High impact information on AUR1

• Yeast sphingolipids have particularly long acyl chains, and Aur1p, the inositol phosphorylceramide synthase that initiates yeast sphingolipid synthesis, was found to be located in the Golgi apparatus by both immunofluorescence and membrane fractionation, with its active site apparently in the Golgi lumen [1].
• Aureobasidin A, an inhibitor of the IPC synthase Aur1p completely blocks IPC biosynthesis at 0.5 micrograms/ml but does not block remodeling of glycosylphosphatidylinositol anchors even at concentrations up to 10 micrograms/ml [2].
• Sphingolipid synthesis as a target for antifungal drugs. Complementation of the inositol phosphorylceramide synthase defect in a mutant strain of Saccharomyces cerevisiae by the AUR1 gene [3].
• Subsequent sporulation and dissection of the aur1/aur1 delta diploid resulted in tetrads demonstrating 2:2 segregation of viable and nonviable spores, indicating that deletion of aur1 is lethal [4].
• From a genomic library of one such AUR1 mutant, the AUR1R (for aureobasidin resistant) mutant gene was isolated as a gene that confers resistance to AbA on wild-type cells [5].

Biological context of AUR1

• The IPC1 gene from Saccharomyces cerevisiae, which encodes inositolphosphorylceramide (IPC) synthase, was first identified as a novel and essential gene encoding resistance to the natural product antifungal aureobasidin A (AUR1) [6].
• We propose that the plotoplast fusion using dominant selective geneticin- and aureobasidin A-resistance markers and reporter genes is useful for the selection of hybrids from wine yeasts, which are homothallic and have low sporulation ability [7].
• Deletion of aur1 was accomplished in a diploid S. cerevisiae strain [4].
• To obtain a strain suitable for commercial use, an delta-integrative cassette devoid of bacterial DNA sequences was constructed that contains the AMY gene and aureobasidin A resistance gene (AUR1-C) as the selection marker [8].

Anatomical context of AUR1

• Thirdly, in the cells with a disrupted aur1 locus, pleiotropic morphological changes including disappearance of microtubules, degradation of tubulin and abnormal deposition of chitin were observed [5].

Associations of AUR1 with chemical compounds

• The AUR1 gene of Saccharomyces cerevisiae, mutations in which confer resistance to the antibiotic aureobasidin A, is necessary for inositol phosphorylceramide (IPC) synthase activity [9].
• Mutations in AUR1 had been shown previously to give resistance to the antifungal drug aureobasidin A, leading us to predict that the drug should inhibit IPC synthase activity [3].
• The AUR1 gene is necessary for addition of inositol phosphate to ceramide and has been identified as a target of several potent antifungal compounds [10].
• We propose that the mass mating method using spore suspensions in combination with dominant selective geneticin- and aureobasidin A-resistance markers is useful for the selection of hybrids from industrial homothallic yeasts [11].

Analytical, diagnostic and therapeutic context of AUR1

• We report the molecular cloning and characterization of the Aspergillus nidulans aurA gene, which is homologous to AUR1 [9].

References