Related Experiment Video

Updated: May 3, 2026

Biolistic Transformation of a Fluorescent Tagged Gene into the Opportunistic Fungal Pathogen Cryptococcus neoformans
07:32

Biolistic Transformation of a Fluorescent Tagged Gene into the Opportunistic Fungal Pathogen Cryptococcus neoformans

Published on: March 19, 2015

9.6K

The link between morphotype transition and virulence in Cryptococcus neoformans

Linqi Wang1, Bing Zhai, Xiaorong Lin

  • 1Department of Biology, Texas A&M University, College Station, Texas, United States of America.

Plos Pathogens
|June 28, 2012
PubMed

Insights

The transcription factor Znf2 controls the switch between yeast and filamentous forms in the fungal pathogen Cryptococcus neoformans. High Znf2 levels promote filamentous growth but surprisingly reduce fungal virulence, impacting cell adhesion.

Area of Science:

  • Mycology
  • Pathogenesis
  • Molecular Biology

Background:

  • Cryptococcus neoformans is a significant human fungal pathogen.
  • Morphotype transition (yeast to filamentous form) is linked to virulence but the mechanism is unclear.
  • Pheromone signaling pathways govern mating-induced morphotype transition but have minimal direct role in virulence.

Purpose of the Study:

  • Investigate the molecular mechanisms linking morphotype transition and virulence in C. neoformans.
  • Determine the role of the transcription factor Znf2 in morphotype transition and pathogenicity.
  • Identify downstream factors of Znf2 involved in virulence.

Main Methods:

  • Genetic manipulation of Znf2 expression in C. neoformans.
  • In vitro and in vivo studies of fungal growth, morphology, and virulence in murine models.
  • Analysis of cell adhesion properties and downstream gene expression.

Main Results:

  • Filamentation occurs independently of pheromone signaling and mating, requiring the transcription factor Znf2.
  • High Znf2 expression induces filamentous growth under host-relevant conditions.
  • Overexpression of ZNF2 significantly reduces C. neoformans virulence in a murine cryptococcosis model.
  • Znf2 impacts cell adhesion, and its downstream factor Cfl1 regulates morphogenesis, adhesion, biofilm formation, and virulence.

Conclusions:

  • Znf2 is a key regulator bridging sex-independent morphotype transition and fungal pathogenicity.
  • Znf2-mediated changes in cell adhesion contribute to virulence.
  • Cfl1 is the first identified adhesin in Basidiomycota, highlighting the role of adhesion in pathogenesis.
  • Morphological plasticity and cell adhesion represent convergent evolutionary traits for pathogenesis in eukaryotic pathogens.

More Related Videos

Automated Measurement of Cryptococcal Species Polysaccharide Capsule and Cell Body08:08

Automated Measurement of Cryptococcal Species Polysaccharide Capsule and Cell Body

Published on: January 11, 2018

7.2K
Size Matters: Measurement of Capsule Diameter in Cryptococcus neoformans08:24

Size Matters: Measurement of Capsule Diameter in Cryptococcus neoformans

Published on: February 27, 2018

13.5K

Related Concept Videos

Cystic Fibrosis: Pathogenesis01:23

Cystic Fibrosis: Pathogenesis

Cystic fibrosis (CF), an autosomal recessive disorder, significantly affects the function of exocrine glands. This genetically inherited disease is characterized by the production of thick and sticky mucus, which can severely affect various organs and systems in the body.
CF is primarily caused by a genetic mutation in a chromosome 7 gene coding for the cystic fibrosis transmembrane conductance regulator (CFTR) protein. The most common gene mutation leading to CF is the ΔF508 mutation,...
1.1K
Transduction01:16

Transduction

Among the three main modes of HGT—transformation, conjugation, and transduction—transduction is unique in that it is mediated by bacteriophages, or bacterial viruses.Transduction occurs in two ways. Generalized transduction occurs during the lytic cycle of a bacteriophage infection. In this process, bacteriophages infect bacterial cells, replicate within them, and ultimately cause cell lysis, releasing newly assembled virions. Occasionally, random fragments of the bacterial genome...
3.0K
Fungal Phylum Microsporidia01:28

Fungal Phylum Microsporidia

Microsporidia are a group of obligate intracellular fungi that were initially classified as protists but were later reclassified based on phylogenetic, molecular, and structural evidence linking them to the Chytridiomycota. These unicellular, non-motile organisms are highly specialized parasites that infect a wide range of animal hosts, including humans. They have evolved extensive genomic and metabolic reductions, making them highly dependent on their hosts for survival.Morphology and Genomic...
782
Evolution of New Traits in Microbes01:24

Evolution of New Traits in Microbes

Microorganisms evolve rapidly due to their large population sizes and short generation times, often exhibiting measurable changes within days under laboratory conditions. Natural selection acts on standing genetic variation, enabling the retention and amplification of beneficial traits that confer fitness advantages in changing environments.Adaptive Pigment Regulation in RhodobacterIn Rhodobacter, a genus of purple non-sulfur bacteria, light-harvesting pigments such as bacteriochlorophyll and...
199
Colonisation of Pathogens01:25

Colonisation of Pathogens

Pathogen colonization of host tissues is a critical step in the development of infectious diseases. Various pathogenic microorganisms, including bacteria, fungi, viruses, and protozoa, have evolved complex strategies to attach to, invade, and persist within host environments. These mechanisms enable pathogens to establish infections, evade immune responses, and resist antimicrobial treatments.Attachment to Host CellsIn bacteria, colonization typically begins with adherence to host epithelial...
77
Regulation of Bacterial Virulence01:28

Regulation of Bacterial Virulence

Pathogenic bacteria employ a range of regulatory mechanisms to modulate the expression of virulence genes in response to environmental and host-derived signals. These mechanisms ensure that virulence factors are expressed only under favorable conditions, thereby optimizing infection and survival strategies.Mechanisms of Virulence RegulationKey regulatory strategies include:Two-Component Systems: These consist of a membrane-bound sensor kinase and a cytoplasmic response regulator. Environmental...
76