Abstract
African catfish (Clarias gariepinus) is one of the economically valuable aquaculture fish species in Indonesia. This research was aimed to produce F0 transgenic catfish carrying masou salmon Δ6-desaturase-like (OmΔ6FAD) gene. The Δ6-desaturase enzyme is involved in highly unsaturated fatty acid biosynthesis. Transgenic catfish was produced by sperm-mediated gene transfer using electroporation method. In this study, as the first step, sperms were electroporated with three different OmΔ6FAD concentration (25, 50, and 100 µg mL-1) to have the highest sperm viability after electroporation (125 V/cm, pulse frequency 5 times, pulse length 30 millisecond, pulse interval 0.1 second). The highest sperm viability and sperm carrying OmΔ6FAD were obtain at 100 µg mL-1. This concentration was then used to produce F0 transgenic catfish in the second step. Sperm motility, sperm viability, fertilization rate, hatching rate, and larval survival at 14 days after hatching were the same as the controls (p>0.05). Genomic DNA was extracted from caudal fin and then used as template to identify transgenic F0 by PCR method using specific primer for OmΔ6FAD gene. The PCR result showed that 53.84% of F0 carried OmΔ6FAD gene. The result of fatty acid analysis showed that EPA and DHA contents of F0 transgenic fish and non-transgenic fish were similar. Keywords: catfish, Δ6-desaturase-like gene, fatty acids, electroporation
Highlights
Long chain unsaturated fatty acids, Eicosapentaenoic acid (EPA; C20: 5n-3) and Docosahexaenoicacid (DHA; C22: 6n-3) have important nutrional benefits in humans(Simopoulos, 1991; Lauritzen et al, 2001), and are generally found in both freshwater and marine fish species
EPA and DHA levels are higher in marine fish compared to the freshwater one, as the former species selectively accumulate EPA and DHA from natural food.For instance, EPA and DHA contents of Atlantic salmonranged between 13.1-15.2% and 6.6-7.9%, respectively (Blancheta et al, 2005), while those of catfish were just 0.68% and 0.43%, respectively (Gunawan et al, 2014)
The initial DNA concentration was determined using a genequant (Pharmacia Biotech genequant)and three DNA concentrated solutions were made for gene transfer i.e. 25, 50 dan 100 μg mL-1
Summary
Long chain unsaturated fatty acids, Eicosapentaenoic acid (EPA; C20: 5n-3) and Docosahexaenoicacid (DHA; C22: 6n-3) have important nutrional benefits in humans(Simopoulos, 1991; Lauritzen et al, 2001), and are generally found in both freshwater and marine fish species. Freshwater fish have the ability to synthesize EPA and DHA, since they possess all the enzyme coding genes that are involved infatty acids biosynthesis. Marine fish do not possess fatty acids synthesizing enzymes. Δ6-desaturase isa fatty acid metabolic enzyme that is involved inEPA and DHA biosynthesis. This enzyme uses α-linolenic acid (ALA, C18:3n-3) as a substrate and allows the insertion of a double bond to produce octadecatrienoic acid (OTA, C18: 4n-3). The OTA is converted by elongase to produce eicosatetraenoic acid (ETA, C20: 4n-3), a substrate of Δ5-desaturasion in EPA synthesis. The same Δ6-desaturase metabolizes the fatty acid C24:5n-3 to C24:6n-3, which is retro-converted by peroxisomes via β-oxidation to yield DHA (Sprecher, 2000)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
