RNA polymerase III promoter elements enhance transcription of RNA polymerase II genes

Abstract
Using transient expression assays in cultured human cells we have observed that RNA Polymerase III promoter sequences exert a positive cis-acting enhancer effect on RNA Polymerase II transcription. A DNA segment containing a copy of the Alu repeated element enhances transcription of the liver specific Haptoglobin related (Hpr) promoter in Hepatoma cell lines but not in HeLa cells. A tRNAPro gene acts as enhancer of the SV4O promoter both in Hepatoma and in HeLa cell lines. Transcription from the SV4O promoter is also enhanced by DNA segments containing only the box A or the box B of the tRNAPro promoter.