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Published on: July 19, 2021
Ultrastructural Features of Cryptococcus neoformans Histone Deacetylases Null Mutant Strains
Daniel Oliveira da Mata1, Lucas da Costa Campos2, Martha Viviana Roa-Cordero3,4
1Graduation Program in Animal Biology, University of Brasilia, Brasilia, Brazil.
Indian Journal of Microbiology
|August 8, 2026
Summary
Histone deacetylase (HDAC) genes are crucial for Cryptococcus neoformans morphogenesis and virulence. Deleting HDAC genes alters budding patterns, cell wall thickness, and mitochondrial integrity, impacting host-pathogen interactions.
Area of Science:
- Mycology
- Molecular Biology
- Epigenetics
Background:
- Cryptococcus neoformans is an opportunistic fungal pathogen.
- Epigenetic regulation, particularly histone deacetylases (HDACs), influences C. neoformans virulence.
- HDAC gene deletion mutants exhibit reduced virulence.
Purpose of the Study:
- To investigate the ultrastructural changes in C. neoformans HDA1 and HOS2 null mutants.
- To elucidate the role of HDACs in fungal morphogenesis and host-pathogen interactions.
Main Methods:
- Scanning Electron Microscopy (SEM) for surface morphology.
- Transmission Electron Microscopy (TEM) for ultrastructure.
- Analysis of H99, hda1∆, hos2∆, and hda1∆hos2∆ mutant strains.
Main Results:
- SEM showed unipolar budding in H99, hda1∆, and hos2∆ strains, but multipolar budding in the hda1∆hos2∆ double mutant.
- The hos2∆ strain displayed a defective capsule.
- TEM revealed altered cell wall thickness and mitochondrial swelling in mutant strains, with signs of degeneration in the double mutant.
Conclusions:
- HDACs play a critical role in C. neoformans morphogenesis.
- Morphological alterations in HDAC mutants impact fungal cell structure and potentially host cell interactions.
- Targeting HDACs could be a strategy to control C. neoformans infections.
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