Structure and Function of Human Salivary Mucins

产品说明：两种不同的粘蛋白存在于下颌下腺、舌下腺和小唾液腺的分泌物中，一种称为MG 1的大的多聚体凝胶形成粘蛋白和一种称为MG 2的小的单体粘蛋白。MG 1似乎是两种粘蛋白基因产物MUC 5 B和一种新鉴定的粘蛋白MUC 19的混合物。MG 2似乎含有单个粘蛋白基因产物MUC 7。粘蛋白保护口腔表面免受干燥，润滑硬组织和软组织以促进咀嚼、言语和吞咽，并在下面的上皮表面和外部环境之间形成选择性渗透的扩散屏障。我们已经表明，MG 1和MG 2与其他唾液蛋白形成异型复合物，并证实以前归因于粘蛋白的许多功能可以归因于其复合物伴侣的性质。本项目的总体目标是了解唾液分泌物和全唾液中粘蛋白和粘蛋白复合物的分子组成如何影响其在口腔中的生物学功能。该项目的具体目标是： 1)使用基于质谱的蛋白质组学方法鉴定与MG 1形成复合物的唾液蛋白; 2)分离并鉴定与MG 2相互作用的唾液蛋白; 3)探索粘蛋白复合物的功能特性，使用测定来测量复合物伴侣的特定生物学特性; 4)研究在哺乳动物细胞系中表达的凝胶形成粘蛋白的组装机制; 5)使用捕获ELISA测定全唾液和唾液分泌物中凝胶形成粘蛋白的分子组成和分泌模式。

DESCRIPTION: Two distinct mucins occur in the secretions of submandibular, sublingual and minor salivary glands, a large multimeric gel forming mucin named MG1 and a small monomeric mucin named MG2. MG1 appears to be a mixture of two mucin gene products, MUC5B and a newly identified mucin, MUC19. MG2 appears to contain a single mucin gene product, MUC7. Mucins protect oral surfaces against desiccation, lubricate hard and soft tissues to facilitate mastication, speech and swallowing and form a selectively permeable diffusion barrier between underlying epithelial surfaces and the external environment. We have shown that both MG1 and MG2 form heterotypic complexes with other salivary proteins and posit that many of the functions previously attributed to mucins can be ascribed to the nature of their complex partners. The overall goal of this project is to understand how the molecular composition of mucins and mucin complexes in salivary secretions and whole saliva affects their biological function in the oral cavity. The Specific Aims of this project are to: 1) Identify salivary proteins that form complexes with MG1 using a mass spectrometry based proteomics approach; 2) Isolate and identify salivary proteins that interact with MG2; 3) Explore the functional properties of mucin complexes using assays to measure the specific biological properties of complex partners; 4) Investigate the mechanism for assembly of gel-forming mucins expressed in mammalian cell lines; and 5) Determine the molecular composition and secretion patterns of gel forming mucins in whole saliva and salivary secretions using capture ELISAs.