LOCUS CONTROL REGION HSI,II AND HGH EXPRESSION

位点控制区 HSI、II 和 HGH 表达

• 批准号: 2905159
• 负责人: BRIAN M SHEWCHUK
• 金额: $ 3.67万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-09-01 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/2905159
• 关键词: binding proteins; gel mobility shift assay; gene expression; genetic mapping; genetic promoter element; genetic regulation; genetic regulatory element; genetically modified animals; laboratory mouse; molecular cloning; somatotropin

The pituitary- and placenta-specific genes of the human growth hormone (hGH) gene cluster are vital to normal growth and physiology during development and in the adult. Misregulation of the hGh gene leads to significant pathological consequences that illustrate its importance in postnatal development. Furthermore, the organization of genes in the cluster and its association with a dominant distal regulatory element, the locus control region (LCR), make it a valuable model for the study of genes in higher eukaryotes that are organized into discrete genomic regulatory domains. The work proposed here will address important questions about the modulation of gene expression during in utero development with a focus on the mechanisms by which LCRs are involved as major determinants in this process. The aims of the proposed research are to study the organization and identity of a subset of regulatory determinants in the hGH LCR ( HSI, II) and their role in the establishment ant maintenance of an hGH transgene in a transcriptionally active state during pituitary development. The region of the LCR involved in the transcriptional activation of the hGH gene in the pituitary has been identified by its DnaseI hypersensitivity (HSI,II) and is the focus of this proposal. In aim I, using a transgenic mouse system, the precise locations of LCR activity will be mapped in the HSI, II region. In Aim II, the discrete elements involved in HSI,II region. In Aim II, the discrete elements involved in HSI,II activity and their corresponding protein factors will be identified and characterized using in vitro protein binding and foot printing assays. There is a strong potential for the discovery of novel regulatory proteins in this Aim, as there are no recognition sequences for known factors in the HSI,II region. Finally, Aim III will determine whether HSI,II is required the maintenance as well as the initial activation of hGH gene expression during pituitary somatotrope cell lineage progression in a transgenic mouse system using a developmentally-regulated conditional deletion of HSI,II. The outcome of this research, if successful , will result in novel insight into the developmental control of human growth hormone gene cluster, the mechanism by which LCRs function, and how gene expression profiles are established and maintained in specific cell lineages during development.

人类生长发育中的脑垂体和胎盘特异性基因 激素(HGH)基因簇对正常生长和生理至关重要 在发育过程中和在成人中。促生长激素基因的错误调控 导致显著的病理后果，说明它的 在出生后发育中的重要性。此外，该组织 及其与显性远端基因的关联 调节元件，基因座控制区(LCR)，使其成为 为研究高等真核生物中的基因提供了有价值的模型 被组织成离散的基因组调节域。这项工作 这里提出的建议将解决有关调制的重要问题 在子宫内发育过程中的基因表达，重点是 LCR作为主要决定因素参与其中的机制 进程。拟议研究的目的是研究 管理决定因素的子集的组织和标识 HGH LCR(HSI，II)及其在建立ANT中的作用 保持hGH转基因处于转录活性状态 在脑下垂体发育过程中。LCR所涉及的区域 HGH基因在垂体中的转录激活已被证实 由其DnaseI超敏反应(HSI，II)确定，是焦点 这项提议。在Aim I中，使用转基因小鼠系统， LCR活动的准确位置将在HSI II中绘制 区域。在AIM II中，涉及HSI，II区的离散元件。 在AIM II中，参与HSI、II活动的离散元素和 它们相应的蛋白质因子将被确定并 利用体外蛋白质结合和足印进行表征 化验。发现小说有很大的潜力 调节蛋白质在这一目标上，因为没有识别 HSI，II区已知因子的序列。最后，AIM III 将确定HSI，II是否需要维护以及 垂体期hGH基因表达的初步激活 转基因小鼠系统中促生长激素细胞的谱系进展 使用发育调节的有条件删除HSI，II。 这项研究的结果，如果成功，将产生新的 洞察人类生长激素基因的发育调控 簇、LCRs的作用机制和基因 在特定细胞中建立和维护表达谱 发育过程中的血统。