SALIVARY MUCIN, SYNTHESIS, PROCESSING AND SECRETION

唾液粘蛋白​​、合成、加工和分泌

• 批准号: 2896934
• 负责人: PAUL C DENNY
• 金额: $ 24.73万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-08-01 至 2001-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2896934
• 关键词: RNase protection assay; aging; antibody; clone cells; complementary DNA; genetic library; genetic polymorphism; genome; glycoprotein biosynthesis; glycosylation; in situ hybridization; laboratory mouse; laboratory rabbit; messenger RNA; mucins; nucleic acid probes; nucleic acid sequence; oligosaccharides; posttranscriptional RNA processing; saliva; salivary glands; secretion; sublingual gland; submandibular gland

Mucins from saliva are a class of glycoproteins whose bioactivities range from formation of protective coatings to aggregation and/or inactivation of specific strains of viruses and oral bacteria. The ultimate goal of this project is to provide a rationale for developing treatments to reverse losses of mucin from salivary glands and saliva such as observed to accompany aging in humans and mice. An understanding of the fundamental processes surrounding mucin synthesis and glycosylation is the key to revealing the origins of the aging-related losses and to development of appropriate treatment responses. The model systems that will be employed for this study of mucin production use the young adult mouse submandibular and sublingual glands. Both glands are included because each makes a unique mucin. These mucins appear to be analogous to the human salivary mucins, MG1 and MG2. In addition, the secretion of each mucin is regulated differently, providing the opportunity for evaluating the secretion and restitution of mucin that is elicited either primarily as a cholinergic or as a beta-adrenergic response. With these systems, transcription, compartmentalization and stability of mucin mRNAs will be measured. Apomucin synthesis and glycosylation will also be evaluated before and after secretion to provide a baseline for comparison of mucin recovery rates in young and aged mice. In preliminary studies, it has been shown that mucin production in both glands can be upregulated by a regimen of chronic hyperstimulation. This upregulation of mucin can also be accomplished in senescent mice leading to levels higher than in young mice. However, it is not known if this approach to reversing the aging effect is appropriate or the underlying cause of the aging-related loss. Thus, the later aspects of this project will focus on gaining a better understanding of which of the mucin production processes decline with aging and which processes are upregulated in response to hyperstimulation. To accomplish the above goals, molecular and immunological probes have been developed. These include cDNA clones for both mucins as well as antisera against both apomucins and their fully glycosylated counterparts. These will be used to quantitate the mucins and their mRNAs. A system for quantitating and sequencing both N- and O-linked oligosaccharides will also be employed. The submandibular and sublingual mucin cDNA clones and a cDNA clone for a salivary cell-specific protein, P2O, that shows sequence homology with mucins will also be used to probe the mouse genome for evidence of their relatedness and or possible gene polymorphism.

唾液中的粘蛋白是一类糖蛋白，其生物活性范围 从保护涂层的形成到聚集和/或失活 特定病毒株和口腔细菌。最终目标是 该项目旨在为开发治疗方法提供理论依据 逆转唾液腺和唾液中粘蛋白的损失，如观察到的 伴随人类和小鼠的衰老。对基本原理的理解 围绕粘蛋白合成和糖基化的过程是关键 揭示与衰老相关的损失的根源和发展 适当的治疗反应。 将用于粘蛋白生产研究的模型系统 使用年轻成年小鼠下颌下腺和舌下腺。两个腺体 包括在内，因为每种都产生独特的粘蛋白。这些粘蛋白似乎是 类似于人类唾液粘蛋白​​ MG1 和 MG2。此外， 每种粘蛋白的分泌受到不同的调节，提供 评估粘蛋白分泌和恢复的机会 主要作为胆碱能或β-肾上腺素能引起 回复。通过这些系统，转录、区室化和 将测量粘蛋白 mRNA 的稳定性。阿朴粘蛋白的合成和 糖基化也将在分泌之前和之后进行评估，以提供 比较年轻和老年小鼠粘蛋白回收率的基线。 初步研究表明，粘蛋白的产生 慢性过度刺激疗法可以上调腺体。这 粘蛋白的上调也可以在衰老小鼠中实现 的水平高于年轻小鼠。不过，尚不清楚这是否 逆转衰老效应的方法是否合适或根本原因 与衰老相关的损失的原因。因此，这个项目的后期方面 将重点更好地了解哪种粘蛋白 生产工艺随着老化而衰退，哪些工艺是 因过度刺激而上调。 为了实现上述目标，分子和免疫学探针已 已开发。其中包括粘蛋白和粘蛋白的 cDNA 克隆 针对阿普粘蛋白及其完全糖基化对应物的抗血清。 这些将用于定量粘蛋白及其 mRNA。一个系统 对 N- 和 O- 连接寡糖进行定量和测序将 也能就业。 颌下和舌下粘蛋白 cDNA 克隆 唾液细胞特异性蛋白 P2O 的 cDNA 克隆，显示 与粘蛋白的序列同源性也将用于探测小鼠基因组 以获得它们相关性和/或可能的基因多态性的证据。