Publisher Summary This chapter focuses on three classes of nuclear DNA-dependent RNA
polymerases that have been identified in eukaryotic cells. Synthesis of mature RNA
molecules requires additional enzymes and factors other than those needed to bring about
accurate transcriptional initiation. For analysis by hybridization and SI nuclease digestion, it
is important first to remove the template DNA. Titrations both of DNA and of extract yield
nonlinear responses. At a constant extract concentration, measuring runoff transcription as a …