New insights into the biological activity and secretion properties of a polypeptide derived from tilapia somatotropin.

In a previous study, we unexpectedly found that tilapia growth hormone (tiGH) secreted to the culture media by transformed cells of the yeast Pichia pastoris lacks 46 amino acids from the C-terminal end. In the present study, we cloned the exact fragment that code for this truncated variant and demonstrated its growth promoting activity in goldfish when it's administered by immersion bath. Furthermore, a better characterization of this polypeptide was performed.