Histone Methylation in the CYP11A1 Gene Promoter in the Follicular Granulosa Cells Extracted from the Women Referring to theFertility Treatment Clinic in Tabriz, Iran

Infertility is defind as the inability to conceive after one year of regular unprotected sexual intercourse by a couple. Female infertility can have different causes that all factors can in somehow be influenced by genetic factors. Studies have shown that epigenetic changes play an important role in fetal development, oogenesis and spermatogenesis. During the growth of oocyte, follicular cells make a multilayer coating of granulosa cells. Granulosa cells are affected by gonadotropin hormones. The CYP11A1 gene is one of the genes involved in the production of steroid hormones in luteinized granulosa cells. The CYP11A1 enzyme in the progesterone prodaction path way leads to the conversion of cholesterol to pregnenolon. Progesterone is an important steroid hormone that plays an important role in fertility and pregnancy. Histone modifications help to express the CYP11A1 gene. Trimethylation of Lysine 4 on histone H3 (H3K4me3) works to active transcription in the CYP11A1 promoterIn the present study, the level of methylation H3K4me3 in regulation area of CYP11A1 gene in granulosa cells collected from the women with infertility problem and also from fertile women giving oocyte was investigated in Tabriz Jihad Daneshgahi infertilization center. To do this, the Chromatin Immunoprecipitation and then Real-Time PCR were used to investigate the level of methylation.According to the results of the present study, the level of methylation H3K4me3 in the regulating area of CYP11A1 gene in the given infertile people doesn’t show significant difference in comparision with control group and no significant relationship was observed between methylation of histone in CYP11A1 promoter and number of follicles and oocyte.It is suggested that epigenetic changes in regulating area of CYP11A1 gene are not involved in the number of follicle and oocytes.      

Keywords:

Granulosa cells , Histone methylation , steroidogenesis , CYP11A1 gene.