a, Statistical outcome of FACS analysis of apoptosis of cells treated with siNC or siH2A.Z oligonucleotides. Annexin is used as a marker of apoptotic cells; DAPI is 4′,6-diamidino-2-phenylindole, a nuclear marker. b, Representative images of cells undergoing senescence (within boxed regions), shown by β-galactosidase staining. c, Cell-cycle analysis of siNC or siH2A.Z HeLa cells. Cells were pulse labelled with BrdU and stained with propidium iodide (PI), and then analysed by FACS. d, Western blots showing the H2A.Z level when cells are released from arrest at G2/M phase after treatment with IAA. AID, auxin-inducible degron. e, Volcano plot showing genome-wide expression dynamics after H2AFZ knockdown; n = 33,835. Genes with a log2(fold change) of 1 or more and P-values of less than 0.01 were selected as differentially expressed genes. f, Real-time PCR analysis of gene expression in siNC or siH2A.Z cells. The expression level was normalized to that of the glyceraldehyde-3-phosphate dehydrogenase gene (GAPDH). g, Left, diagram showing the LacO/LacI targeting system in A03_1 cells. An interaction between a LacI–Cherry-tagged histone and an enhanced green fluorescent protein (EGFP)-tagged ORC protein would result in an overlap of green fluorescence with red fluorescence. Right, there is no interaction in this experiment between ORC1 and H2A or H2A.Z. Scale bar, 5 μm. h, Western blot analysis of the enrichment of H4K20me2, H3K36me3 (negative control), SUV420H1, ORC1, ORC2 and MCM2 on H2A or H2A.Z nucleosomes from G1-phase-synchronized cells. Data in panel a are means; n = 2 biological replicates, with dot plots overlaid. Data in panels c, f are means ± s.e.m.; n = 3 biological replicates; two-tailed unpaired t-test. The β-galactosidase staining in panel b, the FACS results in c, the western blots in d, h, and the fluorescence image in g were independently repeated three times with similar results. H4 was used as a loading control and sample processing control in d and h. For gel source data, see Supplementary Fig. 1. For imaging source data, see Supplementary Fig. 2. For the FACS gating strategy, see Supplementary Fig. 3. Source data