Mutant alleles of the essential 14-3-3 gene in Candida albicans distinguish between growth and filamentation.
The opportunistic fungal pathogen Candida albicans has the ability to exploit diverse host environments and can either reside commensally or cause disease. In order to adapt to its new environment it must respond to new physical conditions, nutrient sources, and the host immune response. This requires the co-regulation of multiple signalling networks. The 14-3-3 family of proteins is highly conserved in all eukaryotic species. These proteins regulate signalling pathways involved in cell survival, the cell cycle, and differentiation, and effect their functions via interactions with phosphorylated serines/threonines. In C. albicans there is only one 14-3-3 protein, Bmh1p, and it is required for vegetative growth and optimal filamentation. In order to dissect separate functions of Bmh1p in C. albicans, site-directed nucleotide substitutions were made in the C. albicans BMH1 gene based on studies in other species. Putative temperature-sensitive, ligand-binding and dimerization mutants were constructed. In addition two mutant strains identified through random mutagenesis were analysed. All five mutant strains demonstrated varying defects in growth and filamentation. This paper begins to segregate functions of Bmh1p that are required for optimal growth and the different filamentation pathways. These mutant strains will allow the identification of 14-3-3 target interactions and correlate the individual functions of Bmh1p to cellular processes involved in pathogenesis.
Palmer
Glen E
GE
Georgetown University School of Medicine, Department of Microbiology and Immunology, 3900 Reservoir Road, Washington DC 20036, USA.|Louisiana State University School of Medicine, Department of Microbiology, Immunology, and Parasitology, Center of Excellence in Oral and Craniofacial Biology, 1100 Florida Ave, Box F8-130 New Orleans, LA 70119, USA.
Johnson
Kevin J
KJ
Louisiana State University School of Medicine, Department of Microbiology, Immunology, and Parasitology, Center of Excellence in Oral and Craniofacial Biology, 1100 Florida Ave, Box F8-130 New Orleans, LA 70119, USA.
Ghosh
Sumana
S
Louisiana State University School of Medicine, Department of Microbiology, Immunology, and Parasitology, Center of Excellence in Oral and Craniofacial Biology, 1100 Florida Ave, Box F8-130 New Orleans, LA 70119, USA.
Sturtevant
Joy
J
Georgetown University School of Medicine, Department of Microbiology and Immunology, 3900 Reservoir Road, Washington DC 20036, USA.|Louisiana State University School of Medicine, Department of Microbiology, Immunology, and Parasitology, Center of Excellence in Oral and Craniofacial Biology, 1100 Florida Ave, Box F8-130 New Orleans, LA 70119, USA.
D048948:14-3-3 Proteins; D000483:Alleles; D002176:Candida albicans / Q000235:genetics / Q000254:growth & development* / Q000502:physiology*; D003470:Culture Media; D020043:Genes, Essential; D009154:Mutation; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism; D013172:Spores, Fungal / Q000502:physiology; D013696:Temperature
D048948:14-3-3 Proteins; C075852:BMH1 protein, S cerevisiae; D003470:Culture Media; D029701:Saccharomyces cerevisiae Proteins