Dual detection of fungal infections in Drosophila via recognition of glucans and sensing of virulence factors

Cell. 2006 Dec 29;127(7):1425-37. doi: 10.1016/j.cell.2006.10.046.


The Drosophila immune system discriminates between various types of infections and activates appropriate signal transduction pathways to combat the invading microorganisms. The Toll pathway is required for the host response against fungal and most Gram-positive bacterial infections. The sensing of Gram-positive bacteria is mediated by the pattern recognition receptors PGRP-SA and GNBP1 that cooperate to detect the presence of infections in the host. Here, we report that GNBP3 is a pattern recognition receptor that is required for the detection of fungal cell wall components. Strikingly, we find that there is a second, parallel pathway acting jointly with GNBP3. The Drosophila Persephone protease activates the Toll pathway when proteolytically matured by the secreted fungal virulence factor PR1. Thus, the detection of fungal infections in Drosophila relies both on the recognition of invariant microbial patterns and on monitoring the effects of virulence factors on the host.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibody Formation
  • Beauveria / immunology
  • Beauveria / pathogenicity
  • Candida albicans / immunology
  • Candida albicans / pathogenicity
  • Carrier Proteins / genetics
  • Carrier Proteins / immunology*
  • Carrier Proteins / metabolism*
  • Drosophila / immunology
  • Drosophila / microbiology*
  • Drosophila Proteins / genetics
  • Drosophila Proteins / immunology
  • Drosophila Proteins / metabolism*
  • Glucans / immunology*
  • Immunity, Cellular
  • Intracellular Signaling Peptides and Proteins
  • Metarhizium / immunology
  • Metarhizium / pathogenicity
  • Models, Immunological
  • Polysaccharides / chemistry
  • Serine Endopeptidases / metabolism
  • Signal Transduction
  • Virulence Factors / immunology*


  • Carrier Proteins
  • Drosophila Proteins
  • GNBP3 protein, Drosophila
  • Glucans
  • Intracellular Signaling Peptides and Proteins
  • Polysaccharides
  • Virulence Factors
  • Serine Endopeptidases
  • psh protein, Drosophila