A DNA-Binding Protein Is Required for Termination of Transcription by RNA Polymerase I in Xenopus laevis

Abstract

We describe a partially fractionated in vitro transcription system from Xenopus laevis for the assay of transcription termination by RNA polymerase I. Termination in vitro was found to require a specific terminator sequence in the DNA and a DNA-binding protein fraction that produces a footprint over the terminator sequence.