Department of Urology, Pediatric Urology and Andrology, Rudolf Buchheim-Strasse 7, Justus Liebig University, 35385 Giessen, Germany.
Reproduction. 2010 Sep;140(3):435-43. doi: 10.1530/REP-10-0139. Epub 2010 Jun 10.
As histone modifications have been suggested to be involved in the regulation of gene expression after fertilisation, the present study aimed to analyze the interaction between the bromodomain testis-specific (BRDT) gene and differentially modified histones in human spermatozoa. The BRDT transcript level was studied to identify possible correlations between epigenetic changes, mRNA level and subfertility associated with impaired sperm chromatin condensation. Chromatin immunoprecipitation (ChIP) was performed with ejaculates from fertile and subfertile men using antibodies against specifically acetylated and methylated histone H3. Immunoprecipitated DNA was analysed by real-time quantitative PCR with primer pairs for BRDT. The BRDT mRNA level was screened by real-time RT-PCR. ChIP assay revealed co-localisation of acetylated and methylated histones within promoter and exon regions of the BRDT gene in fertile men. Interestingly, reduced binding of investigated modified histone modifications was observed in the BRDT promoter of subfertile patients. Different mRNA levels of BRDT have been detected in a group of infertile patients, as well as in fertile men. Enrichment of methylated histones within the BRDT promoter of fertile sperm suggests that this epigenetic mark may cause repression of BRDT after fertilisation, and may be changed in infertile patients. Our data suggest that reduced histone methylation in the promoter of BRDT may be associated with increased transcript levels in subfertile patients.
由于组蛋白修饰被认为参与受精后基因表达的调控，本研究旨在分析溴结构域睾丸特异性（BRDT）基因与人类精子中差异修饰组蛋白之间的相互作用。研究了 BRDT 转录本水平，以确定表观遗传变化、mRNA 水平与与精子染色质凝聚受损相关的亚生育力之间的可能相关性。使用针对特定乙酰化和甲基化组蛋白 H3 的抗体，对来自生育力正常和生育力低下男性的精液进行染色质免疫沉淀（ChIP）。通过实时定量 PCR 用 BRDT 的引物对分析免疫沉淀的 DNA。通过实时 RT-PCR 筛选 BRDT mRNA 水平。ChIP 分析显示，在生育力正常男性的 BRDT 基因启动子和外显子区域中，乙酰化和甲基化组蛋白存在共定位。有趣的是，在亚生育力患者的 BRDT 启动子中观察到研究的修饰组蛋白结合减少。在一组不育患者以及生育力正常的男性中，检测到 BRDT 的不同 mRNA 水平。BRDT 启动子中甲基化组蛋白的富集表明，这种表观遗传标记可能在受精后导致 BRDT 的抑制，并且在不育患者中可能发生变化。我们的数据表明，BRDT 启动子中组蛋白甲基化减少可能与亚生育力患者的转录本水平升高有关。
