A NOVEL MEDIATOR BETWEEN ACTIVATOR PROTEINS AND THE RNA POLYMERASE-II TRANSCRIPTION APPARATUS

One gene activator protein may interfere with the effects of another in eukaryotic cells. We report here that a hybrid yeast-herpes gene activator protein inhibits transcriptional activation by a thymidine-rich DNA element in yeast. This example of activator interference can be faithfully reproduced in vitro. Interference is reversed by a partially purified yeast component, but not by RNA polymerase II or various polymerase II transcription factors. We conclude that the partially purified yeast component is a novel factor, and we suggest this factor mediates the transcriptional activation process. © 1990.