Logo image
Cross-talk between Transcriptional Regulators of Multidrug Resistance in Saccharomyces cerevisiae
Journal article   Open access   Peer reviewed

Cross-talk between Transcriptional Regulators of Multidrug Resistance in Saccharomyces cerevisiae

Xiaoting Zhang, Zhifeng Cui, Tokichi Miyakawa and W. Scott Moye-Rowley
The Journal of biological chemistry, Vol.276(12), pp.8812-8819
03/23/2001
DOI: 10.1074/jbc.M010686200
PMID: 11134057
url
https://doi.org/10.1074/jbc.M010686200View
Published (Version of record) Open Access

Abstract

Multiple or pleiotropic drug resistance often arises in the yeast Saccharomyces cerevisiae due to genetic alterations of the functional state of the Cys6-Zn(II)2 transcription factors Pdr1p and Pdr3p. Single amino acid substitutions give rise to hyperactive forms of these regulatory proteins, which in turn cause overproduction of downstream target genes that directly mediate multidrug resistance. Previous work has identified a novel Cys6-Zn(II)2 transcription factor designated Yrr1p as mutant forms of this protein confer high level resistance to the cell cycle inhibitor reveromycin A and DNA damaging agent 4-nitroquinoline-N-oxide. In the present study, we demonstrate that Yrr1p also mediates oligomycin resistance through activation of the ATP-binding cassette transporter-encoding geneYOR1. Additionally, insertion of triplicated copies of the hemagglutinin epitope in the C-terminal region of Yrr1p causes the protein to behave as a hyperactive regulator of transcription. We have found that YRR1 expression is both controlled in a Pdr1p/Pdr3p-dependent manner and autoregulated. Chromatin immunoprecipitation experiments also show that Yrr1p associates with target promoters in vivo. Together these data argue that the signal generated by activation of Pdr1p and/or Pdr3p can be amplified through the action of these transcriptional regulatory proteins on downstream target genes, like YRR1, that also encode transcription factors.

Details

Metrics

Logo image