The FADS2 catalyzes the first rate-limiting step in the long chain-polyunsaturated fatty acids
(LC-PUFAs) biosynthesis pathway by converting -linolenic acid and linoleic acid into
stearidonic acid and -linolenic acid via the -3 and -6 pathways respectively. In mammals,
PPAR and SREBP-1c have been implicated in the polyunsaturated fatty acids (PUFAs)
mediated transcriptional activation of FADS2 promoter. However, in zebrafish, not much is
known regarding the regulation of fads2 transcriptional regulation. Here, in this study, five
vectors containing different promoter regions were constructed in order to analyse putative
promoter activities. Through truncation analysis, it was found that the 1.2 kb promoter was able
to drive luciferase activity to an approximate 40-fold in HepG2 cells. Upon mutagenesis
analysis, three sites which are the putative NF-Y, SREBP and PPAR binding sites were found
to be essential in driving the promoter activity. Lastly, the 1.2 kb fads2 promoter was able to
direct EGFP expression specifically to the yolk syncytial layer (YSL) when transiently
expressed in microinjected zebrafish embryos.