Disruption of O-GlcNAc homeostasis during mammalian oocyte meiotic maturation impacts fertilization.
Disruption of O-GlcNAc homeostasis during mammalian oocyte meiotic maturation impacts fertilization.
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哺乳动物卵母细胞减数分裂成熟过程中 O-GlcNAc 稳态的破坏会影响受精。
DOI：
10.1002/mrd.23131
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发表时间：
2019
影响因子：
2.5
通讯作者：
Duncan,FrancescaE
中科院分区：
文献类型：
--
作者：
Zhou,LuhanT;Romar,Raquel;Pavone,MaryEllen;Soriano-Úbeda,Cristina;Zhang,John;Slawson,Chad;Duncan,FrancescaE
减数分裂成熟和受精是一个需要代谢的过程，因此哺乳动物卵母细胞对营养可利用性的变化非常敏感。O - glcn酰化-在蛋白质上添加单糖残基（O - linked β - N -乙酰氨基葡萄糖）-是一种翻译后修饰，可作为细胞营养传感器并可能调节卵母细胞蛋白质的功能。O‐glcn酰化是由O‐GlcNAc转移酶（OGT）和O‐GlcNAcase （OGA）介导的，前者将O‐GlcNAc添加到蛋白质上，后者将其去除。在这里，我们研究了牛和人卵母细胞在减数分裂期间的do - glcn酰化动力学，并确定了其扰动的发育后遗症。OGA、OGT和多重o‐glcn酰化蛋白在牛卵丘细胞复合体（COCs）中表达，它们定位于整个配子，但也在特定的亚细胞位点富集。O‐glcn酰化蛋白集中在I前期的核膜上，OGA集中在减数分裂期间的皮层上，OGT集中在减数分裂纺锤体上。这些表达模式在人类卵母细胞中是进化保守的。为了检测o‐GlcNAc的功能，我们使用Thiamet‐G (TMG)，一种高选择性的OGA抑制剂，在牛COCs减数分裂成熟过程中破坏了do‐GlcNAc循环。尽管TMG在积云细胞和卵母细胞中导致了inO - glcn酰化底物的显著增加，但对积云的扩大和减数分裂进程没有影响。然而，在TMG中成熟的COCs体外受精后，由于精子穿透、精子头去致密化和原核形成的影响，受精卵的发育明显受到损害。因此，减数分裂成熟过程中o‐GlcNAc的稳态对受精和原核阶段的发育非常重要。
Meiotic maturation and fertilization are metabolically demanding processes, and thus the mammalian oocyte is highly susceptible to changes in nutrient availability.O‐GlcNAcylation—the addition of a single sugar residue (O‐linked β‐N‐acetylglucosamine) on proteins—is a posttranslational modification that acts as a cellular nutrient sensor and likely modulates the function of oocyte proteins.O‐GlcNAcylation is mediated byO‐GlcNAc transferase (OGT), which addsO‐GlcNAc onto proteins, andO‐GlcNAcase (OGA), which removes it. Here we investigatedO‐GlcNAcylation dynamics in bovine and human oocytes during meiosis and determined the developmental sequelae of its perturbation. OGA, OGT, and multipleO‐GlcNAcylated proteins were expressed in bovine cumulus oocyte complexes (COCs), and they were localized throughout the gamete but were also enriched at specific subcellular sites.O‐GlcNAcylated proteins were concentrated at the nuclear envelope at prophase I, OGA at the cortex throughout meiosis, and OGT at the meiotic spindles. These expression patterns were evolutionarily conserved in human oocytes. To examineO‐GlcNAc function, we disruptedO‐GlcNAc cycling during meiotic maturation in bovine COCs using Thiamet‐G (TMG), a highly selective OGA inhibitor. Although TMG resulted in a dramatic increase inO‐GlcNAcylated substrates in both cumulus cells and the oocyte, there was no effect on cumulus expansion or meiotic progression. However, zygote development was significantly compromised following in vitro fertilization of COCs matured in TMG due to the effects on sperm penetration, sperm head decondensation, and pronuclear formation. Thus, properO‐GlcNAc homeostasis during meiotic maturation is important for fertilization and pronuclear stage development.