A novel family of longer chain length dolichols present in oleate-induced yeast Saccharomyces cerevisiae

The typical size of the yeast dolichol family ranges from 14 to 19 isoprene units D(14-19) with dolichol(16) bring the dominating species. Induction o f peroxisome proliferation by growing the cells in medium containing oleate as carbon source induces the: synthesis of an additional family of longer dolichols D(19-24) with D-21 being the most prominent. This phenomenon is a bolished in the peroxisome biogenesis deficient strain in which the PEX1 ge ne (encoding Pex1p peroxin) has been disrupted. The total amount of dolicho ls in pex1 Delta cells is lower than in the wild-type cells, as is the amou nt of phosphatidylcholine. Moreover, the levels of 3-hydroxy-3-methylglutar yl CoA reductase and farnesyl diphosphate synthase, two key enzymes in doli chol biosynthesis, are decreased in the absence of a functional PEX1 gene. The presence of longer dolichols in oleate-induced Saccharomyces cerevisiae cells, the absence of this additional family in peroxisome deficient cells , and a decrease of the total amount of dolichols in these cells indicate t he involvement of peroxisomes in the biosynthesis of dolichols in this orga nism. (C) 2001 Societe francaise de biochimie et biologic moleculaire/Editi ons scientifiques et medicales Elsevier SAS. All rights reserved.