MULTIHORMONAL REGULATION OF GENE EXPRESSION

大多数真核基因都受到多因素调控，通过 发育、激素、组织特异性和/或环境线索。这个 因此，由基因产生的蛋白质净量必须反映出这些 信号整合。我们的长期目标是了解这些复杂的 调控事件协调一致，以诱导适当水平的基因 表情。鸡卵清蛋白(Ov)基因是一个很好的模型 研究基因表达的多因素调控，因为它是 四类类固醇在转录水平上的调节 激素，由胰岛素和其他正负调节因子在体内 严格针对特定组织的方式。这项建议的主要重点是 了解类固醇激素如何激活卵子基因。的固有特性 对这个问题的理解是对类固醇如何发挥作用的分析 协同激活迟反应基因。因为大多数基因都能诱导 通过类固醇是这一类的成员，这是至关重要的 对激活之间的中间事件的理解 类固醇受体对早期基因的影响以及随后的激活 迟来的基因。这笔赠款的具体目的是：一、确定和 表征调节类固醇反应的早期反应蛋白 Ov基因，II.研究类固醇激素的协同作用 关于Ov基因的转录，以及III.研究Ov基因的作用 调控卵子基因表达的负性调控元件。至 为此，我们将克隆和鉴定基因调控蛋白。 与卵子基因中的主要调控元件相结合， 类固醇依赖调节元件(SDRE)及其负性调节 元素(NRE)。连接子扫描突变的转染法实验 通过SDRE和NRE来定义特定的角色 每个蛋白质结合部位。基因组足迹将被用来帮助 在确定两种类固醇如何实现协同作用以及SDRE如何 和NRE作为一个单一的功能实体。类固醇荷尔蒙已经 与某些癌症的病因有关，更好地理解 类固醇引发的分子事件只会改善治疗和 这些恶性肿瘤的预防。此外，这种知识可以 为开发更好的避孕药具提供见解并帮助 生殖障碍的治疗。

Most eucaryotic genes are subject to multifactorial regulation by developmental, hormonal, tissue-specific, and/or environmental cues. The net amount of protein made from a gene must therefore reflect how these signals integrate. Our long term goal is to understand how these complex regulatory events are coordinated to elicit appropriate levels of gene expression. The chicken ovalbumin (Ov) gene serves as an excellent model for studying multifactorial regulation of gene expression because it is regulated at the transcriptional level by four classes of steroid hormones, by insulin, and by other positive and negative modulators in a strictly tissue-specific manner. The major focus of this proposal is to understand how steroid hormones activate the Ov gene. Intrinsic to the comprehension of this problem is an analysis of how steroids function synergistically to activate late response genes. As most genes induced by steroids are members of this class, it is essential that an understanding be achieved of the intermediary events between activation of the early genes by steroid receptors and the subsequent activation of the late genes. The Specific Aims of this grant are to I. Identify and characterize the steroid-responsive early response proteins that regulate the Ov gene, II. Investigate the synergistic effects of steroid hormones on the transcription of the Ov gene, and III. Examine the role of the negative regulatory element in modulating expression of the Ov gene. To this end, the gene regulatory proteins will be cloned and characterized that bind to the major regulatory elements in the Ov gene, the steroid-dependent regulatory element (SDRE) and the negative regulatory element (NRE). Transfection experiments with linker scanning mutations through the SDRE and NRE will be employed to define specific roles for each protein binding site. Genomic footprinting will be done to assist in determining how synergism is achieved by two steroids and how the SDRE and NRE act as a single functional entity. As steroid hormones have been implicated in the etiology of some cancers, a better understanding of the molecular events triggered by steroids can only improve the treatment and prevention of these malignancies. Furthermore, such knowledge may provide insights into the development of better contraceptives and aid in the treatment of reproductive disorders.