These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Multiple cis-acting sequences mediate upregulation of the MDR1 efflux pump in a fluconazole-resistant clinical Candida albicans isolate. Author: Hiller D, Stahl S, Morschhäuser J. Journal: Antimicrob Agents Chemother; 2006 Jul; 50(7):2300-8. PubMed ID: 16801405. Abstract: Overexpression of the MDR1 gene, which encodes a multidrug efflux pump of the major facilitator superfamily, is a frequent cause of resistance to the antimycotic agent fluconazole and other metabolic inhibitors in clinical Candida albicans strains. Constitutive MDR1 overexpression in such strains is caused by mutations in as yet unknown trans-regulatory factors. In order to identify the cis-acting sequences in the MDR1 regulatory region that mediate constitutive MDR1 upregulation, we performed a promoter deletion analysis in the genetic background of an MDR1-overexpressing clinical C. albicans isolate. We found that several different regions in the MDR1 promoter can mediate MDR1 overexpression in this isolate. In contrast, deletion of one of these regions abolished benomyl-induced MDR1 expression in a C. albicans laboratory strain. These results suggest that multiple transcription factors control expression of the MDR1 efflux pump in C. albicans and that the mutation(s) that causes constitutive MDR1 overexpression and drug resistance in clinical C. albicans isolates affects the activities of several of these transcription factors.[Abstract] [Full Text] [Related] [New Search]