Isolation and Functional Characterisation of a fads2 in Rainbow Trout (Oncorhynchus mykiss) with Δ5 Desaturase Activity

• DOI: 10.1371/journal.pone.0150770
• Publication Date: 2016-03-04T18:38:37Z
• Authors: Noor Khalidah Abd...; Greta Carmona-Ant...; Óscar Monroig; Douglas R. Tocher; Giovanni M. Turchini; John A. Donald
• Keywords: FADS2; Fatty acid desaturase

Rainbow trout, Oncorhynchus mykiss, are intensively cultured globally. Understanding their requirement for long-chain polyunsaturated fatty acids (LC-PUFA) and the biochemistry of enzymes biosynthetic pathways required acid synthesis is important highly relevant in current aquaculture. Most gnathostome vertebrates have two desaturase (fads) genes with known functions LC-PUFA biosynthesis termed fads1 fads2. However, teleost fish exclusively fads2 genes. In rainbow a cDNA had been previously cloned found to encode an enzyme Δ6 activity. present study, second was from liver trout fads2b. The full-length mRNA contained 1578 nucleotides open reading frame 1365 that encoded 454 amino protein predicted molecular weight 52.48 kDa. Fads2b characteristic traits microsomal Fads family, including N-terminal cytochrome b5 domain containing heme-binding motif (HPPG), histidine boxes (HDXGH, HFQHH QIEHH) three transmembrane regions. fads2b expressed predominantly brain, liver, intestine pyloric caeca. Expression fasd2b yeast generated specifically convert eicosatetraenoic (20:4n-3) eicosapentaenoic (20:5n-3), therefore functioned as Δ5 desaturase. Therefore, proteins activities, respectively, which enable this species perform all desaturation steps C18 precursors.