CELL-SPECIFIC HORMONAL REGULATION OF GENE EXPRESSION

基因表达的细胞特异性激素调节

• 批准号: 2414897
• 负责人: MICHEL M SANDERS
• 金额: $ 17.25万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-05-01 至 1999-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2414897
• 关键词: DNA binding protein; DNA footprinting; chemical binding; chickens; developmental genetics; estrogens; fallopian tubes; gel mobility shift assay; gene expression; gene induction /repression; genetic regulatory element; genetic transcription; hormone regulation /control mechanism; molecular cloning; nucleic acid sequence; ovalbumin; transcription factor; transfection

Differential gene expression is the underlying determinant for cellular diversity and differentiated cell function in complex organisms. Thus, elucidation of the basis for cell-specific gene expression is required for a molecular understanding of development and differentiation. The activation and/or repression of specific genes is triggered by external messages that act through signal transduction pathways that are largely ubiquitous. An additional level of complexity exists for genes that are regulated by hormones and growth factors; those genes can exhibit cell- specificity for induced expression as well as for basal expression. The long term goal of our research is to understand how hormonal, developmental, and tissue-specific cues integrate to precisely control the activities of complex genes. The focus of the research in this proposal is to study cell-specific hormonal induction by identifying the cell-specific elements in the chicken ovalbumin gene. This expression of this gene is restricted to the tubular gland cells of the avian oviduct and is regulated by four classes of steroid hormones and by the peptide hormone insulin. The specific hypothesis being tested is that the cell-specific expression of the ovalbumin gene is achieved via positive activation by hormones in oviduct and direct repression by unknown factors in nonoviduct tissues. The Specific Aims are to I). identify and characterize the positive cell-specific regulatory elements in the ovalbumin gene, II). clone the proteins that bind to the positive cell-specific elements, and III). identify the elements in the ovalbumin gene that repress its expression in inappropriate tissues. The identification and characterization of the relevant DNA elements will be accomplished by combination of in vivo footprinting, gel mobility shift assays, and gene transfections. The cloning of the associated proteins will be attempted by a one-hybrid yeast genetic selection system or by other techniques that rely on the DNA binding properties of the proteins. Elucidation of the underlying mechanisms involved in the generation and maintenance of differentiated cells may provide the basis for understanding how events go awry in some diseases such as cancer that involve extensive alterations in cellular phenotype and proliferation. Furthermore, the avian oviduct has the potential for producing large amounts of easily purified proteins if expression can be targeted to that organ. This has implications for research and for therapeutic and commercial purposes.

差异基因表达是细胞凋亡的潜在决定因素。 复杂生物体中的多样性和分化的细胞功能。因此，在本发明中， 需要阐明细胞特异性基因表达的基础， 对发育和分化的分子理解。的 特定基因的激活和/或抑制是由外部因素触发的。 这些信息通过信号转导途径起作用， 无处不在基因的复杂性还有一个额外的层次， 受激素和生长因子的调节;这些基因可以表现出细胞- 诱导表达以及基础表达的特异性。的 我们研究的长期目标是了解荷尔蒙， 发育和组织特异性的线索整合，以精确地控制 复杂基因的活动。本提案的研究重点是 研究细胞特异性激素诱导， 鸡卵清蛋白基因中的元件。这种基因的表达 仅限于鸟类输卵管的管状腺细胞， 由四类类固醇激素和肽激素调节 胰岛素正在测试的具体假设是，细胞特异性 卵清蛋白基因的表达是通过以下方式的正激活实现的： 输卵管内的激素和非输卵管内未知因素的直接阻遏 组织中具体目标是（）。识别和描述 卵清蛋白基因中的阳性细胞特异性调节元件，II）。 克隆与阳性细胞特异性元件结合的蛋白质，和 III）。确定卵清蛋白基因中抑制其表达的元件， 在不适当的组织中表达。确定和 相关DNA元件的表征将通过以下方式完成： 体内足迹法、凝胶迁移率变动测定法和基因转移测定法的组合 转染相关蛋白质的克隆将尝试通过 单杂交酵母遗传选择系统或通过其它技术， 依赖于蛋白质的DNA结合特性。 阐明参与产生和 维持分化的细胞可能为 了解一些疾病如癌症中的事件是如何出错的， 涉及细胞表型和增殖的广泛改变。 此外，鸟类输卵管具有产生大量 大量容易纯化的蛋白质，如果表达可以靶向于 器官.这对研究、治疗和 商业用途。