Previous studies showed that recombinant equine chorionic gonadotropin (rec-eCGβ/α) exhibits both folliclestimulating hormone (FSH) and luteinizing hormone (LH)-like activities in rat LHR- and FSHR-expressing cells. In this study, we analyzed signal transduction by eelFSHR and eelLHR upon stimulation with rec-eCGβ/α and native eCG. The cyclic adenosine monophosphate (cAMP) stimulation in CHO-K1 cells expressing eelLHR was determined upon exposure to different doses (0–1,450 ng/mL) of rec-eCGβ/α and native eCG. The EC50 values of rec-eCGβ/α and native eCG were 172.4 and 786.6 ng/mL, respectively. The activity of rec-eCGβ/α was higher than that of native eCG. However, signal transduction in the CHO PathHunter Parental cells expressing eelFSHR was not enhanced by stimulation with both agonist rec-eCGβ/α and native eCG. We concluded that rec-eCGβ/α and native eCG were completely active in cells expressing eelLHR, similar to the activity in the mammalian cells expressing LHRs. However, rec-eCGβ/α and native eCG did not invoke any signaling response in the cells expressing eelFSHR. These results suggest that eCG has a potent activity in cells expressing eelLHR. Thus, we also suggest that rec-eCGβ/α can induce eel maturation by administering gonadotropic reagents (LH), such as salmon pituitary extract.

ABSTRACT
INTRODUCTION
MATERIALS AND METHODS
RESULTS
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REFERENCES

• Munkhzaya Byambaragchaa(Animal Biotechnology, Graduate School of Future Convergence Technology, Dept. of Animal Life Science, Institute of Genetic Engineering, Hankyong National University)
• So-Yun Lee(Animal Biotechnology, Graduate School of Future Convergence Technology, Dept. of Animal Life Science, Institute of Genetic Engineering, Hankyong National University)
• Dae-Jung Kim(Aquaculture Research Division, National Institute of Fisher Science (NIFS))
• Myung-Hwa Kang(Dept. of Food Science and Nutrition, Hoseo University)
• Kwan-Sik Min(Animal Biotechnology, Graduate School of Future Convergence Technology, Dept. of Animal Life Science, Institute of Genetic Engineering, Hankyong National University) Corresponding Author