CHARACTERIZATION AND FUNCTION OF STEROID REGULATED GENES IN MANDUCA

曼杜卡类固醇调控基因的特征和功能

• 批准号: 6112368
• 负责人: DAVID B MORTON
• 金额: --
• 依托单位: UNIVERSITY OF ARIZONA
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-01 至 1999-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6112368
• 关键词: DNA binding protein; Manduca; developmental genetics; developmental neurobiology; genetic regulation; genetic transcription; hormone regulation /control mechanism; invertebrate hormone; molting; neurogenetics; nuclear runoff assay; protein biosynthesis; steroid hormone; steroid hormone receptor; tissue /cell culture; transcription factor

Many cellular functions are regulated by change in genome expression. One major class of compounds which mediate these changes are hormones acting via members of the steroid/thyroid receptor superfamily. These hormone receptors alter gene expression by binding to specific regions of DNA and regulating transcription of adjacent genes. The nature of these regions of DNA and the functions of the genes regulated are of central importance to the understanding of normal physiological function, development and disease. Non-mammalian model systems have been invaluable in understanding the basic mechanisms of gene regulation by these hormones in all organisms. Studies by a number of investigators have shown the importance of using insects such as Drosophila melanogaster and Manduca sexta for such model systems. Both a rise in steroid levels and a decline can act as the signal which alters cellular function by an increase in the transcription of specific genes. The differences between the two mechanisms involved are, as yet, unclear. This project will use the insect, Manduca sexta, as a model system to characterize genes in the nervous system, whose transcription is increased by the declining levels of the steroid hormones, the ecdysteroids. Insect ecdysteroid receptors and their specific DNA binding sites have a high degree of homology with vertebrate steroid receptors, thus the mechanisms of regulation are likely to be conserved. We have isolated several genes from the nervous system of Manduca sexta whose transcripts increase in abundance as steroid levels decline. The specific steroid requirements for expression of one of these genes will be investigated with a combination of in vivo and in vitro manipulations of ecdysteroid levels. The transcription rate of this gene will be determined during development to test whether the regulation is at the transcriptional level. The effect of protein synthesis inhibitors on the levels of transcript will be determined and factors involved in the decline in transcript levels will be investigated. Studies on the regulatory regions of the gene and presence of potential regulatory proteins will be initiated. One long-term of this project is to determine the function of these genes in the development of the nervous system. An analysis of the developmental and spatial expression patterns of additional genes of this type will be completed to correlate the known physiological changes taking place in the nervous system with the presence of a particular transcript.

许多细胞功能受基因组表达变化的调节。 一 介导这些变化的主要化合物是激素作用 通过类固醇/甲状腺受体超家族的成员。 这些激素 受体通过与DNA的特定区域结合而改变基因表达 调节相邻基因的转录。 这些地区的本质 DNA和受调节基因的功能对 对正常生理功能，发展和 疾病。 非哺乳动物模型系统在理解方面非常宝贵 这些激素在所有生物体中调节基因调节的基本机制。 许多研究人员的研究表明了使用的重要性 果蝇果蝇等昆虫为此模型 系统。 类固醇水平的升高和下降都可以作为信号 通过增加特定的转录来改变细胞功能 基因。 涉及两种机制之间的差异至今仍是 不清楚。 该项目将使用昆虫甘达·塞克斯塔（Manduca Sexta）作为模型 在神经系统中表征基因的系统，神经系统的转录为 通过类固醇激素的水平下降增加， ecdysteroids。 昆虫ecdysteroid受体及其特异性DNA结合 位点具有高度与脊椎动物类固醇受体的同源性， 因此，调节机制可能是可以保存的。 我们已经从Manduca Sexta神经系统中分离了几个基因 随着类固醇水平下降，其转录本的丰度增加。 这 这些基因之一表达表达的特定类固醇要求将是 通过体内和体外操作的结合 ecdysteroid水平。 该基因的转录率将确定 在开发过程中测试调节是否处于转录 等级。 蛋白质合成抑制剂对水平的影响 笔录将确定，并涉及下降的因素 笔录水平将被研究。 监管区域的研究 基因和潜在调节蛋白的存在将是 发起。 该项目的长期是确定这些基因的功能 在神经系统的发展中。 对发展的分析 这种类型的其他基因的空间表达模式将是 完成以关联已知的生理变化 神经系统具有特定转录本的存在。