Molecular cloning, identification, and expression analysis of Pyy and its effect on mechanisms regulating appetite in Spotted scat, Scatophagus argus

The peptide YY (Pyy) is a member of the Neuropeptide Y family of peptides known to play anorexigenic roles in the regulation of feed intake in several fishes. In this study, to examine the role of Pyy in the spotted scat (Scatophagus argus), the peptide was cloned from this fish for the first time. The peptide is made from a 294-bp open reading frame with a 97-amino-acid sequence that is highly conserved when compared to other organisms. The pyy gene is expressed widely throughout the spotted scat, with the highest levels in the intestine and muscle tissue. According to our pre-and post-prandial experiments, feeding has a minimal short-term effect on pyy mRNA levels. In comparison to fish that were refed on the 8th day after 7 days of starvation, pyy mRNA levels in the hypothalamus were considerably higher after 7 days of feeding. Results from this study also identified a local interaction between Pyy and some appetite-regulating peptides in spotted scat. We aimed to build a solid foundation for future research into feed intake regulation of the spotted scat, as this is one of the most cultured species.