Candida albicans, a pathogenic yeast, is the cause of fungal infections in immune-compromised patient populations including AIDS patients. These infections are treated with antifungal drugs including the azole fluconazole. Extensive azole use has resulted in resistance which is a growing and significant problem. As molecular mechanisms of resistance are identified, it becomes important to understand the pathways which regulate these mechanisms in both susceptible and resistant strains. Currently, little is known about the transcriptional regulation of the ERG11 gene in C. albicans, the product of which is the target of the azole drugs and a biosynthetic step in the synthesis of ergosterol, the fungal equivalent of cholesterol. The Overall Goal of this research is to understand the interactions between azoles and C. albicans by studying the expression and regulation of genes associated with resistance. This proposal focuses on the transcriptional regulation of ERG11.
The Specific Aims are: 1) To characterize regions of the ERG11 promoter that are important for transcriptional regulation. 2) To identify and characterize the transcription factors that regulate the ERG11 promoter. 3) To characterize the newly described ECM22 transcription factor in C. albicans for its effect on ERG11 and azole susceptibility; disruption of gene results in azole hyper-susceptibility. 4) To characterize additional C. albicans genes, identified by genomic approaches, that regulate azole susceptibility. The interactions between azoles and fungal cells, and the resulting azole drug resistance, will continue to be a clinically significant issue for the foreseeable future. Understanding the transcriptional regulation of ERG11 and of ergosterol biosynthesis, and understanding how fungal cells respond to azole drugs may lead to improvements in diagnosis, treatment and prevention of fungal infections and of resistance. ? ? ?

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
Research Project (R01)
Project #
5R01DE011367-13
Application #
7062146
Study Section
Special Emphasis Panel (ZRG1-AARR-1 (04))
Program Officer
Lunsford, Dwayne
Project Start
1994-09-30
Project End
2008-04-30
Budget Start
2006-05-01
Budget End
2007-04-30
Support Year
13
Fiscal Year
2006
Total Cost
$361,832
Indirect Cost
Name
Seattle Biomedical Research Institute
Department
Type
DUNS #
070967955
City
Seattle
State
WA
Country
United States
Zip Code
98109
Bhattacharya, Somanon; Esquivel, Brooke D; White, Theodore C (2018) Overexpression or Deletion of Ergosterol Biosynthesis Genes Alters Doubling Time, Response to Stress Agents, and Drug Susceptibility in Saccharomyces cerevisiae. MBio 9:
Zavrel, Martin; White, Theodore C (2015) Medically important fungi respond to azole drugs: an update. Future Microbiol 10:1355-73
Esquivel, Brooke D; Smith, Adam R; Zavrel, Martin et al. (2015) Azole drug import into the pathogenic fungus Aspergillus fumigatus. Antimicrob Agents Chemother 59:3390-8
Zavrel, Martin; Hoot, Sam J; White, Theodore C (2013) Comparison of sterol import under aerobic and anaerobic conditions in three fungal species, Candida albicans, Candida glabrata, and Saccharomyces cerevisiae. Eukaryot Cell 12:725-38
Brown, Gordon D; Denning, David W; Gow, Neil A R et al. (2012) Hidden killers: human fungal infections. Sci Transl Med 4:165rv13
Hoot, Samantha J; Smith, Adam R; Brown, Ryan P et al. (2011) An A643V amino acid substitution in Upc2p contributes to azole resistance in well-characterized clinical isolates of Candida albicans. Antimicrob Agents Chemother 55:940-2
Hoot, Samantha J; Brown, Ryan P; Oliver, Brian G et al. (2010) The UPC2 promoter in Candida albicans contains two cis-acting elements that bind directly to Upc2p, resulting in transcriptional autoregulation. Eukaryot Cell 9:1354-62
Mansfield, Bryce E; Oltean, Hanna N; Oliver, Brian G et al. (2010) Azole drugs are imported by facilitated diffusion in Candida albicans and other pathogenic fungi. PLoS Pathog 6:e1001126
Marie, Chelsea; White, Theodore C (2009) Genetic Basis of Antifungal Drug Resistance. Curr Fungal Infect Rep 3:163-169
Richards, Theresa S; Oliver, Brian G; White, Theodore C (2008) Micafungin activity against Candida albicans with diverse azole resistance phenotypes. J Antimicrob Chemother 62:349-55

Showing the most recent 10 out of 38 publications