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Small-Scale Plasma Membrane Preparation for the Analysis of Candida albicans Cdr1-mGFPHis
Published on: June 13, 2021
Arv1 lipid transporter function is conserved between pathogenic and nonpathogenic fungi
Christina Gallo-Ebert1, Paula C McCourt, Melissa Donigan
1Venenum Biodesign, Genesis Biotechnology Group, Hamilton, NJ 08691, United States.
Fungal Genetics and Biology : FG & B
|December 7, 2011
Summary
The lipid transporter Arv1 is crucial for fungal cell survival against antifungal drugs by regulating gene expression and drug efflux. Its function is conserved in pathogenic fungi, and its absence reduces virulence.
Area of Science:
- Biochemistry
- Molecular Biology
- Mycology
Background:
- The lipid transporter Arv1 plays a role in sterol trafficking and biosynthesis in Saccharomyces cerevisiae.
- Arv1 homology domain (AHD) is conserved in pathogenic fungi like Candida albicans and Candida glabrata.
- Understanding Arv1's function is critical for developing new antifungal strategies.
Purpose of the Study:
- To investigate the role of Arv1 in antifungal drug susceptibility in Saccharomyces cerevisiae.
- To determine if the conserved AHD in pathogenic fungi is functionally equivalent to ScArv1.
- To explore the mechanism by which Arv1 influences antifungal resistance and virulence.
Main Methods:
- Gene deletion and ectopic expression in Saccharomyces cerevisiae.
- Phenotypic analysis of drug susceptibility and gene expression.
- Sterol trafficking assays.
- Virulence studies in a mouse model.
Main Results:
- Saccharomyces cerevisiae cells lacking Arv1 (Scarv1) exhibit high susceptibility to antifungal drugs.
- Scarv1 cells show defects in ERG gene expression, pleiotropic drug response, and efflux pump expression.
- Expression of Candida albicans or Candida glabrata Arv1 complements Scarv1 phenotypes, indicating conserved function.
- Arv1 is essential for sterol trafficking and its absence in Candida albicans renders the fungus avirulent in a mouse model.
Conclusions:
- The lipid transporter Arv1 is essential for antifungal drug tolerance in fungi.
- Conserved Arv1 function across different fungal species highlights its potential as a drug target.
- Arv1's role in sterol trafficking and gene regulation is critical for cell survival under antifungal stress.
- Arv1 deficiency significantly impacts fungal virulence, suggesting a link between drug resistance and pathogenicity.
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