title: Characterization of 2-enoyl thioester reductase from mammals. An ortholog of YBR026p/MRF1'p of the yeast mitochondrial fatty acid synthesis type II.
abstract: A data base search with YBR026c/MRF1', which encodes trans-2-enoyl thioester reductase of the intramitochondrial fatty acid synthesis (FAS) type II in yeast (Torkko, J. M., Koivuranta, K. T., Miinalainen, I. J., Yagi, A. I., Schmitz, W., Kastaniotis, A. J., Airenne, T. T., Gurvitz, A., and Hiltunen, K. J. (2001) Mol. Cell. Biol. 21, 6243-6253), revealed the clone AA393871 (HsNrbf-1, nuclear receptor binding factor 1) in human EST data bank. Expression of HsNrbf-1, tagged C-terminally with green fluorescent protein, in HeLa cells, resulted in a punctated fluorescence signal, superimposable with the MitoTracker Red dye. Wild-type polypeptide was immunoisolated from the extract of bovine heart mitochondria. Recombinant HsNrbf-1p reduces trans-2-enoyl-CoA to acyl-CoA with chain length from C6 to C16 in an NADPH-dependent manner with preference to medium chain length substrate. Furthermore, expression of HsNRBF-1 in the ybr026cDelta yeast strain restored mitochondrial respiratory function allowing growth on glycerol. These findings provide evidence that Nrbf-1ps act as a mitochondrial 2-enoyl thioester reductase, and mammalian cells may possess bacterial type fatty acid synthetase (FAS type II) in mitochondria, in addition to FAS type I in the cytoplasm.
authors.affiliation: Biocenter Oulu, Department of Biochemistry, University of Oulu, Finland.
authors.forename: Ilkka J
authors.initials: IJ
authors.lastname: Miinalainen
authors.forename: Zhi-Jun
authors.initials: ZJ
authors.lastname: Chen
authors.forename: Juha M
authors.initials: JM
authors.lastname: Torkko
authors.forename: Päivi L
authors.initials: PL
authors.lastname: Pirilä
authors.forename: Raija T
authors.initials: RT
authors.lastname: Sormunen
authors.forename: Ulrich
authors.initials: U
authors.lastname: Bergmann
authors.forename: Yong-Mei
authors.initials: YM
authors.lastname: Qin
authors.forename: J Kalervo
authors.initials: JK
authors.lastname: Hiltunen
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D017931:DNA Primers; D044943:Fatty Acid Desaturases / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008856:Microscopy, Fluorescence; D008929:Mitochondria, Heart / Q000201:enzymology; D008969:Molecular Sequence Data; D009247:NADH, NADPH Oxidoreductases; D044925:Oxidoreductases Acting on CH-CH Group Donors; D012441:Saccharomyces cerevisiae / Q000201:enzymology*; D017386:Sequence Homology, Amino Acid
chemical_list: D017931:DNA Primers; D044943:Fatty Acid Desaturases; D044925:Oxidoreductases Acting on CH-CH Group Donors; C434934:trans-2-enoyl-CoA reductase (NADPH); D009247:NADH, NADPH Oxidoreductases