Exonic H2Bub1 levels are splicing independent. (A) HeLa cells were transfected with siRNA oligonucleotides (SMARTpool) directed against PTBP1 and PTBP2 (siPTPB) or against lacZ (siLacZ) as a control and 72 h later were analyzed by qRT-PCR with primers corresponding to the indicated exons. All values were normalized to GAPDH in the same sample and represent averages from duplicate qPCR reactions. Error bars, SD. Similar results were obtained in three independent experiments. (B) Cells were treated as in panel A and subjected to ChIP analysis with antibodies specific for H2B and H2Bub1. Immunoprecipitated DNA was quantified by qPCR with primers specific for the indicated regions. Bars indicate H2Bub1 ChIP readings normalized to H2B and represent averages from four experiments. H2Bub1/H2B ratios in siPTBP samples were normalized to siLacZ samples, which were defined as 1.0.
