Please use this identifier to cite or link to this item:
Full metadata record
DC FieldValueLanguage
dc.contributor.authorZheng, Xiaozhongen_UK
dc.contributor.authorTocher, Douglas Ren_UK
dc.contributor.authorDickson, Cathrynen_UK
dc.contributor.authorBell, J Gordonen_UK
dc.contributor.authorTeale, Alan Jen_UK
dc.description.abstractFish are an important dietary source of the long-chain C20 and C22 highly unsaturated fatty acids (HUFA), arachidonate (20:4n-6), eicosapentaenoate (20:5n-3) and docosahexaenoate (22:6n-3), that are crucial to the health of higher vertebrates and that can be beneficial in human diets. Δ5 and Δ6 fatty acid desaturases, and fatty acid elongases are critical enzymes in the biosynthetic pathways of HUFA from shorter chain C18 polyunsaturated fatty acids (PUFA) such as linoleic (18:2n-6) and α-linolenic (18:3n-3) acids. Recently, full-length cDNAs for fatty acid desaturase and elongase enzymes have been cloned from Atlantic salmon. Functional characterisation of the desaturase revealed n-3 Δ5 desaturase activity, whereas the elongase had broad substrate specificity for PUFA with a range of chain lengths from C18 to C22. The study described here was primarily focused on the nutritional regulation of genes involved in the HUFA biosynthetic pathway in Atlantic salmon. A feeding trial was performed whereby salmon smolts in seawater pens were fed for 40 weeks on five different diets. The diets consisted of a control diet containing fish oil (FO) and four diets in which the FO was replaced in a graded manner by linseed oil (LO). Specifically, in terms of added oils, the five diets were 100% FO (FO), 100%LO (LO100) and FO/LO in ratios of 3:1 (LO25), 1:1 (LO50) and 1:3 (LO75). Fish were sampled at 20 and 40 weeks, and samples of liver were collected for lipid analyses and total RNA extraction. Hepatocytes were also prepared and the activity of the HUFA biosynthetic pathway determined. Expression of fatty acid desaturase and elongase genes was determined by quantitative real time PCR and the ratio of the copy number of the targeted gene against that of β-actin was calculated. The results showed that after 20 weeks of feeding, desaturase and elongase gene expression in liver was increased in a graded manner by increasing dietary LO. Expression of both genes was positively and negatively correlated with dietary 18:3n-3 and n-3 HUFA, respectively. By 40 weeks of feeding, expression of neither gene showed the same degree of correlation with dietary fatty acid composition. In contrast, activity of the HUFA biosynthetic pathway, which showed some association with diet at 20 weeks, was positively and significantly correlated with dietary LO after 40 weeks of feeding. Elongation activity reflected the overall activity of the HUFA biosynthetic pathway to a greater degree than Δ5 desaturation activity. The possible mechanisms underlying the observed results and the regulation of the HUFA biosynthetic pathway are discussed.en_UK
dc.relationZheng X, Tocher DR, Dickson C, Bell JG & Teale AJ (2004) Effects of diets containing vegetable oil on expression of genes involved in highly unsaturated fatty acid biosynthesis in liver of Atlantic salmon (Salmo salar). Aquaculture, 236 (41000), pp. 467-483.;
dc.rightsPublished in Aquaculture by Elsevier. Aquaculture, Volume 236, Issues 1-4, June 2004, pp. 467 - 483; This is the peer reviewed version of this article.; NOTICE: this is the author’s version of a work that was accepted for publication in Aquaculture. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Aquaculture, VOL 236, ISSUE 1-4, June 2004. DOI 10.1016/j.aquaculture.2004.02.003en_UK
dc.subjectAtlantic salmonen_UK
dc.subjectSalmo salaren_UK
dc.subjectFish oilen_UK
dc.subjectVegetable oilen_UK
dc.subjectLinseed oilen_UK
dc.subjectLipid metabolismen_UK
dc.subjectFatty acid metabolismen_UK
dc.subjectPolyunsaturated fatty acidsen_UK
dc.subjectGene expressionen_UK
dc.subjectAtlantic salmonen_UK
dc.subjectFishes Nutritionen_UK
dc.subjectFishes Qualityen_UK
dc.subjectFishes Feeding and feedsen_UK
dc.subjectVegetable oilsen_UK
dc.titleEffects of diets containing vegetable oil on expression of genes involved in highly unsaturated fatty acid biosynthesis in liver of Atlantic salmon (Salmo salar)en_UK
dc.typeJournal Articleen_UK
dc.type.statusAM - Accepted Manuscripten_UK
dc.contributor.affiliationInstitute of Aquacultureen_UK
dc.contributor.affiliationInstitute of Aquacultureen_UK
dc.contributor.affiliationInstitute of Aquacultureen_UK
dc.contributor.affiliationInstitute of Aquacultureen_UK
dc.contributor.affiliationUniversity of Stirlingen_UK
rioxxterms.typeJournal Article/Reviewen_UK
local.rioxx.authorZheng, Xiaozhong|en_UK
local.rioxx.authorTocher, Douglas R|0000-0002-8603-9410en_UK
local.rioxx.authorDickson, Cathryn|en_UK
local.rioxx.authorBell, J Gordon|en_UK
local.rioxx.authorTeale, Alan J|en_UK
local.rioxx.projectInternal Project|University of Stirling|
local.rioxx.filenameRAFOA 1 HUFA synth (final).pdfen_UK
Appears in Collections:Aquaculture Journal Articles

Files in This Item:
File Description SizeFormat 
RAFOA 1 HUFA synth (final).pdfFulltext - Accepted Version378.07 kBAdobe PDFView/Open

This item is protected by original copyright

Items in the Repository are protected by copyright, with all rights reserved, unless otherwise indicated.

The metadata of the records in the Repository are available under the CC0 public domain dedication: No Rights Reserved

If you believe that any material held in STORRE infringes copyright, please contact providing details and we will remove the Work from public display in STORRE and investigate your claim.