title: Regulation of peroxisome size and number by fatty acid beta -oxidation in the yeast yarrowia lipolytica.
abstract: The Yarrowia lipolytica MFE2 gene encodes peroxisomal beta-oxidation multifunctional enzyme type 2 (MFE2). MFE2 is peroxisomal in a wild-type strain but is cytosolic in a strain lacking the peroxisomal targeting signal-1 (PTS1) receptor. MFE2 has a PTS1, Ala-Lys-Leu, that is essential for targeting to peroxisomes. MFE2 lacking a PTS1 can apparently oligomerize with full-length MFE2 to enable targetting to peroxisomes. Peroxisomes of an oleic acid-induced MFE2 deletion strain, mfe2-KO, are larger and more abundant than those of the wild-type strain. Under growth conditions not requiring peroxisomes, peroxisomes of mfe2-KO are larger but less abundant than those of the wild-type strain, suggesting a role for MFE2 in the regulation of peroxisome size and number. A nonfunctional version of MFE2 did not restore normal peroxisome morphology to mfe2-KO cells, indicating that their phenotype is not due to the absence of MFE2. mfe2-KO cells contain higher amounts of beta-oxidation enzymes than do wild-type cells. We also show that increasing the level of the beta-oxidation enzyme thiolase results in enlarged peroxisomes. Our results implicate peroxisomal beta-oxidation in the control of peroxisome size and number in yeast.
authors.affiliation: Department of Cell Biology, University of Alberta, Edmonton, Alberta T6G 2H7, Canada.
authors.forename: J J
authors.initials: JJ
authors.lastname: Smith
authors.forename: T W
authors.initials: TW
authors.lastname: Brown
authors.forename: G A
authors.initials: GA
authors.lastname: Eitzen
authors.forename: R A
authors.initials: RA
authors.lastname: Rachubinski
mesh_terms: D015094:3-Hydroxyacyl CoA Dehydrogenases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D000101:Acetyl-CoA C-Acetyltransferase / Q000378:metabolism; D000595:Amino Acid Sequence; D001483:Base Sequence; D048429:Cell Size; D003600:Cytosol / Q000378:metabolism; D004746:Enoyl-CoA Hydratase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D000939:Epitopes / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism*; D006801:Humans; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D016297:Mutagenesis, Site-Directed; D019301:Oleic Acid / Q000494:pharmacology; D010100:Oxygen / Q000378:metabolism*; D020675:Peroxisomes / Q000378:metabolism* / Q000648:ultrastructure; D010957:Plasmids; D011401:Promoter Regions, Genetic; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D004718:Saccharomycetales / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid
chemical_list: D000939:Epitopes; D005227:Fatty Acids; D009097:Multienzyme Complexes; D016271:Proto-Oncogene Proteins c-myc; D011994:Recombinant Proteins; D019301:Oleic Acid; D015094:3-Hydroxyacyl CoA Dehydrogenases; D000101:Acetyl-CoA C-Acetyltransferase; D004746:Enoyl-CoA Hydratase; D010100:Oxygen