Deletion of GEL2 encoding for a beta(1-3)glucanosyltransferase affects morphogenesis and virulence in Aspergillus fumigatus.
The first fungal glycosylphosphatidylinositol anchored beta(1-3)glucanosyltranferase (Gel1p) has been described in Aspergillus fumigatus and its encoding gene GEL1 identified. Glycosylphosphatidylinositol-anchored glucanosyltransferases play an active role in the biosynthesis of the fungal cell wall. We characterize here GEL2, a homologue of GEL1. Both homologues share common characteristics: (i) GEL1 and GEL2 are constitutively expressed during over a range of growth conditions; (ii) Gel2p is also a putative GPI-anchored protein and shares the same beta(1-3)glucanosyltransferase activity as Gel1p and (iii) GEL2, like GEL1, is able to complement the Deltagas1 deletion in Saccharomyces cerevisiae confirming that Gelp and Gasp have the same enzymatic activity. However, disruption of GEL1 did not result in a phenotype whereas a Deltagel2 mutant and the double mutant Deltagel1Deltagel2 exhibit slower growth, abnormal conidiogenesis, and an altered cell wall composition. In addition, the Deltagel2 and the Deltagel1Deltagel2 mutant have reduced virulence in a murine model of invasive aspergillosis. These data suggest for the first time that beta(1-3)glucanosyltransferase activity is required for both morphogenesis and virulence in A. fumigatus.
Mouyna
Isabelle
I
Institut Pasteur, Unité des Aspergillus, 25 rue du Docteur Roux, 75724 Paris cedex 15, France. imouyna@pasteur.fr
Morelle
Willy
W
Vai
Marina
M
Monod
Michel
M
Léchenne
Barbara
B
Fontaine
Thierry
T
Beauvais
Anne
A
Sarfati
Jacqueline
J
Prévost
Marie-Christine
MC
Henry
Christine
C
Latgé
Jean-Paul
JP
D000818:Animals; D001228:Aspergillosis / Q000382:microbiology*; D001232:Aspergillus fumigatus / Q000201:enzymology / Q000235:genetics / Q000254:growth & development* / Q000472:pathogenicity*; D005260:Female; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D017353:Gene Deletion; D005816:Genetic Complementation Test; D004693:Glucan Endo-1,3-beta-D-Glucosidase / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D009024:Morphogenesis; D010641:Phenotype; D017422:Sequence Analysis, DNA; D014170:Transformation, Genetic; D014774:Virulence
D005656:Fungal Proteins; C117939:1,3-beta-glucanosyltransferase; D004693:Glucan Endo-1,3-beta-D-Glucosidase