REGULATION OF MUCIN GLYCOPROTEIN BIOSYNTHESIS

上皮表面被一层粘稠的粘弹性涂层所保护 称为粘液。这一层是防御的第一条线 机械、微生物或化学物质对底层组织的侮辱。 具有特殊功能意义的是高度糖基化的， 粘蛋白-糖蛋白。这些分子负责 粘液涂层的独特流变性。许多人 口干症的症状，包括粘膜 溃疡，斑块介导的疾病和 非典型口腔感染与数量上的 唾液粘蛋白缺乏或质变。我们的方法是 这个问题一直以来都是研究正常粘蛋白的调节。 糖蛋白生物合成。通过这种方式，我们希望能够洞察到 唾液的特殊形式可能存在的机制 功能障碍。 我们建议：(1)构建和表征编码哪些片段的cDNA 对于大鼠下颌下腺粘蛋白的蛋白质核心- 糖蛋白(MG)，(2)确定编码 脱脂粘蛋白和谷氨酰胺/谷氨酸富含蛋白(GRP)， 这是在老鼠体内发现的另一类丰富的蛋白质 颌下腺，(3)定义两者的生物合成途径 MG和GRP和，(4)继续澄清结构 以及编码GRP的基因的组织。

Epithelial surfaces are protected by a slimy, visco-elastic coat termed mucus. This layer is the first line of defense against mechanical, microbial or chemical insult to the underlying tissues. Of particular functional significance are the highly glycosylated, mucin-glycoproteins. These molecules are responsible for the unique rheological properties of the mucus coat. Many of the symptoms which characterize xerostomia including mucosal ulceration, increased incidences of plaque mediated disease and atypical oral infections have been linked to either a quantitative lack of or qualitative change in salivary mucin. Our approach to this problem has been to study the regulation of normal mucin- glycoprotein biosynthesis. In this way we hope to gain insight into the mechanisms which may underlie specific forms of salivary dysfunction. We propose to: (1) construct and characterize cDNAs which code for the protein core of rat submandibular gland mucin- glycoprotein (MG), (2) determine levels of mRNA coding for the apo-mucin and the glutamine/glutamic acid rich proteins (GRP), which are another class of abundant proteins found in the rat submandibular gland, (3) define the biosynthetic pathway for both the MG and GRP and, (4) continue clarification of the structure and organization of genes which code for the GRP.