The Function Of Propionyl Oligopeptidase In Murine Corpus Luteum

Objectives:Prolyl oligopeptidase(POP)is a serine protease with specific hydrolytic peptide chain of proline residue carboxyl terminated peptide in polypeptide chain.Studies showed that POP was highly expressed in the ovary of mouse,however,the exact function of POP in ovary is still unclear.In the study,we will examine the expression of POP in corpus luteum and explore the function and possible mechanism of POP in luteal cells.Methods:Immunohistochemistry and Western-blot was used to examine the spatiotemporal distribution of POP in ovaries.Primary luteal cells,were cultured in vitro and treated with POP overxpression plasmid and POP inhibitor,KYP-2047.The influence of POP on cell viability was examined through CCK assay.The changes of progesterone and estradiol were detected by radioimmunoassay.Quantitative PCR and Western-blotting was employed to examine the expression of steroidogenic enzymes and possible signaling pathways.Results:Immunohistochemistry showed that POP was highly expressed in murine corpus luteum.POP had no significant effect on luteal cell viability.Overexpression of POP promoted progesterone secretion,but had no significant effect on estradiol.The secretion of progesterone and estradiol were decreased after KYP-2047 treatment.Further study found that POP affected the expression of key enzymes of the steroid hormone synthesis,including CYP11A1,3?-HSD and StAR.SF1 is a key transcription factor for regulating the synthesis of progesterone.We also found that the expression of SF1 was increased after POP overexpression,and the expression of SF1 was decreased after KYP-2047 treatment.Conclusion:1.POP is highly expressed in murine corpus leteum.2.POP promotes the synthesis of progesterone in murine luteal cells.3.POP regulates the secretion of progesterone by stimulating the expression of CYP11A1,3?-HSD and StAR in luteal cells,and SF1 participates in this process.