REGULATION OF KERATINIZATION BY HORMONES AND VITAMINS

我们的研究针对正常和正常皮肤上皮细胞分化。 病理状态。这笔赠款的重点是维生素和 激素，如维甲酸和甲状腺激素，在对照中 角蛋白的合成和角质化过程中。几十年来， 临床医生已经认识到，甲状腺激素和维生素A具有深远的 对正常和异常皮肤的影响以及近年来的兴趣 维生素A及其衍生物在角化性疾病中的应用 已经变得很普遍。与此同时，对其他系统的研究也 在细胞和分子水平上定义了这些 物质影响基因表达的调节；它们与特定的 受体进而与非编码中的识别元件发生反应 DNA的区域会深刻地影响转录。这些实验将会 关注表皮角蛋白的几个基因，我们已经有了它们的表达 视黄酸及其受体AS的负性调节作用 以及甲状腺激素及其受体。使用的化验将基于 在涉及角蛋白基因的调节区的情况下 一个报告基因，氯霉素乙酰转移酶用于定量 研究或用于定位研究的荧光素酶。识别要素 在角蛋白基因中，两种受体的复合体都将通过 删除研究。特定的点突变将定义其确切的 各就各位。在这些研究中，聚合酶链式反应(PCR) 将被用来扩增DNA的适当区域。平行研究将是 在细胞系和上皮细胞的原代培养中进行。 最后，维甲酸和甲状腺激素对分化的影响 将确定组织培养中的表皮。因此，我们在5个方面的目标是 我们请求支持的年份将是： 1.识别和表征识别元素(RE) 人角蛋白中维甲酸和甲状腺激素的核受体 基因-基底细胞特异的K#5和K#14，角质层特异的K#10， 与高增殖相关的K#6和K#16，以及单纯上皮细胞- 具体的K#8、K#17、K#18和K#19。 2.明确维甲酸和甲状腺的分子机制。 激素对角蛋白基因表达的调控及其相互作用 在两类介体及其受体之间； 3.分析维甲酸和甲状腺激素对表皮的影响。 体外分化。 我们的提案将定义维甲酸和维甲酸的作用机制 表皮中的甲状腺激素，对保健有重要意义 因为它最终将导致对正常和病理的理解 在皮肤中的过程，并应表明新的治疗方法的潜力 探员们。

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.