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08:48
Bio-energetics Investigation of Candida albicans Using Real-time Extracellular Flux Analysis
Published on: March 19, 2019
Mitochondrial two-component signaling systems in Candida albicans.
John Mavrianos1, Elizabeth L Berkow, Chirayu Desai
1Public Health Research Institute, University of Medicine and Dentistry of New Jersey, Newark, New Jersey, USA.
Eukaryotic Cell
|April 16, 2013
Summary
The pathogenic fungus Candida albicans has a two-component signaling protein, Srr1, localized to mitochondria. This protein regulates mitochondrial genes and programmed cell death (apoptosis), highlighting conserved signaling pathways.
Area of Science:
- Microbiology
- Cell Biology
- Evolutionary Biology
Background:
- Two-component signal transduction pathways are crucial for microbial environmental responses, originating in prokaryotes and transferred to eukaryotes.
- These pathways were inherited by eukaryotes from ancestral cyanobacteria via endosymbiotic lateral gene transfer.
Purpose of the Study:
- To investigate the presence and function of two-component signaling pathway elements in the mitochondria of Candida albicans.
- To determine the evolutionary origins and functional role of the Srr1 protein in C. albicans.
Main Methods:
- Utilized fluorescence microscopy to confirm mitochondrial localization of green fluorescent protein-tagged Srr1.
- Performed phylogenetic analysis to ascertain the evolutionary relationship of C. albicans Srr1 to bacterial homologs.
- Employed microarray analysis to assess gene expression changes in a srr1Δ/Δ null mutant.
Main Results:
- Identified a two-component response regulator, Srr1, with a mitochondrial targeting sequence in C. albicans, confirmed by microscopy.
- Phylogenetic analysis revealed C. albicans Srr1 is more closely related to marine bacterial two-component proteins than other fungal homologs.
- Microarray data showed altered expression of mitochondrial genes and significantly increased apoptosis in the srr1Δ/Δ mutant.
Conclusions:
- Candida albicans possesses a two-component response regulator protein, Srr1, localized to mitochondria, suggesting evolutionary conservation.
- Srr1 regulates a subset of genes involved in oxidative stress response and programmed cell death (apoptosis) in C. albicans mitochondria.
- This study provides the first evidence of a functional two-component signaling protein surviving within mitochondria in a lower eukaryote, impacting apoptosis pathways.
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