title: A novel family of dehydrin-like proteins is involved in stress response in the human fungal pathogen Aspergillus fumigatus.
abstract: During a search for genes controlling conidial dormancy in Aspergillus fumigatus, two dehydrin-like genes, DprA and DprB, were identified. The deduced proteins had repeated stretches of 23 amino acids that contained a conserved dehydrin-like protein (DPR) motif. Disrupted DprAΔ mutants were hypersensitive to oxidative stress and to phagocytic killing, whereas DprBΔ mutants were impaired in osmotic and pH stress responses. However, no effect was observed on their pathogenicity in our experimental models of invasive aspergillosis. Molecular dissection of the signaling pathways acting upstream showed that expression of DprA was dependent on the stress-activated kinase SakA and the cyclic AMP-protein kinase A (cAMP-PKA) pathways, which activate the bZIP transcription factor AtfA, while expression of DprB was dependent on the SakA mitogen-activated protein kinase (MAPK) pathway, and the zinc finger transcription factor PacC. Fluorescent protein fusions showed that both proteins were associated with peroxisomes and the cytosol. Accordingly, DprA and DprB were important for peroxisome function. Our findings reveal a novel family of stress-protective proteins in A. fumigatus and, potentially, in filamentous ascomycetes.
authors.affiliation: Unité des Aspergillus, Institut Pasteur, 75015 Paris, France. jwong@pasteur.fr
authors.forename: Joanne
authors.initials: J
authors.lastname: Wong Sak Hoi
authors.forename: Claude
authors.initials: C
authors.lastname: Lamarre
authors.forename: Rémi
authors.initials: R
authors.lastname: Beau
authors.forename: Isabelle
authors.initials: I
authors.lastname: Meneau
authors.forename: Adokiye
authors.initials: A
authors.lastname: Berepiki
authors.forename: Annick
authors.initials: A
authors.lastname: Barre
authors.forename: Emilia
authors.initials: E
authors.lastname: Mellado
authors.forename: Nick D
authors.initials: ND
authors.lastname: Read
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Latgé
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001228:Aspergillosis; D001232:Aspergillus fumigatus / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology*; D002374:Catalase / Q000378:metabolism; D004229:Dithiothreitol / Q000494:pharmacology; D057075:Enzyme Assays; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D006801:Humans; D006863:Hydrogen-Ion Concentration; D020935:MAP Kinase Signaling System; D051379:Mice; D018832:Molecular Chaperones / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D009997:Osmotic Pressure; D010084:Oxidation-Reduction; D020675:Peroxisomes / Q000201:enzymology; D010641:Phenotype; D016415:Sequence Alignment; D017384:Sequence Deletion; D013172:Spores, Fungal / Q000235:genetics*; D013312:Stress, Physiological; D014158:Transcription, Genetic; D056811:Unfolded Protein Response / Q000187:drug effects
chemical_list: D005656:Fungal Proteins; D018832:Molecular Chaperones; D002374:Catalase; D004229:Dithiothreitol