Two subunits of wheat germ, calf thymus and human placenta DNA-dependent RNA polymerases II bind to DNA

Abstract

The subunits of RNA polymerase II enzymes were analyzed for their ability to bind to double stranded DNA. Partially purified RNA polymerases II from wheat germ and calf thymus were subjected to electrophoresis,in denaturing conditions, transferred to nitrocellulose filters and probed with radioactively labeled double stranded calf thymus DNA. Wheat germ polymerase subunits of 215 and 140 kilodaltons and calf thymus polymerase subunits of 185 and 140 kilodaltons bound 切 the DNA probes. Human placental RNA polymerase II was analysed by DNA crosslinking methods and was shown to contain two subunits of 240 and 195 kilodaltons that interact with the DNA probes. These results indicate that eukaryotic RNA polymerase enzymes may interact with DNA in a more complex fashion than prokaryotic enzymes, where only one subunit binds to DNA.