Related Experiment Video
Updated: Jun 17, 2025
07:42
An Ex vivo Assay to Study Candida albicans Hyphal Morphogenesis in the Gastrointestinal Tract
Published on: July 1, 2020
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The ER-Resident Ras Inhibitor 1 (Eri1) of Candida albicans Inhibits Hyphal Morphogenesis via the Ras-Independent
Subhash Chandra Sethi1, Monika Bharati1, Yatin Kumar1
1School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
ACS Infectious Diseases
|August 9, 2024
Summary
In Candida albicans, Eri1
Area of Science:
- Mycology
- Molecular Biology
- Biochemistry
Background:
- Ras signaling and glycosylphosphatidylinositol (GPI) biosynthesis are mutually inhibitory in S. cerevisiae.
- In contrast, these pathways are mutually activated in C. albicans, controlling virulence.
- The role of Eri1, a GPI-GnT subunit, in C. albicans was previously unknown.
Purpose of the Study:
- To investigate the cellular and virulence role of CaEri1 in Candida albicans.
- To elucidate the interaction of CaEri1 with Ras signaling and GPI biosynthesis pathways.
Main Methods:
- Genetic manipulation of CaEri1 expression.
- Analysis of GPI biosynthesis, cell wall integrity, and hyphal morphogenesis.
- Biochemical assays including pull-down and Förster resonance energy transfer (FRET).
- Virulence studies in Galleria mellonella.
Main Results:
- CaEri1 is nonessential for C. albicans viability but its depletion impairs GPI biosynthesis and causes cell wall defects.
- Severe depletion of CaEri1 leads to hyperfilamentation, suggesting activation of Ras-dependent and independent pathways.
- CaEri1 interacts with CaRas1 indirectly via CaGpi2 and is downstream of other GPI-GnT subunits in inhibiting Ras-independent filamentation.
- CaERI1 exhibits unique intersubunit transcriptional cross-talk within the GPI-GnT.
- A heterozygous CaERI1 strain shows attenuated virulence and enhanced clearance in G. mellonella.
Conclusions:
- CaEri1 plays a crucial role in regulating GPI biosynthesis, cell wall integrity, and hyphal morphogenesis in C. albicans.
- CaEri1's interaction network differs from S. cerevisiae, highlighting pathway divergence.
- CaEri1 is a potential virulence factor and a target for antifungal strategies.
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