title: Evidence for a novel pathway for the targeting of a Saccharomyces cerevisiae peroxisomal protein belonging to the isomerase/hydratase family.
abstract: We, and others, have identified a novel Saccharomyces cerevisiae peroxisomal protein that belongs to the isomerase/hydratase family. The protein, named Dci1p, shares 50% identity with Eci1p, a delta(3)-cis-delta(2)-trans-enoyl-CoA isomerase that acts as an auxiliary enzyme in the beta-oxidation of unsaturated fatty acids. Both of these proteins are localized to peroxisomes, and both contain motifs at their amino- and carboxyl termini that resemble peroxisome targeting signals (PTS) 1 and 2. However, we demonstrate that the putative type 1 signaling motif is not required for the peroxisomal localization of either of these proteins. Furthermore, the correct targeting of Eci1p and Dci1p occurs in the absence of the receptors for the type 1 or type 2 peroxisome targeting pathway. Together, these data suggest a novel mechanism for the intracellular targeting of these peroxisomal proteins.
authors.affiliation: Department of Cell Biology, Mount Sinai School of Medicine, New York, NY 10029, USA.
authors.forename: I V
authors.initials: IV
authors.lastname: Karpichev
authors.forename: G M
authors.initials: GM
authors.lastname: Small
mesh_terms: D000595:Amino Acid Sequence; D001692:Biological Transport; D019748:Carbon-Carbon Double Bond Isomerases / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins; D064006:Dodecenoyl-CoA Isomerase; D004790:Enzyme Induction / Q000187:drug effects; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D015966:Gene Expression Regulation, Fungal / Q000187:drug effects; D018390:Gene Targeting; D008565:Membrane Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D019301:Oleic Acid / Q000494:pharmacology; D010446:Peptide Fragments / Q000502:physiology; D000074437:Peroxisomal Targeting Signal 2 Receptor; D000074435:Peroxisome-Targeting Signal 1 Receptor; D020675:Peroxisomes / Q000378:metabolism*; D018160:Receptors, Cytoplasmic and Nuclear / Q000172:deficiency / Q000235:genetics / Q000502:physiology; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000502:physiology; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D008565:Membrane Proteins; C120764:OAF1 protein, S cerevisiae; C100530:PIP2 protein, S cerevisiae; D010446:Peptide Fragments; D000074437:Peroxisomal Targeting Signal 2 Receptor; D000074435:Peroxisome-Targeting Signal 1 Receptor; D018160:Receptors, Cytoplasmic and Nuclear; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D019301:Oleic Acid; D019748:Carbon-Carbon Double Bond Isomerases; C120150:DCI1 protein, S cerevisiae; D064006:Dodecenoyl-CoA Isomerase