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Measurements of Physiological Stress Responses in C. Elegans
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Measurements of Physiological Stress Responses in C. Elegans

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The stress responsive and morphologically regulated hsp90 gene from Paracoccidioides brasiliensis is essential to

André M Nicola1, Rosângela V Andrade, Alessandra S Dantas

  • 1Department of Cell Biology, University of Brasília, Brazil. anicola@aecom.yu.edu

BMC Microbiology
|September 24, 2008
PubMed
Abstract

Insights

The Pbhsp90 gene is essential for the survival of Paracoccidioides brasiliensis, a fungus causing a prevalent Latin American mycosis. Inhibiting HSP90 with specific drugs proved lethal to yeast cells, highlighting its therapeutic potential.

Area of Science:

  • Mycology
  • Molecular Biology
  • Pathogenesis

Background:

  • Paracoccidioides brasiliensis causes the most common systemic mycosis in Latin America.
  • Heat shock response and dimorphism are crucial for P. brasiliensis pathogenesis.
  • HSP90 (Heat Shock Protein 90) is a molecular chaperone vital for fungal physiology and pathogenesis.

Purpose of the Study:

  • Investigate the Pbhsp90 gene, its expression, and role in P. brasiliensis cell viability.
  • Explore the potential of HSP90 as an antifungal therapeutic target.

Main Methods:

  • Sequencing of Pbhsp90 cDNA.
  • Analysis of Pbhsp90 gene copy number.
  • Quantitative analysis of Pbhsp90 gene expression under different conditions (yeast phase, dimorphic transition, oxidative stress).
  • Treatment of P. brasiliensis yeast cells with HSP90 inhibitors (geldanamycin, radicicol).

Main Results:

  • Pbhsp90 is a single-copy gene.
  • Pbhsp90 is preferentially expressed in the yeast phase and overexpressed during dimorphic transition and oxidative stress.
  • HSP90 inhibitors geldanamycin and radicicol inhibited P. brasiliensis yeast growth in a dose-dependent manner.

Conclusions:

  • The Pbhsp90 gene encodes a stress-responsive protein essential for P. brasiliensis cell viability.
  • HSP90 is a validated target for antifungal therapy against P. brasiliensis.

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