CRISPR/Cas9-mediated ablation of elovl2 in Atlantic salmon (Salmo salar) inhibits elongation of polyunsaturated fatty acids and induces Srebp-1 and target genes


Atlantic salmon can synthesize polyunsaturated fatty acids (PUFAs), such as eicosapentaenoic acid (20:5n-3), arachidonic acid (20:4n-6) and docosahexaenoic acid (22:6n-3) via activities of very long chain fatty acyl elongases (elovls) and fatty acyl desaturases (fads), albeit to a limited degree. Understanding molecular mechanisms of PUFA biosynthesis and regulation is a pre-requisite for sustainable use of vegetable oils in aquafeeds as current sources of fish oils are unable to meet increasing demands for omega-3 PUFAs. By generating CRISPR-mediated elovl2 knockout, we have shown that elovl2 is crucial for multi-tissue synthesis of 22:6n-3 in vivo. Endogenously synthesized PUFAs are important for transcriptional regulation of lipogenic genes in Atlantic salmon. The elovl2 knockouts showed reduced levels of 22:6n-3 and accumulation of 20:5n-3 and docosapentaenoic acid (22:5n-3) in the liver, brain and white muscle, suggesting inhibition of elongation. Additionally, elovl2-knockout salmon showed accumulation of 20:4n-6 in brain and white muscle. The impaired synthesis of 22:6n-3 induced hepatic expression of sterol regulatory element binding protein-1 (srebp-1), fatty acid synthase-b, Δ6fad-a, Δ5fad and elovl5. Our study demonstrates key roles of elovl2 at two penultimate steps of PUFA synthesis in vivo and suggests Srebp-1 as a main regulator of endogenous PUFA synthesis in Atlantic salmon.


Projects: DigiSal



Date Published: 17th Dec 2018

Authors: Alex K. Datsomor, Nikola Zic, Keshuai Li, Rolf E. Olsen, Yang Jin, Jon Olav Vik, Rolf B. Evardsen, Fabian Grammes, Anna Wargelius, Per Winge

help Creator

Views: 162

Created: 17th Dec 2018 at 16:32

help Attributions


Related items

Powered by
Seek new full
Copyright © 2008 - 2019 The University of Manchester and HITS gGmbH