| Title: | "An abundant acyl-CoA (Delta9) desaturase transcript in pheromone glands of the cabbage moth, Mamestra brassicae, encodes a catalytically inactive protein" |
| Author(s): | Park HY; Kim MS; Paek A; Jeong SE; Knipple DC; |
| Address: | "Department of Biological Sciences, Hannam University, 133 Ojung-Dong, Daedeok-Gu, Daejeon 306-791, South Korea" |
| DOI: | 10.1016/j.ibmb.2008.02.001 |
| ISSN/ISBN: | 0965-1748 (Print) 0965-1748 (Linking) |
| Abstract: | "The principal sex pheromone component produced by females of the cabbage moth, Mamestra brassicae, is derived from the monounsaturated fatty acid, Z11-16:1, whereas two additional trace components are derived from E11-16:1 and Z9-16:1. This report presents the isolation and analysis of cDNAs encoding pheromone gland-specific acyl-CoA desaturases implicated in the production of these unsaturated fatty acids (UFAs). Comparisons of the encoded amino acid sequences of four cDNA fragments isolated by degenerate PCR from cabbage moth pheromone glands established their orthology with previously characterized noctuid desaturases as follows: MbraLPAQ, belonging to the pheromone gland-specific LPAQ desaturase lineage having Delta11 regioselectivity, MbraKPSE-a and MbraKPSE-b, belonging to the pheromone gland-specific KPSE desaturase lineage having Delta9 regioselectivity and a substrate preference for palmitic acid (16:0) over oleic acid (18:0), and MbraNPVE, belonging to the NPVE desaturase lineage having Delta9 regioselectivity and a substrate preference 18:0>16:0. Full-length cDNAs corresponding to the two most abundantly expressed pheromone gland-specific desaturase transcripts, MbraLPAQ and MbraKPSE-b, were isolated and assayed for their ability to genetically complement the UFA auxotrophy of a desaturase-deficient ole1 strain of Saccharomyces cerevisiae. The MbraLPAQ desaturase restored UFA prototrophy and GC-MS analysis identified Z11-16:1 and Z11-18:1 as the predominant UFAs produced. Surprisingly, MbraKPSE-b failed to complement the ole1 mutation, although it shares >98% amino acid sequence similarity with other noctuid KPSE desaturases that do. Site-directed mutagenesis of either or both of two nonconservative amino acid substitutions restored functionality to the MbraKPSE-b protein, although GC-MS analysis revealed that neither reversion resulted in the characteristic KPSE substrate preference for 16:0" |
| Keywords: | "Amino Acid Sequence Animals DNA, Complementary Female Molecular Sequence Data Moths/*enzymology/genetics Mutagenesis, Site-Directed Mutation, Missense Pheromones/biosynthesis Polymerase Chain Reaction Sequence Analysis, DNA Stearoyl-CoA Desaturase/genetic;" |
| Notes: | "MedlinePark, Hee Yun Kim, Myung Sook Paek, Aron Jeong, Seong Eun Knipple, Douglas C eng Research Support, Non-U.S. Gov't England 2008/04/15 Insect Biochem Mol Biol. 2008 May; 38(5):581-95. doi: 10.1016/j.ibmb.2008.02.001. Epub 2008 Feb 16" |
