Zoldoš Vlatka, Grgurević Srđana, Lauc Gordan
Biomol Concepts. 2010 Oct 1;1(3-4):253-61. doi: 10.1515/bmc.2010.027.
Protein N-glycosylation is an ancient metabolic pathway that still exists in all three domains of life (Archaea, Bacteria and Eukarya). The covalent addition of one or more complex oligosaccharides (glycans) to protein backbones greatly diversifies their structures and makes the glycoproteome several orders of magnitude more complex than the proteome itself. Contrary to polypeptides, which are defined by a sequence of nucleotides in the corresponding genes, the glycan part of glycoproteins are encoded in a complex dynamic network of hundreds of proteins, whereby activity is defined by both genetic sequence and the regulation of gene expression. Owing to the complex nature of their biosynthesis, glycans are particularly versatile and apparently a large part of human variation derives from differences in protein glycosylation. Composition of the individual glycome appears to be rather stable, and thus differences in the pattern of glycan synthesis between individuals could originate either from genetic polymorphisms or from stable epigenetic regulation of gene expression in different individuals. Studies of epigenetic modification of genes involved in protein glycosylation are still scarce, but their results indicate that this process might be very important for the regulation of protein glycosylation.
蛋白质N-糖基化是一种古老的代谢途径，至今仍存在于生命的所有三个域（古细菌、细菌和真核生物）中。在蛋白质主链上共价添加一个或多个复杂的寡糖（聚糖）极大地增加了它们结构的多样性，并使糖蛋白质组比蛋白质组本身复杂几个数量级。与由相应基因中的核苷酸序列定义的多肽不同，糖蛋白的聚糖部分是由数百种蛋白质组成的复杂动态网络编码的，其活性由遗传序列和基因表达调控共同决定。由于其生物合成的复杂性，聚糖具有特别的多样性，显然人类变异的很大一部分源于蛋白质糖基化的差异。个体糖组的组成似乎相当稳定，因此个体之间聚糖合成模式的差异可能源于基因多态性或不同个体中基因表达的稳定表观遗传调控。对参与蛋白质糖基化的基因进行表观遗传修饰的研究仍然很少，但研究结果表明，这一过程可能对蛋白质糖基化的调控非常重要。
