The Hsp90 of Candida albicans can confer Hsp90 functions in Saccharomyces cerevisiae: a potential model for the processes that generate immunogenic fragments of this molecular chaperone in C. albicans infections.
During infections with a number of important eukaryotic pathogens the Hsp90 molecular chaperone of the pathogen is recognized as an immunodominant antigen by the host immune system. Yeast molecular genetics should allow study of the extent of sequence variation within conserved immunodominant epitopes on pathogen Hsp90s that is compatible with essential Hsp90 functions, as well as the processes that generate antigenic subfragments of these Hsp90s. The Hsp90 of the fungal pathogen Candida albicans was shown in this study to provide both essential and nonessential (pheromone signalling and mammalian steroid receptor activation) Hsp90 functions in Saccharomyces cerevisiae cells. Much of the C. albicans Hsp90 expressed in respiratory S. cerevisiae cells was shown to undergo a partial degradation in vivo, a degradation that closely resembles that of the native Hsp82 (one isoform of the homologous Hsp90) in S. cerevisiae. Allowing for the differences in the length of the charged linker region between the N- and C-terminal domains of C. albicans Hsp90 and S. cerevisiae Hsp82, these two proteins expressed in S. cerevisiae appear to give the same major degradation products. These Hsp90 fragments are similar to the products of incomplete Hsp90 degradation found in C. albicans cultures.
Panaretou
Barry
B
Department of Biochemistry and Molecular Biology, University College London, London WC1E 6BT, UK1.
Sinclair
Kirsty
K
Department of Biochemistry and Molecular Biology, University College London, London WC1E 6BT, UK1.
Prodromou
Chrisostomos
C
Department of Biochemistry and Molecular Biology, University College London, London WC1E 6BT, UK1.
Johal
Jasvinder
J
Department of Biochemistry and Molecular Biology, University College London, London WC1E 6BT, UK1.
Pearl
Laurence
L
Department of Biochemistry and Molecular Biology, University College London, London WC1E 6BT, UK1.
Piper
Peter W
PW
Department of Biochemistry and Molecular Biology, University College London, London WC1E 6BT, UK1.
D000946:Antigens, Fungal / Q000276:immunology; D015153:Blotting, Western; D002176:Candida albicans / Q000235:genetics* / Q000378:metabolism; D002177:Candidiasis / Q000276:immunology / Q000378:metabolism; D018841:HSP90 Heat-Shock Proteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000378:metabolism; D018869:Heat-Shock Response; D010446:Peptide Fragments / Q000276:immunology; D010675:Pheromones / Q000378:metabolism; D011965:Receptors, Glucocorticoid / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D015398:Signal Transduction
D000946:Antigens, Fungal; C074510:HSP82 protein, S cerevisiae; D018841:HSP90 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D010446:Peptide Fragments; D010675:Pheromones; D011965:Receptors, Glucocorticoid; D029701:Saccharomyces cerevisiae Proteins