REGULATION OF KERATINIZATION BY HORMONES AND VITAMINS

我们的研究是针对上皮分化的正常和 病理状态 这项补助金的重点是维生素和 激素，例如类维生素A和甲状腺激素，在对照组中 角蛋白的合成和角化过程中。 几十年来， 临床医生已经认识到，甲状腺激素和维生素A有深刻的影响， 对正常和异常皮肤的影响， 维生素A及其衍生物在角化疾病中的应用 已经广泛传播。 与此同时，对其他系统的研究 在细胞和分子水平上定义了这些 影响基因表达的物质;它们与特定的 受体，其又与非编码区中的识别元件反应， 对转录产生深远影响的DNA区域。 实验将 我们将重点放在表皮角蛋白的几个基因上， 显示受视黄酸及其受体的负调节， 以及甲状腺激素及其受体。 使用的测定将基于 当转染涉及角蛋白基因的调节区时， 报告基因，或者氯霉素乙酰转移酶，用于定量 研究或荧光素酶用于定位研究。 承认要素 两种受体复合物的角蛋白基因将通过 删除研究。 特定的点突变将定义其确切的 岗位 在这些研究中，聚合酶链反应（PCR） 将用于扩增DNA的适当区域。 平行研究将 在上皮细胞的细胞系和原代培养物中进行。 最后，研究了类维生素A和甲状腺激素对分化的影响。 将测定组织培养中的表皮。 因此，我们的目标是在5 我们请求支持的年份将是： 1.识别和表征识别元素（RE）， 人角蛋白维甲酸和甲状腺激素核受体 基因-基底细胞特异性K#5和K#14，皮层特异性K#10， 过度增殖相关的K#6和K#16，以及单纯上皮细胞- K#8、K#17、K#18和K#19。 2.来确定维甲酸和甲状腺激素 激素调节角蛋白基因的表达，并描绘相互作用 在两类介质及其受体之间; 3.分析类维生素A和甲状腺激素对表皮生长因子的影响， 体外分化。 我们的建议，这将定义类维生素A的作用机制， 甲状腺激素，对健康有重要意义 因为它最终将导致对正常和病理的理解 过程中的皮肤，并应表明新的治疗潜力 剂.

Our research is directed at epithelial differentiation in normal and pathologic states. This grant focuses on the roles of vitamins and hormones, as exemplified by retinoids and thyroid hormones, in the control of keratin synthesis and in the process of keratinization. For decades, clinicians have recognized that thyroid hormones and vitamin A had profound effects upon normal and abnormal skin and within recent years the interest in the use of vitamin A and its derivatives on diseases of keratinization has become widespread. At the same time studies of other systems have defined on cellular and molecular levels the mechanism by which these substances effect regulation of gene expression; they bind to specific receptors which in turn react with recognition elements in the non-coding regions of DNA to profoundly affect transcription. The experiments will focus upon several genes for epidermal keratins whose expression we have shown to be negatively regulated by both retinoic acid and its receptor as well as thyroid hormone and its receptor. The assays used will be based upon transfection involving regulatory regions of keratin genes linked to a reporter gene, either chloramphenicol acetyl transferase for quantitative studies or luciferase for localization studies. The recognition elements in the keratin gene for both receptor complexes will be identified through deletion studies. Specific point mutations will define their exact positions. Throughout these studies, the polymerase chain reaction (PCR) will be used to amplify appropriate areas of DNA. Parallel studies will be undertaken in cell lines and primary cultures of epithelial cells. Finally, the effects of retinoids and thyroid hormones on differentiating epidermis in tissue culture will be determined. Thus, our aims in the 5 years for which we are requesting support will be: 1. to identify and characterize the recognition elements (REs) for the nuclear receptors of retinoic acid and thyroid hormone in human keratin genes - basal cell-specific K#5 and K#14, stratum corneum-specific K#10, hyperproliferation-associated K#6 and K#16, and the simple-epithelia- specific K#8, K#17, K#18 and K#19. 2. to define the molecular mechanisms by which retinoids and thyroid hormones regulate keratin gene expression and to delineate the interactions among the two classes of mediators and their receptors; 3. to analyze the effects of retinoids and thyroid hormones on epidermal differentiation in vitro. Our proposal, which will define the mechanisms of action of retinoids and thyroid hormones in epidermis, has important implications for health care for it will ultimately lead to understanding of the normal and pathologic processes in skin and should indicate the potential of new therapeutic agents.