) ATAC-seq peaks; H3K4m1, H3K4m3, and H3K27ac ChIP-seq peaks; and DNase-seq peaks downloaded from ENCODE database at MYC locus were analyzed. (A), (B), and (E) to (J), n = 3. Quantitative data are presented as means ± SEM. P values were calculated using two-tailed Student’s t tests. *P < 0.05 and **P < 0.01.