Epigenetic Dysregulation of BRDT Gene in Testis Tissues of Infertile Men: Case-Control Study

OBJECTIVE: Bromodomain testis associated (BRDT), a testis-specific member of the Bromo- and Extra-Terrminal domain (BET) protein family, is involved in spermatogenesis and, more specifically, chromatin remodeling. In the post-meiotic spermatogenic cells, BRDT protein binds to the hyperacetylated histones and facilitates their replacement with transition proteins (TPs), particularly protamines, which are essential for chromatin condensation. The current research was conducted to assess the expression and epigenetic profile of BRDT in the testis tissues of infertile men. MATERIALS AND METHODS: In this case-control study, three groups were included: positive control group: obstructive azoospermia (OA, n=10), round spermatid maturation arrest group (SMA, n=10) and negative control group: sertoli cell- only syndrome (SCOS, n=10). Using quantitative real-time polymerase chain reaction (PCR), the expression profile of BRDT was generated. Also, ChIP-real time PCR was used to measure the following histone marks: H3K9ac, H3K9me3, H3K4me3, H3K27me3 on the promoter region of BRDT. RESULTS: Our data indicated that BRDT expression decreased in the SMA group in comparison with the positive control group and this finding is in line with the ChIP results obtained in this group. CONCLUSION: Based on these data, we postulate that BRDT gene has a vital role in the spermatogenesis and its decreased expression due to an aberrant epigenetic signaling might be associated with male infertility.