EngineeredControl of Cell Morphology In Vivo Reveals Distinct Roles for Yeast andFilamentous Forms of Candida albicans duringInfection
Open accessAbstract
It is widely assumed that the ability of Candida albicans to switch between different morphologies is required for pathogenesis. However, most virulence studies have used mutants that are permanently locked into either the yeast or filamentous forms which are avirulent but unsuitable for discerning the role of morphogenetic conversions at the various stages of the infectious process. We have constructed a strain in which this developmental transition can be externally modulated both in vitro and in vivo. This was achieved by placing one copy of the NRG1 gene (a negative regulator of filamentation) under the control of a tetracycline-regulatable promoter. This modified strain was then tested in an animal model of hematogenously disseminated candidiasis. Mice injected with this strain under conditions permitting hyphal development succumbed to the infection, whereas all of the animals injected under conditions that inhibited this transition survived. Importantly, fungal burdens were almost identical in both sets of animals, indicating that, whereas filament formation appears to be required for the mortality resulting from a deep-seated infection, yeast cells play an important role early in the infectious process by extravasating and disseminating to the target organs. Moreover, these infecting Candida yeast cells still retained their pathogenic potential, as demonstrated by allowing this developmental transition to occur at various time points postinfection. We demonstrate here the importance of morphogenetic conversions in C. albicans pathogenesis. This engineered strain should provide a useful tool in unraveling the individual contributions of the yeast and filamentous forms at various stages of the infectious process.
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The ability of C. albicans to reversibly change between blastospores and hyphae is a key virulence factor, and mutants that are unable to form hyphae have greatly attenuated virulence.
“The ability to reversibly change between blastospores and hyphae is a key virulence factor for this fungus, and mutants that are unable to form hyphae have greatly attenuated virulence [12,13].”
From Als3 Is a Candida albicans Invasin That Binds to Cadherins and Induces Endocytosis by Host Cells (2007) · cites this paper as [13]
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- Authors
- Saville, S. P., Lazzell, A. L., Monteagudo, C., & Lopez-Ribot, J. L.
- Affiliations
- The University of Texas at San Antonio Health Science Center (US)
- Universitat de València (ES)
- Corresponding author
- Saville, Stephen P.
- Venue
- Eukaryotic Cell
- Publisher
- American Society for Microbiology
- Published
- 2003-10
- Volume
- 2
- Issue
- 5
- Pages
- 1053-1060
- ISSN
- 1535-9778 (ISSN-L)
- 1535-9786
- PMC
- PMC219382
- OpenAlex
- W2133183053
- Cited by
- 655
- References
- 4
- Citations by year
- 2026: 12 · 2025: 19 · 2024: 20 · 2023: 21 · 2022: 23 · 2021: 32 · 2020: 40 · 2019: 31 · 2018: 31 · 2017: 36 · 2016: 27 · 2015: 33 · 2014: 53 · 2013: 40 · 2012: 30
- FWCI
- 10.36
- Type
- journal article
- Language
- en
- Open access
- diamond
- doi.org
- Locations
- Eukaryotic Cell (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- Burroughs Wellcome Fund
- U.S. Public Health Service (R03 A105447)
- Topics
- Health Sciences › Medicine › Infectious Diseases › Antifungal resistance and susceptibility
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Fungal and yeast genetics research
- Health Sciences › Medicine › Epidemiology › Fungal Infections and Studies
- Keywords
- Candida albicans, yeast-to-hypha transition, morphogenesis, neuregulin-1, fungal virulence, hyphal development, yeast cells, animal models of infection
- MeSH terms
- Animals, Brain, Candida albicans, Candidiasis, Cell Division, Doxycycline, Female, Genetic Engineering, Kidney, Mice, Inbred BALB C, Promoter Regions, Genetic, Repressor Proteins, Spleen, Yeasts, Gene Expression Regulation, Fungal, Survival Rate, Hyphae, Mice
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