IL-4-induced phosphorylation of RNA polymerase II in vivo is inhibited by H7.

³²P-orthophosphate-labeled Ramos cells were left untreated or were pretreated with H7 (100 μmol/L) for 30 minutes and stimulated with IL-4 (100 ng/mL) for 15 minutes, as indicated. (A) Nuclear extracts (10 μg) were separated on 5% SDS-PAGE and transferred to PVDF membrane. Autoradiography of the membrane: hypophosphorylated (hypo-P) and hyperphosphorylated (hyper-P) forms of RNA polymerase II are indicated. (B) RNA polymerase II was immunoprecipitated from³²P-orthophosphate-labeled Ramos cells and separated on SDS-PAGE before autoradiography. (C) 50 μg nuclear lysates from unlabeled Ramos cells were electrophoresed on SDS-PAGE, transferred to PVDF membrane, and subjected to immunoblotting with anti-RNA polymerase II antiserum.