ROLE OF GLUTAMYLTRANSPEPTIDASE IN TOOTH DEVELOPMENT

伽玛-谷氨酰转肽酶，GGT，在具有 活跃在分泌和吸收过程中。它已经被发现是 与具有刷子边框的单元格紧密关联。的细胞 成釉细胞的釉质器官，尤其是成釉细胞，在 它们的生命周期。它们从相对未分化的细胞开始，变成 活跃的分泌细胞，后来在成熟阶段它们变成 活跃的吸收细胞。由于釉质蛋白中含有较高比例的 (约20%)的氨基酸、谷氨酸，发育中的牙齿可以 作为研究发育调节酶的极佳模型 GGT活性。到目前为止，只有一份报告表明GGT 存在于发育中的牙齿(Lindskog和Hammarstrom，1981)。确实是 表示只有在基质生产阶段才有活动 (不是在此之前)，在成熟过程中表现出更强的活性 舞台。免疫组织化学在本实验室的初步研究 染色和灵敏的荧光分析表明，在 釉质基质GGT的合成存在于成釉细胞的釉器中 刚出生的老鼠的磨牙。这项建议旨在研究本地化。 以及不同发育阶段釉质器官中GGT的活性。 希望通过这样的研究，能够更多地了解 这种酶的功能，更具体地说，它在形成过程中的作用 和釉质的成熟。由于GGT是一种膜结合酶，它还可以 是研究膜动力学的一种方便的标志酶 牙釉质分泌和成熟期的流动 成釉细胞正在进行调节。

The enzyme Gamma -glutamyl transpeptidase, GGT, is found in cells which are active in secretory and resorptive processes. It has been found to be strongly associated with cells which possess a brush border. The cells of the enamel organ, especially the ameloblasts, undergo profound changes in their life cycle. They begin as relatively undifferentiated cells, become active secretory cells and later during the stage of maturation they become active resorptive cells. Since enamel proteins contain a high proportion (about 20%) of the amino acid, glutamic acid, the developing tooth could serve as an excellent model for studying developmentally regulated enzyme activity of GGT. Thus far there is only one report showing that GGT is present in developing teeth (Lindskog and Hammarstrom, 1981). It was stated that activity was only present during the stage of matrix production (not before) and that stronger activity was present in the maturation stage. Preliminary studies in this laboratory using immunohistochemical staining and a sensitive fluorometric assay have shown that prior to the synthesis of enamel matrix GGT is present and active in the enamel organ of newborn mouse molars. This proposal is designed to study the localization and activity of GGT in the enamel organ at various stages of development. It is hoped that through a study such as this more will be learned of the function of this enzyme and more specifically of its role in the formation and maturation of enamel. Since GGT is a membrane bound enzyme it may also prove to be a convenient marker enzyme to study the dynamics of membrane flow during enamel secretion and during the maturation stage when ameloblasts are modulating.