Immunological analysis of eukaryotic transcription factor S-II in a HeLa cell lysate

Previous experiments using antibody suggested that a stimulatory protein of RNA polymerase II termed S-II is an essential component of accurate transcription in a HeLa cell lysate (1). In this work a radioimmunoassay system for S-II was developed and it was demonstrated that S-II and RNA polymerase II in a HeLa cell lysate could be separated by sucrose density gradient centrifugation. This suggested that S-II and RNA polymerase II do not exist as a complex in the HeLa cell lysate. Probably, S-II is integrated into the initiation complex when appropriate template DNA and nucleoside triphosphates are added to the lysate.