MINERALIZATION STUDIES RELATED TO ORAL BIOLOGY

拟议的研究将集中在基质囊泡（MV），发挥作用， 在牙齿和骨骼的矿化中起起始作用。mv被 亚微观细胞外，膜包颗粒，作为 牙本质、生长板软骨和 发育中的骨骼我们的实验室参与了第一次鉴定， MV的分离和表征。 我们和其他人提供了 有证据表明MV磷酸酶，包括碱性磷酸酶（ALP）， ATP酶参与MV矿化。此外，这些磷酸酶 整合到矿物质首先出现的MV膜中， 这表明MV膜的组分在 开始钙化。我们的具体目标是 增加对分子和结构组织的了解， MV膜和SAP，重点是识别和定位主要 组成蛋白，测试MV的功能，并研究MVs的功能。 通过培养的骨或软骨祖细胞调节MV生物发生 细胞具体目的：1）鉴定可能 在钙化中起作用，包括骨的非胶原蛋白 (bone唾液酸蛋白、骨桥蛋白、骨粘连蛋白、骨钙素）、钙蛋白酶，和 P-糖蛋白2)孤立MV的实验性钙化， 阐明囊泡磷酸酶的作用，特别是ALP和ATP酶， 以及钙化机制中的其他整合MV蛋白。3)一 通过质膜出芽研究MV的生物合成机制， 检查MV生物发生的可能调节剂（例如，骨 形态发生蛋白）以及MV生物发生与 分化和程序性细胞死亡（凋亡）。 这是一个基础性的研究机制， 开始了矿化的骨骼形式。矩阵的新知识 囊泡钙化可以应用于广泛的主题 包括发生异常钙化的特定疾病。

The proposed study will focus on matrix vesicles (MVs) which play an initiating role in mineralization of teeth and bones. MVs are submicroscopic extracellular, membrane-invested particles that serve as the initial site of calcification in dentin, growth plate cartilage and developing bone. Our lab was involved in the first identification, isolation and characterization of MVs. We and others have provided evidence that MV phosphatases, including alkaline phosphatase (ALP), and ATPase are involved in MV mineralization. Furthermore, these phosphatase are integrated into the MV membrane which mineral first appears, suggesting a critical role for components of the MV membrane in initiating calcification. Our specific aims are directed toward an increased understanding of the molecular and structural organization of the MV membrane and sap with emphasis on identify and localizing major constitutive proteins, testing the function of MVs, and studying the regulation of MV biogenesis by cultured bone or cartilage progenitor cells. Specific aims: 1) Identification of major MV proteins that may play a role in calcification, including non-collagenous proteins of bone (bone sialoprotein, osteopontin, osteonectin, osteocalcin), calpain, and P-glycoprotein. 2) Experimental calcification of isolated MVs to further elucidate the role of vesicle phosphatases, especially ALP and ATPase, plus other integral MV proteins in the calcification mechanism. 3) a study of the mechanism of MV biogenesis by plasma membrane budding, examining possible regulators of MV biogenesis (e.g. the bone morphogenetic proteins) and the relation of MV biogenesis to differentiation and programmed cell death (apoptosis). This is a fundamental study of the mechanism by which dental and skeletal forms of mineralization are initiated. New knowledge of matrix vesicle calcification can be applied to a broad range of topics including specific diseases in which abnormal calcification occurs.