Liu Shuli, Chen Siqian, Cai Wentao, Yin Hongwei, Liu Aoxing, Li Yanhua, Liu George E, Wang Yachun, Yu Ying, Zhang Shengli
Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture & National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, 2rd, Yuanmingyuan West Road, Beijing 100193, China.
Beijing Dairy Cattle Center, Qinghe South Town, Beijing 100085, China.
Epigenomes. 2019 Sep 26;3(4):21. doi: 10.3390/epigenomes3040021.
Semen quality is critical for fertility. However, it is easily influenced by environmental factors and can induce subfertility in the next generations. Here, we aimed to assess the impacts of differentially methylated regions and genes on semen quality and offspring fertility. A specific pair of monozygotic (MZ) twin artificial insemination (AI) Holstein bulls with moderately different sperm qualities (Bull1 > Bull2) was used in the study, and each twin bull had produced ~6000 recorded daughters nationwide in China. Using whole genome bisulfite sequencing, we profiled the landscape of the twin bulls' sperm methylomes, and we observed markedly higher sperm methylation levels in Bull1 than in Bull2. Furthermore, we found 528 differentially methylated regions (DMR) between the MZ twin bulls, which spanned or overlapped with 309 differentially methylated genes (DMG). These DMG were particularly associated with embryo development, organ development, reproduction, and the nervous system. Several DMG were also shown to be differentially expressed in the sperm cells. Moreover, the significant differences in DNA methylation on gene between the MZ twin bulls were confirmed at three different age points. Our results provided new insights into the impacts of AI bull sperm methylomes on offspring fertility.
精液质量对生育能力至关重要。然而，它很容易受到环境因素的影响，并可能导致下一代的生育能力低下。在此，我们旨在评估差异甲基化区域和基因对精液质量和后代生育能力的影响。本研究使用了一对具有中等不同精子质量（公牛1>公牛2）的同卵（MZ）双胞胎人工授精（AI）荷斯坦公牛，每头双胞胎公牛在中国全国范围内都有大约6000头有记录的女儿。通过全基因组亚硫酸氢盐测序，我们描绘了双胞胎公牛精子甲基化组的图谱，并且我们观察到公牛1的精子甲基化水平明显高于公牛2。此外，我们在MZ双胞胎公牛之间发现了528个差异甲基化区域（DMR），这些区域跨越或重叠了309个差异甲基化基因（DMG）。这些DMG特别与胚胎发育、器官发育、生殖和神经系统相关。还显示几个DMG在精子细胞中差异表达。此外，在三个不同年龄点证实了MZ双胞胎公牛之间基因上DNA甲基化的显著差异。我们的结果为AI公牛精子甲基化组对后代生育能力的影响提供了新的见解。
