Disruption of the sphingolipid Delta8-desaturase gene causes a delay in morphological changes in Candida albicans.
Ceramides and glycosylceramides, including desaturated long-chain bases, are present in most fungi as well as animals and plants. However, as the budding yeast Saccharomyces cerevisiae is not capable of desaturating long-chain bases, little is known about the physiological roles of these compounds in fungi. To investigate the necessity of desaturation of long-chain backbones in ceramides and glucosylceramides in fungal cells, we have identified and characterized a sphingolipid Delta8-desaturase (SLD) gene from the pathogenic yeast Candida albicans. Gene disruption of the C. albicans SLD homologue led to the accumulation of (E)-sphing-4-enine, a main substrate for the SLD enzyme. Introducing the Candida SLD gene homologue into these mutant cells resulted in the recovery of synthesis of (4E, 8E)-sphinga-4,8-dienine and this gene homologue was therefore identified as a Ca-SLD gene. Additionally, the sld disruptant of C. albicans had a decreased hyphal growth rate compared with the wild-type strain. These results suggest that Delta8-desaturation of long-chain bases in ceramides plays a role in the morphogenesis of C. albicans.
Oura
Takahiro
T
Department of Life Science, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259-B5 Nagatsuta, Midori-ku, Yokohama, Kanagawa 266-8501, Japan.
Kajiwara
Susumu
S
Department of Life Science, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259-B5 Nagatsuta, Midori-ku, Yokohama, Kanagawa 266-8501, Japan.
D000595:Amino Acid Sequence; D002176:Candida albicans / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development*; D003470:Culture Media; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017353:Gene Deletion; D015966:Gene Expression Regulation, Fungal; D025301:Hyphae / Q000254:growth & development; D008969:Molecular Sequence Data; D010088:Oxidoreductases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D010641:Phenotype; D017422:Sequence Analysis, DNA; D013107:Sphingolipids / Q000378:metabolism*
D003470:Culture Media; D005656:Fungal Proteins; D013107:Sphingolipids; D010088:Oxidoreductases; C115532:sphingolipid desaturase