MINERALIZATION STUDIES RELATED TO ORAL BIOLOGY

拟议的研究将集中在基质囊泡的酶上，这些酶在 牙齿的矿化。基质小泡是亚显微的，细胞外的， 作为矿化初始位置的膜包裹颗粒 牙本质，以及包括软骨和骨在内的其他口腔组织。我们的实验室是 参与基质囊泡的原始鉴定和它们的 随后的分离和部分表征。我们已经提供了证据 基质囊泡磷酸酶(包括ATPase、焦磷酸酶和碱性磷酸酶 磷酸酶)参与触发矿化。此外，这些 磷酸酶驻留在囊泡膜表面，可被 保留酶活性和活性的脱氧胆酸盐处理 钙沉积能力。两种一般类型的增溶研究 酶的提出：1)化学提纯和性质 分子大小、抑制剂、底物和辅因子要求和2)分析 含电子囊泡磷酸酶对钙蓄积的调控 对这一过程的微观研究。 这是对正常牙本质和其他 矿化的形式也随之产生。组织分离技术， 放射性同位素标记和计数、酶生物化学和电子 将使用显微技术。基质囊泡钙化的新知识可以 适用于广泛的主题，包括特定的疾病状态 有异常钙化。

The proposed study will focus on enzymes of matrix vesicles which play a role in the mineralization of teeth. Matrix vesicles are submicroscopic, extracellular, membrane-invested particles which serve as the initial loci of mineralization of dentin, and of other oral tissues including cartilage and bone. Our lab was involved in the original identification of matrix vesicles and in their subsequent isolation and partial characterization. We have provided evidence that matrix vesicle phosphatases (including ATPase, pyrophosphatase and alkaline phosphatase) are involved in triggering mineralization. Furthermore, these phosphatases reside on the vesicle membrane surface and can be solubilized by deoxycholate treatment with preservation of enzymatic activity and calcium-depositing ability. Two general types of studies with the solubilized enzyme are proposed: 1) chemical purification and characterization as to molecular size, inhibitors, substrate and cofactor requirements and 2) analysis and control of calcium accumulation by vesicle phosphatase including an electron microscopic study of this process. This is a fundamental study of the mechanism by which normal dentinal and other forms of mineralization are brought about. Techniques for tissue fractionation, radioisotopic labelling and counting, enzyme biochemistry and electron microscopy will be employed. New knowledge of matrix vesicle calcification can be applied to a broad range of topics including specific disease states in which there is abnormal calcification.