Expression Of Progesterone Synthesis Related Genes In Lueyang Chicken

Lueyang chicken is a famous local breed in Shaanxi Province.In recent years,there was a rapid increase demand for Lueyang chicken in market.however,the annual egg production of Lueyang Chicken is only about 110 eggs,which obviously cannot meet the production targets of farmers to expand scale in a short time and seriously affect their economic benefits.Progesterone is an important component of progesterone and plays an important role in the development of ovaries and follicles in female birds.The STAR,CYP11A1and HSD3B1 are the key genes involved in progesterone synthesis,but few studies have been reported in Lueyang chicken.In this experiment,Lueyang chicken was used as experimental group and Jinghong No.1 laying hen as the control group.The content of progesterone in ovarian tissue was detected by ELISA.The expression of STAR,CYP11A1 and HSD3B1 m RNA were detected by q PCR.The promoter sequence and regulatory elements of STAR and CYP11A1were analyzed by bioinformatic softs.The relationship between the transcriptional regulation of STAR and CYP11A1 genes and progesterone synthesis was investigated at the molecular level.The results of this research as following:1. Compared with Jinghong No.1 layer hen,the progesterone content of ovary tissue of Lueyang chicken was significantly lower than Jinghong No.1 layer hen（P<0.05）;The expression level of STAR gene m RNA in ovary tissue of Lueyang chicken was significantly higher than that of Jinghong No.1 layer（P<0.01）and the m RNA expression level of CYP11A1 gene was significantly higher than that of Jinghong 1 layer hen（P<0.05）.2. The promoter regions of STAR and CYP11A1 were successfully amplified.Three core promoter regions were predicted in the STAR promoter region.In the CYP11A1 promoter region,two core promoter regions and one Cp G island were predicted.The binding site of transcription factor c/EBPβis predicted in the promoter region of CYP11A1 gene.3. The dual luciferase reporter vector for CYP11A1 gene promoter（LY-p GL₃-CYP11A1-Promoter、JH-p GL₃-CYP11A1-Promoter）and transcription factor c/EBPβoverexpression vector（pc DNA3.1（+）-c/EBPβ-CDS）were constructed.After co-transfected the vectors to293T cells,the transcriptional activity of the CYP11A1 promoter region of Lueyang chicken was significantly increased（P<0.01）.Overexpression of c/EBPβsignificantly increased CYP11A1 transcription level in Lueyang Chicken（P<0.01）.c/EBPβbinds to the promoter region of CYP11A1 in Lueyang Chicken and enhances the expression of CYP11A1.In summary,this study describes the expression levels of STAR and CYP11A1 genes in the ovary tissues of Lueyang chickens and the regulatory mechanism of CYP11A1 genes during the synthesis of progesterone.It was also found that in the ovary tissue of Lueyang chicken,the transcription factor c/EBPβpositively regulates the expression of CYP11A1gene.It is helpful to provide a theoretical basis for genetic improvement of the reproductive performance of Lueyang chickens.