skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Search for: All records

Creators/Authors contains: "Dolan, Elora G"

Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher. Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?

Some links on this page may take you to non-federal websites. Their policies may differ from this site.

  1. Goldman, Gustavo H (Ed.)
    ABSTRACT Infections caused by the emerging pathogenic yeastClavispora (Candida) lusitaniaecan be difficult to manage due to multi-drug resistance. Resistance to the frontline antifungal fluconazole (FLZ) inCandidaspp. is commonly acquired through gain-of-function (GOF) mutations in the gene encoding the transcription factor Mrr1. These activated Mrr1 variants enhance FLZ efflux via upregulation of the multi-drug transporter geneMDR1. Recently, it was reported that, unlike in the well-studiedCandida albicansspecies,C. lusitaniaeandCandida parapsilosiswith activated Mrr1 also have high expression ofCDR1, which encodes another multi-drug transporter with overlapping but distinct transported substrate profiles and Cdr1-dependent FLZ resistance. To better understand the mechanisms of Mrr1 regulation ofMDR1andCDR1, and other co-regulated genes, we performed Cleavage Under Targets and Release Using Nuclease (CUT&RUN) analysis of Mrr1 binding sites. Mrr1 bound the promoter regions ofMDR1andCDR1, as well asFLU1, which encodes another transporter capable of FLZ efflux. Mdr1 and Cdr1 independently contributed to the decreased susceptibility of theMRR1GOFstrains against diverse clinical azoles and other antifungals, including 5-flucytosine. A consensus motif, CGGAGWTAR, enriched in Mrr1-boundC. lusitaniaeDNA was also conserved upstream ofMDR1andCDR1across species, includingC. albicans. CUT&RUN and RNA-seq data were used to define the Mrr1 regulon, which includes genes involved in transport, stress response, and metabolism. Activated and inducible Mrr1 bound similar regions in the promoters of Mrr1 regulon genes. Our studies provide new evolutionary insights into the coordinated regulation of multi-drug transporters and potential mechanism(s) that aid secondary resistance acquisition in emergingCandida. IMPORTANCEUnderstanding antifungal resistance in emergingCandidapathogens is essential to managing treatment failures and guiding the development of new therapeutic strategies. Like otherCandidaspecies, the environmental opportunistic fungal pathogenClavispora(Candida)lusitaniaecan acquire resistance to the antifungal fluconazole by overexpression of the multi-drug efflux pump Mdr1 through gain-of-function (GOF) mutations in the gene encoding the transcription factor Mrr1. Here, we show thatC. lusitaniaeMrr1 also directly regulatesCDR1, another major multi-drug transporter gene, along withMDR1. In strains with activated Mrr1, upregulation ofMDR1andCDR1protects against diverse antifungals, potentially aiding the rise of other resistance mutations. Mrr1 also regulates several stress response and metabolism genes, thereby providing new perspectives into the physiology of drug-resistant strains. The identification of an Mrr1 binding motif that is conserved across strains and species will advance future efforts to understand multi-drug resistance acrossCandidaspecies. 
    more » « less
    Free, publicly-accessible full text available November 12, 2026