O-linked β-N-acetylglucosamine (O-GlcNAc) is a dynamic form of intracellular glycosylation common in animals, plants and other organisms. O-GlcNAcylation is essential in mammalian cells and is dysregulated in myriad human diseases, such as cancer, neurodegeneration and metabolic syndrome. Despite this pathophysiological significance, key aspects of O-GlcNAc signaling remain incompletely understood, including its impact on fundamental cell biological processes. Here, we investigate the role of O-GlcNAcylation in the coat protein II complex (COPII), a system universally conserved in eukaryotes that mediates anterograde vesicle trafficking from the endoplasmic reticulum. We identify new O-GlcNAcylation sites on Sec24C, Sec24D and Sec31A, core components of the COPII system, and provide evidence for potential nutrient-sensitive pathway regulation through site-specific glycosylation. Our work suggests a new connection between metabolism and trafficking through the conduit of COPII protein O-GlcNAcylation.

中文翻译：

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O-GlcNAc 酰化对 COPII 外壳进行营养依赖性调节的证据

O-连接 β- N-乙酰氨基葡萄糖 (O-GlcNAc) 是动物、植物和其他生物体中常见的细胞内糖基化的动态形式。O-GlcNAc 酰化在哺乳动物细胞中至关重要，并且在多种人类疾病中失调，例如癌症、神经变性和代谢综合征。尽管具有这种病理生理学意义，但 O-GlcNAc 信号传导的关键方面仍未完全了解，包括其对基本细胞生物过程的影响。在这里，我们研究了 O-GlcNAc 酰化在外壳蛋白 II 复合物 (COPII) 中的作用，该复合物是真核生物中普遍保守的系统，介导内质网的顺行囊泡运输。我们在 COPII 系统的核心组成部分 Sec24C、Sec24D 和 Sec31A 上确定了新的 O-GlcNAcNAc 基化位点，并为通过位点特异性糖基化进行潜在的营养敏感途径调节提供了证据。我们的工作表明，通过 COPII 蛋白 O-GlcNAc 酰化的管道，代谢和运输之间存在新的联系。