Publications

• A stable yeast strain efficiently producing cholesterol instead of ergosterol is functional for tryptophan uptake, but not weak organic acid resistance.

  Souza C.M., Schwabe T.M., Pichler H., Ploier B., Leitner E., Guan X.L., Wenk M.R., Riezman I., Riezman H.

  Sterols are major lipids in eukaryotes and differ in their specific structure between species. Both cholesterol and ergosterol can form liquid ordered domains in artificial membranes. We reasoned that substituting the main sterol ergosterol by cholesterol in yeast should permit domain formation an ... >> More

  Sterols are major lipids in eukaryotes and differ in their specific structure between species. Both cholesterol and ergosterol can form liquid ordered domains in artificial membranes. We reasoned that substituting the main sterol ergosterol by cholesterol in yeast should permit domain formation and discriminate between physical and sterol structure-dependent functions. Using a cholesterol-producing yeast strain, we show that solute transporters for tryptophan and arginine are functional, whereas the export of weak organic acids via Pdr12p, a multi-drug resistance family member, is not. The latter reveals a sterol function that is probably dependent upon a precise sterol structure. We present a series of novel yeast strains with different sterol compositions as valuable tools to characterize sterol function and use them to refine the sterol requirements for Pdr12p. These strains will also be improved hosts for heterologous expression of sterol-dependent proteins and safe sources to obtain pure cholesterol and other sterols. << Less

  Metab Eng 13:555-569(2011) [PubMed] [EuropePMC]

  This publication is cited by 2 other entries.

• A comprehensive machine-readable view of the mammalian cholesterol biosynthesis pathway.

  Mazein A., Watterson S., Hsieh W.Y., Griffiths W.J., Ghazal P.

  Cholesterol biosynthesis serves as a central metabolic hub for numerous biological processes in health and disease. A detailed, integrative single-view description of how the cholesterol pathway is structured and how it interacts with other pathway systems is lacking in the existing literature. He ... >> More

  Cholesterol biosynthesis serves as a central metabolic hub for numerous biological processes in health and disease. A detailed, integrative single-view description of how the cholesterol pathway is structured and how it interacts with other pathway systems is lacking in the existing literature. Here we provide a systematic review of the existing literature and present a detailed pathway diagram that describes the cholesterol biosynthesis pathway (the mevalonate, the Kandutch-Russell and the Bloch pathway) and shunt pathway that leads to 24(S),25-epoxycholesterol synthesis. The diagram has been produced using the Systems Biology Graphical Notation (SBGN) and is available in the SBGN-ML format, a human readable and machine semantically parsable open community file format. << Less

  Biochem. Pharmacol. 86:56-66(2013) [PubMed] [EuropePMC]

  This publication is cited by 30 other entries.

• Delta7-sterol-C5-desaturase: molecular characterization and functional expression of wild-type and mutant alleles.

  Husselstein T., Schaller H., Gachotte D., Benveniste P.

  An Arabidopsis thaliana recessive monogenic mutant (ste1-1) presenting a deficiency of the delta7-sterol-C5(6)-desaturase step in the sterol pathway has been reported previously [12]. To further characterize ste1-1, Arabidopsis, Nicotiana tabacum and Homo sapiens cDNAs encoding delta7-sterol-C5(6) ... >> More

  An Arabidopsis thaliana recessive monogenic mutant (ste1-1) presenting a deficiency of the delta7-sterol-C5(6)-desaturase step in the sterol pathway has been reported previously [12]. To further characterize ste1-1, Arabidopsis, Nicotiana tabacum and Homo sapiens cDNAs encoding delta7-sterol-C5(6)-desaturases were isolated and identified on the basis of their ability to restore ergosterol synthesis in erg3, a yeast null mutant whose gene encoding the delta7-sterol-C5(6)-desaturase was disrupted. Overexpression of the Arabidopsis cDNA driven by a 35S promoter in transgenic ste1-1 plants led to full complementation of the mutant. This result demonstrates that STE1 was the impaired component in the desaturation system. Four independent reverse transcriptions of ste1-1 RNA followed by polymerase chain reactions (RT-PCRs), yielded a single product. Alignment of the wild-type ORF with the RT-PCR derived ste1-1 ORF revealed a single amino acid substitution: Thr-114 in the wild-type is changed to Ile in ste1-1. Expression in erg3 resulted in a 6-fold lowered efficiency of the ste1-1 ORF in complementing the yeast biosynthetic pathway when compared to the wild-type ORF. The presence of this mutation in the mutant ste1-1 genomic sequence (and no additional modification between ste1-1 and wild-type genes) demonstrates that the change of the Thr-114 to Ile is necessary and sufficient to create the leaky allele ste1-1. The occurrence of a hydroxylated amino acid (Thr or Ser) at the position corresponding to Thr-114 in the five delta7-sterol-C5(6)-desaturases identified so far suggests that this amino acid is important for normal enzymatic function. << Less

  Plant Mol. Biol. 39:891-906(1999) [PubMed] [EuropePMC]