Production of biologically active recombinant goose FSH in a single chain form with a CTP linker sequence

FSH is a glycoprotein hormone secreted by the pituitary gland that is essential for gonadal development and reproductive function. In avian reproduction study, especially in avian reproduction hormone study, it is hindered by the lack of biologically active FSH. In order to overcome this shortcoming, we prepared recombinant goose FSH as a single chain molecule and tested its biological activities in the present study. Coding sequences for mature peptides of goose FSH α and β subunits were amplified from goose pituitary cDNA. A chimeric gene containing α and β subunit sequences linked by the hCG carboxyl terminal peptide coding sequence was constructed. The recombinant gene was inserted into the pcDNA3.1-Fc eukaryotic expression vector to form pcDNA-Fc-gFSHβ-CTP-α and then transfected into 293-F cells. A recombinant, single chain goose FSH was expressed and verified by SDS-PAGE and western blot analysis, and was purified using Protein A agarose affinity and gel filtration chromatography. Biological activity analysis results showed that the recombinant, chimeric goose FSH possesses the function of stimulating estradiol secretion and cell proliferation, in cultured chicken granulosa cells. These results indicated that bioactive, recombinant goose FSH has been successfully prepared in vitro. The recombinant goose FSH will have the potential of being used as a research tool for studying avian reproductive activities, and as a standard for developing avian FSH bioassays.