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The Aspergillus pH-responsive transcription factor PacC regulates virulence

Elaine Bignell1, Susana Negrete-Urtasun, Ana Maria Calcagno

  • 1Department of Infectious Diseases, Imperial College London, London W12 0NN, UK. e.bignell@imperial.ac.uk

Molecular Microbiology
|February 3, 2005
PubMed

Insights

The Aspergillus nidulans PacC protein is crucial for fungal virulence in pulmonary aspergillosis. Disrupting its pH response pathway significantly reduces the pathogen

Area of Science:

  • Medical Mycology
  • Molecular Pathogenesis
  • Host-Pathogen Interactions

Background:

  • Pathogen adaptation to host environments is essential for disease initiation.
  • Pulmonary aspergillosis is a serious opportunistic infection.
  • The role of pH regulation in fungal virulence is increasingly recognized.

Purpose of the Study:

  • To investigate the role of the Aspergillus nidulans PacC-mediated pH response in the pathogenesis of pulmonary aspergillosis.
  • To determine how PacC influences fungal adaptation and virulence within the host.

Main Methods:

  • Utilized mutational analysis in Aspergillus nidulans to study the PacC transcription factor.
  • Infected neutropenic mice models to assess fungal virulence.
  • Examined the impact of blocking pH signal transduction and PacC proteolytic processing.

Main Results:

  • Elimination or disruption of PacC function significantly attenuated virulence in a murine model of pulmonary aspergillosis.
  • Alkali-sensitive mutants exhibited limited fungal growth in vivo and reduced inflammatory cell infiltration.
  • Constitutive activation of PacC led to increased mortality and extensive fungal invasive growth.

Conclusions:

  • The Aspergillus nidulans PacC transcription factor plays a pivotal role in pulmonary pathogenesis.
  • PacC-mediated pH response is essential for fungal adaptation and virulence.
  • Targeting the PacC pathway could be a potential strategy for treating aspergillosis.

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