IN VIVO GLYCOSYLATION PATTERN OF SUBMANDIBULAR GLAND MUCIN

大鼠颌下腺粘蛋白的体内糖基化模式 粘蛋白在口腔中有几个重要的功能，如柔软和 硬组织的涂布和润滑以及口腔的调节 微生物区系。大鼠颌下腺黏蛋白(rSMG黏蛋白)为114 kDa 由蛋白质核心和碳水化合物组成的相对分子质量糖蛋白 O-糖基连接到丝氨酸和苏氨酸的侧链 残留物。蛋白质的糖基化模式既不是随机的，也不是 不受控制，它反映了糖蛋白的功能特性。 蛋白质骨架的构象、序列和序列上下文可以 在指导糖基化方面发挥作用。这项研究的目的是 阐明rSMG粘蛋白在体内的糖基化模式 这种模式与潜在的糖基化位点之间的关系。RSMG粘蛋白 通过阴离子交换和凝胶过滤从腺匀浆中提纯 层析法。糖基化保护蛋白质骨架不受酶的影响 降解，使粘蛋白受到酶的裂解。 从消化过程中得到的纯化糖肽将经过 氨基酸序列分析应提供有关 潜在O-糖基化位点的占有率。更好地理解 引导糖基化的信号将允许它们的操纵，进而 改变粘蛋白的特性。

In vivo glycosylation pattern of rat submandibular gland mucin Mucins have several important functions in the oral cavity such as soft and hard tissue coating and lubrication as well as the modulation of the oral microflora. Rat submandibular gland mucin (RSMG mucin) is a 114 kDa molecular weight glycoprotein made up of a protein core and carbohydrate side chains that are O-glycosidically linked to serine and threonine residues. A protein's glycosylation pattern is neither random nor uncontrolled, and it reflects the functional properties of the glycoprotein. The conformation, sequence, and sequence context of the protein backbone may play roles in directing glycosylation. The purpose of this study is to elucidate the in vivo glycosylation pattern of RSMG mucin and the relationship of this pattern to potential glycosylation sites. RSMG mucin has been purified from gland homogenate by anion exchange and gel filtration chromatography. Glycosylation protects the protein backbone from enzymatic degradation so the mucin was subjected to enzymatic cleavage by pronase. The purified glycopeptides obtained from the digest will be subjected to amino acid sequence analysis which should provide information regarding the occupancy of potential O-glycosylation sites. A better understanding of the signals directing glycosylation will allow their manipulation, and in turn altering mucin properties.