Université Lille Nord de France, 59000 Lille, France.
J Muscle Res Cell Motil. 2009 Dec;30(7-8):281-7. doi: 10.1007/s10974-010-9201-1. Epub 2010 Feb 25.
There is growing evidence that O-linked N-acetyl-D-glucosaminylation, more simply termed O-GlcNAcylation or O-GlcNAc, is a post-translational modification involved in many cellular processes from transcription to modulation of protein properties. O-GlcNAc is a dynamic and reversible glycosylation and therefore quite similar to the phosphorylation/dephosphorylation process, with which O-GlcNAc can interplay. Since O-GlcNAc serves as a glucose sensor by the way of hexosamine biosynthesis pathway, this glycosylation is often associated with glucose toxicity and development of insulin resistance. In this way, O-GlcNAc could be involved in muscle pathological consequences of diabetes. Nevertheless, in regards of several studies performed in healthy striated muscles, O-GlcNAc seems to exert protective effects against different types of injuries. Recent new insights suggest a key implication of O-GlcNAc in skeletal and cardiac muscles contractile activity, in particular by O-GlcNAc modification of motor as well as regulating contractile proteins. While evidence linked O-GlcNAc to the regulation of calcium activation properties, its exact role remains to be defined as well as the existence of potential interference with phosphorylation. The better understanding of the exact function of OGlcNAc in this physiological process could contribute to the determination of newly markers of skeletal dysfunctions.
越来越多的证据表明，O-连接 N-乙酰-D-氨基葡萄糖基化（更简单地称为 O-GlcNAc 或 O-GlcNAc）是一种翻译后修饰，参与从转录到调节蛋白质性质的许多细胞过程。O-GlcNAc 是一种动态且可逆的糖基化，因此与磷酸化/去磷酸化过程非常相似，O-GlcNAc 可以与磷酸化/去磷酸化过程相互作用。由于 O-GlcNAc 通过己糖胺生物合成途径充当葡萄糖传感器，因此这种糖基化通常与葡萄糖毒性和胰岛素抵抗的发展有关。通过这种方式，O-GlcNAc 可能参与糖尿病引起的肌肉病理后果。然而，关于在健康横纹肌中进行的几项研究，O-GlcNAc 似乎对各种类型的损伤具有保护作用。最近的新见解表明，O-GlcNAc 对骨骼肌和心肌收缩活动具有关键影响，特别是通过 O-GlcNAc 修饰运动蛋白和调节收缩蛋白。虽然有证据表明 O-GlcNAc 与钙激活特性的调节有关，但它的确切作用以及与磷酸化的潜在干扰仍有待确定。更好地了解 OGlcNAc 在这个生理过程中的确切功能，可能有助于确定骨骼肌功能障碍的新标志物。
