Effect of ER stress inducers on the epigenomic programming of KSHV regulatory control regions.

(A) Schematic of KSHV lytic control region, latency control region and terminal repeats region (TR) with primer positions a-h used for ChIP assays. Red triangles represent CTCF binding sites. (B-E) BCBL1 cells treated for 3 hrs with DMSO or 75 ug/ml Puro were assayed by ChIP for IgG or (B) RAD21, (C) CTCF, (D) RNA Polymerase II phosphoS5 (RNAPII-S5) and (E) RNA Polymerase II phosphoS2 (RNAPII-S2). (F) BCBL1 cells were treated with puromycin for 6 hr, processed for IP with antibody to IgG, SMC1 or RAD21 and then assayed by Western blot with antibody to RAD21, SMC3 or SMC1. (G) BCBL1 cells were treated with puromycin for 3 and 6 hr, subcellular fractionation was performed, and cytoplasmic, nucleoplasmic and chromatin fractions were analyzed by Western blotting. GAPDH (a cytoplasmic protein), and chromatin bound histone H3 protein were used as controls for subcellular fractionation.