Two-component signal transduction in human fungal pathogens.
Signal transduction pathways provide mechanisms for adaptation to stress conditions. One of the most studied of these pathways is the HOG1 MAP kinase pathway that in Saccharomyces cerevisiae is used to adapt cells to osmostress. The HOG1 MAPK has also been studied in Candida albicans, and more recently observations on the Hog1p functions have been described in two other human pathogens, Aspergillus fumigatus and Cryptococcus neoformans. The important, but not surprising, concept is that this pathway is used for different yet similar functions in each of these fungi, given their need to adapt to different environmental signals. Current studies of C. albicans focus upon the identification of two-component signal proteins that, in both C. albicans and S. cerevisiae, regulate the HOG1 MAPK. In C. albicans, these proteins regulate cell wall biosynthesis (and, therefore, adherence to host cells), osmotic and oxidant adaptation, white-opaque switching, morphogenesis, and virulence of the organism.
Department of Microbiology & Immunology, Georgetown University Medical Center, Washington DC 20057, USA.
Michael
M
Kruppa
Richard
R
Calderone
D000222:Adaptation, Physiological; D000818:Animals; D005656:Fungal Proteins / Q000378:metabolism*; D006801:Humans; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D003904:Mitosporic Fungi / Q000378:metabolism / Q000472:pathogenicity / Q000502:physiology*; D009181:Mycoses / Q000382:microbiology; D015398:Signal Transduction; D014774:Virulence
C093538:ALS1 protein, Candida albicans; D005656:Fungal Proteins; D020928:Mitogen-Activated Protein Kinases; D020929:Mitogen-Activated Protein Kinase Kinases