Kern Chandlar, Liu Wan-Sheng
Department of Animal Science, Center for Reproductive Biology and Health (CRBH), College of Agricultural Sciences, The Pennsylvania State University, University Park, PA, 16802, USA.
Cell Tissue Res. 2025 May 14. doi: 10.1007/s00441-025-03975-1.
Infertility and subfertility are significant reproductive challenges in cattle, often linked to genetic factors. Among these genetic factors, the bovine Y-linked gene family, PRAMEY, has emerged as a candidate due to its involvement in germ cell formation, fertilization, and embryonic development. This study investigates PRAMEY's role in sperm-egg binding, acrosome integrity, and epigenetic modifications during fertilization and early embryogenesis. Using IVF with bovine spermatozoa treated with either PRAMEY antibody (ab) or rabbit IgG control, we assessed sperm-egg binding and acrosome integrity at 2, 4, and 6 h post-fertilization (hpf). PRAMEY ab treatment doubled sperm binding per oocyte across all time points, with a significant increase at 6 hpf (P ≤ 0.05), although no differences in acrosome integrity were observed (P > 0.05). To explore PRAMEY's role in epigenetic regulation, we analyzed DNA (5-methylcytosine (5-mC)) and histone (H3K9me3 and H3K27me3) methylation in zygotes and embryos using immunofluorescent staining techniques. Zygotes derived from PRAMEY ab-treated spermatozoa showed significantly reduced DNA methylation in paternal pronuclei at 10 hpf and maternal pronuclei at 25 hpf (P ≤ 0.01). Histone methylation analysis revealed no significant differences in H3K9me3 methylation between groups, but H3K27me3 methylation was significantly lower in embryos produced using PRAMEY ab-treated spermatozoa at the 8-cell and morula stages (P ≤ 0.05). In summary, PRAMEY inhibition enhances sperm-egg binding and influences DNA and histone methylation dynamics in bovine embryos, underscoring its potential role in fertilization and early embryonic epigenetic regulation.
不育和亚生育能力是牛繁殖过程中的重大挑战，通常与遗传因素有关。在这些遗传因素中，牛Y染色体连锁基因家族PRAMEY因其参与生殖细胞形成、受精和胚胎发育而成为候选基因。本研究调查了PRAMEY在受精和早期胚胎发生过程中对精卵结合、顶体完整性和表观遗传修饰的作用。使用经PRAMEY抗体（ab）或兔IgG对照处理的牛精子进行体外受精，我们在受精后2、4和6小时（hpf）评估了精卵结合和顶体完整性。PRAMEY ab处理使所有时间点每个卵母细胞的精子结合增加了一倍，在6 hpf时显著增加（P≤0.05），尽管未观察到顶体完整性有差异（P>0.05）。为了探索PRAMEY在表观遗传调控中的作用，我们使用免疫荧光染色技术分析了合子和胚胎中的DNA（5-甲基胞嘧啶（5-mC））和组蛋白（H3K9me3和H3K27me3）甲基化。来自经PRAMEY ab处理精子的合子在10 hpf时父本原核和25 hpf时母本原核中的DNA甲基化显著降低（P≤0.01）。组蛋白甲基化分析显示各组之间H3K9me3甲基化无显著差异，但在8细胞和桑椹胚阶段，使用经PRAMEY ab处理精子产生的胚胎中H3K27me3甲基化显著较低（P≤0.05）。总之，PRAMEY抑制增强了牛胚胎中的精卵结合并影响DNA和组蛋白甲基化动态，突出了其在受精和早期胚胎表观遗传调控中的潜在作用。
