Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, College of Animal Science and Technology & College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, China.
Department of Cardiovascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China.
Mol Hum Reprod. 2024 Feb 1;30(2). doi: 10.1093/molehr/gaae003.
O-linked β-N-acetylglucosamine (O-GlcNAc) modification exists widely in cells, playing a crucial role in the regulation of important biological processes such as transcription, translation, metabolism, and the cell cycle. O-GlcNAc modification is an inducible reversible dynamic protein post-translational modification, which regulates complex cellular activities through transient glycosylation and deglycosylation. O-GlcNAc glycosylation is specifically regulated by O-GlcNAc glycosyltransferase (O-GlcNAc transferase, OGT) and O-GlcNAc glycoside hydrolase (O-GlcNAcase). However, the mechanisms underlying the effects of O-GlcNAc modification on the female reproductive system, especially oocyte quality, remain unclear. Here, we found that after OGT was inhibited, porcine oocytes failed to extrude the first polar body and exhibited abnormal actin and microtubule assembly. Meanwhile, the mitochondrial dynamics and function were also disrupted after inhibition of OGT function, resulting in the occurrence of oxidative stress and autophagy. Collectively, these results inform our understanding of the importance of the glycosylation process for oocyte maturation, especially for the maturation quality of porcine oocytes, and the alteration of O-GlcNAc in oocytes to regulate cellular events deserves further investigation.
O-连接β-N-乙酰氨基葡萄糖（O-GlcNAc）修饰广泛存在于细胞中，在转录、翻译、代谢和细胞周期等重要生物学过程的调节中起着关键作用。O-GlcNAc 修饰是一种诱导性的、可逆的动态蛋白质翻译后修饰，通过短暂的糖基化和去糖基化来调节复杂的细胞活动。O-GlcNAc 糖基化受 O-GlcNAc 糖基转移酶（O-GlcNAc transferase，OGT）和 O-GlcNAc 糖苷水解酶（O-GlcNAcase）的特异性调节。然而，O-GlcNAc 修饰对雌性生殖系统，特别是卵母细胞质量的影响机制尚不清楚。在这里，我们发现 OGT 被抑制后，猪卵母细胞无法排出第一极体，并表现出异常的肌动蛋白和微管组装。同时，OGT 功能被抑制后，线粒体动力学和功能也被破坏，导致氧化应激和自噬的发生。综上所述，这些结果表明我们对糖基化过程对卵母细胞成熟的重要性有了更深入的了解，特别是对猪卵母细胞成熟质量的影响，卵母细胞中 O-GlcNAc 的改变对调节细胞事件值得进一步研究。
