ENAMEL SECRETORY MATRIX PROTEASE

牙釉质分泌基质蛋白酶

• 批准号: 3220444
• 负责人: MILES A CRENSHAW
• 金额: $ 7.51万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 1984
• 资助国家: 美国
• 起止时间: 1984-07-01 至 1987-10-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3220444
• 关键词: affinity chromatography; chemical cleavage; dental development; embryo /fetus; enamel organ; enzyme structure; enzyme substrate; extracellular matrix; molecular weight; peptidases; protease inhibitor; proteolysis; radiotracer; secretion; serine; tissue /cell culture

Most of the matrix protein that is deposited in enamel during the secretory stage is lost during the postsecretory development of enamel. This protein loss is preceded by marked decreases in the molecular weights of the matrix proteins. It has been postulated that this molecular weight decrease is accomplished by a proteolytic enzyme that is secreted with the matrix. A serine protease activity in developing enamel has been reported. In preliminary studies, we have isolated a proteolytic enzyme from embryonic bovine secretory enamel. This enzyme represents a small fraction of the total matrix protein, and it has very low activity until it is separated from the bulk of the protein by affinity chromatography. The enzyme calcium-activated. This project is designed to further characterize this enzyme and to study its effect on developing enamel matrix. The specific aims are as follows: (1) to purify the serine protease and to determine the specificity of bonds cleaved by this enzyme using model substrates and enamel matrix; (2) to determine whether the enzyme hydrolyzes amelogenins, enamelins, or both; (3) to determine whether the enzyme is secreted as a protenzyme or with an inhibitor; and (4) to determine whether inhibitors of the enzyme inhibit the in vitro loss from enamel of previously synthesized matrix proteins.

分泌期沉积在釉质中的大部分基质蛋白 阶段在釉质的分泌后发育期间丢失。 这种蛋白质 损失之前是基质分子量的显著降低 proteins. 据推测，这种分子量降低是由于 通过与基质一起分泌的蛋白水解酶完成。 一 已经报道了发育中的釉质中的丝氨酸蛋白酶活性。 在初步的研究中，我们已经分离出一种蛋白水解酶， 胎牛分泌釉质 这种酶代表了 的总基质蛋白，它有非常低的活性，直到它是 通过亲和层析从蛋白质本体中分离。 的 钙激活酶 该项目旨在进一步表征 这种酶并研究其对牙釉质基质发育的影响。 具体目的如下：（1）纯化丝氨酸蛋白酶， 使用模型确定由该酶切割的键的特异性 底物和釉质基质;（2）确定酶是否 水解釉原蛋白、釉蛋白或两者;（3）确定所述牙釉质蛋白是否 酶作为蛋白酶或与抑制剂一起分泌;和（4） 确定该酶的抑制剂是否抑制来自该酶的体外损失。 先前合成的基质蛋白质的釉质。