Fig. 6

pS187-H1.4 levels are independent of RNAP II progression. a HeLa cells were treated with DMSO (solvent control), 50 μM α-amanitin, 500 nM actinomycin D or 200 nM triptolide for 1 h. The abundance and phosphorylation of RNA polymerase II, H1.2, H1.4 and H1.5 were analyzed by immunoblotting whole-cell lysates with the indicated antisera. The numbers below each panel indicate densitometry for the treated samples relative to the DMSO control sample. b The levels of pS187-H1.4 at the promoters and gene bodies of housekeeping genes in HeLa cells treated with DMSO (solvent control), 50 μM α-amanitin, 500 nM actinomycin D or 200 nM triptolide for 1 h were assessed by ChIP-qPCR. Negative control ChIP assays employed non-immune rabbit immunoglobulin (rIg) in place of primary antisera. The data are expressed as percent relative to input DNA (mean ± s.e.m., *p < 0.05; **p < 0.01; ***p < 0.001)