Research

Epigenetic inheritance of an inducibly nucleosome-depleted promoter and its associated transcriptional state in the apparent absence of transcriptional activators

Ryosuke Ohsawa , Melissa Adkins and Jessica K Tyler

Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, USA

author email corresponding author email

Epigenetics & Chromatin 2009, 2:11doi:10.1186/1756-8935-2-11

Published:	11 September 2009

Abstract

Background

Dynamic changes to the chromatin structure play a critical role in transcriptional regulation. This is exemplified by the Spt6-mediated histone deposition on to histone-depleted promoters that results in displacement of the general transcriptional machinery during transcriptional repression.

Results

Using the yeast PHO5 promoter as a model, we have previously shown that blocking Spt6-mediated histone deposition on to the promoter leads to persistent transcription in the apparent absence of transcriptional activators in vivo. We now show that the nucleosome-depleted PHO5 promoter and its associated transcriptionally active state can be inherited through DNA replication even in the absence of transcriptional activators. Transcriptional reinitiation from the nucleosome-depleted PHO5 promoter in the apparent absence of activators in vivo does not require Mediator. Notably, the epigenetic inheritance of the nucleosome-depleted PHO5 promoter through DNA replication does not require ongoing transcription.

Conclusion

Our results suggest that there may be a memory or an epigenetic mark on the nucleosome-depleted PHO5 promoter that is independent of the transcription apparatus and maintains the promoter in a nucleosome-depleted state through DNA replication.