CELL-SPECIFIC HORMONAL REGULATION OF GENE EXPRESSION

基因表达的细胞特异性激素调节

• 批准号: 2150575
• 负责人: MICHEL M SANDERS
• 金额: $ 14.12万
• 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/2150575
• 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的潜在决定因素 复杂生物中的多样性和分化的细胞功能。因此， 需要阐明细胞特异性基因表达的基础 对发展和分化的分子理解。这 特定基因的激活和/或抑制是由外部触发的 通过信号转导途径起作用的消息 无处不在。对于基因而言，还有一个额外的复杂性 受荷尔蒙和生长因子的调节；这些基因可以表现出细胞 - 诱导表达和基础表达的特异性。这 我们研究的长期目标是了解荷尔蒙如何 发育和组织特异性提示可以精确控制 复杂基因的活性。研究的重点是 通过鉴定细胞特异性来研究细胞特异性激素诱导 鸡卵形基因基因中的元素。该基因的这种表达是 仅限于禽卵的管状腺细胞，IS 由四类类固醇激素和肽激素调节 胰岛素。测试的特定假设是细胞特异性 椭圆蛋白基因的表达是通过阳性激活来实现的 非卵巢中未知因子的卵形激素和直接抑制 组织。具体目标是我）。识别并表征 卵巢蛋白基因中的阳性细胞特异性调节元素，II）。 克隆与阳性细胞特异性元件结合的蛋白质，并 iii）。识别卵巢蛋白基因抑制其元素 在不适当的组织中表达。标识和 相关DNA元素的表征将通过 体内足迹，凝胶迁移率分析和基因的组合 转染。相关蛋白的克隆将尝试 一种杂交酵母遗传选择系统或其他技术 依靠蛋白质的DNA结合特性。 阐明一代中涉及的基本机制 维护分化细胞可能为 了解事件如何在某些疾病（例如癌症）中出现问题 涉及细胞表型和增殖的广泛改变。 此外，禽卵有可能产生大的 如果可以将表达靶向，则易于纯化的蛋白质 器官。这对研究和治疗和 商业目的。