GnRH Multiplicity: Molecular and Developmental Studies

GnRH 多样性：分子和发育研究

• 批准号: 0548620
• 负责人: Yonathan Zohar
• 金额: $ 29万
• 依托单位: University of Maryland Biotechnology Institute
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-02-01 至 2010-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0548620&HistoricalAwards=false
• 关键词: GnRH; Multiplicity; Molecular; Developmental; Studies

The gonadotropin-releasing hormone (GnRH) neuropeptides function as keyhormones in the control of reproduction in all vertebrates, and it is now firmly established thateach species expresses more than one form of GnRH. Several lines of evidence indicate thateach form has distinct, and possibly multiple, functions within an organism, although anunderstanding of what these functions are and how they are coordinated is far from complete.An emerging area of investigation in the study of GnRH functionality concerns theirpresence during embryonic and juvenile development. These studies will examine the expression patterns and functional aspects of GnRH during development in the zebrafish, a modelorganism in which two forms of GnRH have been characterized. Building on preliminary data that demonstrates different patterns of expression for each form of GnRH during embryonic and early larval development in zebrafish, these studies will achieve two general objectives. First, using techniques to localize and quantitate gene expression, the ontogeny and detailed expression patterns of GnRH-I and GnRH-II within the zebrafish brain during embryonic and larval life stages will be determined, and correlated with several parameters of brain, pituitary and gonadal development. Second, functional roles of each form of GnRH in terms of establishment of the reproductive axis will be examined by determining the effects of disrupted GnRH-I and GnRH-II expression on development of the brain, pituitary and gonad in embryonic and larval zebrafish. This objective will be achieved by 1) temporarily knocking down GnRH expression during development by injecting antisense oligonucleotides into zebrafish embryos and 2) creating transgenic zebrafish that constantly under-express the GnRH peptides in a tissue-specific manner. To date, there has been no in-depth analysis of the expression of GnRHsduring embryonic or juvenile development in vertebrates. These studies will alleviateshortcomings in the current state of knowledge in the field of GnRH research, and provide abetter understanding of the functional significance of GnRH multiplicity. These studies will alsoestablish the necessary tools and baseline data for further studies of GnRH functionality in a model system that is universally recognized as ideal for studying development and regulation of gene expression patterns, which is currently lacking in the field. The use of transgenic technologies will enable the modeling of physiological states in which there is an induced or genetically inherited disruption of proper GnRH expression. Thus, aside from the basic knowledge to be gained, these studies will have broader impacts for the understanding of reproductive development in vertebrates generally, and will potentially impact the manipulation of reproduction in farmed and captive animals. These studies will provide state-of-the-art training for postdoctoral, graduate and undergraduate researchers. In addition, because of the chosen model system, the experimental tools derived from these studies will be easily adapted to develop teaching modules that will give hands-on experience in neurobiology, embryonic development and molecular analysis of gene expression to high school and undergraduate students and secondary school teachers.

促性腺激素释放激素(GnRH)神经肽在所有脊椎动物的生殖控制中起着关键激素的作用，现在已经确定每个物种都表达不止一种形式的GnRH。有几条证据表明，每种形式在生物体内都有不同的，甚至可能是多种功能，尽管对这些功能是什么以及它们是如何协调的理解还远未完成。GnRH功能研究中一个新兴的研究领域涉及它们在胚胎和幼年发育期间的存在。这些研究将研究GnRH在斑马鱼发育过程中的表达模式和功能方面，斑马鱼是一种模式生物，已经表征了两种形式的GnRH。基于初步数据，这些数据显示了在斑马鱼胚胎和早期幼体发育过程中，每种形式的促性腺激素释放激素的不同表达模式，这些研究将实现两个总体目标。首先，利用基因表达的定位和定量技术，将确定GnRH-I和GnRH-II在斑马鱼胚胎和幼体生活期的个体发育和详细表达模式，并与脑、脑垂体和性腺发育的一些参数相关联。其次，将通过确定GnRH-I和GnRH-II表达中断对斑马鱼胚胎和幼体的脑、脑垂体和性腺发育的影响来研究每种形式的GnRH在建立生殖轴方面的功能作用。这一目标将通过1)通过向斑马鱼胚胎中注射反义寡核苷酸来暂时抑制GnRH在发育过程中的表达和2)创造以组织特异性方式持续低表达GnRH多肽的转基因斑马鱼来实现。到目前为止，还没有深入分析GnRHS在脊椎动物胚胎或幼体发育过程中的表达。这些研究将缓解GnRH研究领域知识现状的不足，并更好地理解GnRH多样性的功能意义。这些研究还将为在模型系统中进一步研究GnRH功能建立必要的工具和基线数据，该模型系统被普遍认为是研究基因表达模式的发展和调控的理想工具，而目前该领域缺乏这一模型系统。转基因技术的使用将使对生理状态的建模成为可能，在这种状态下，正常的GnRH表达会受到诱导或遗传破坏。因此，除了要获得的基本知识外，这些研究还将对了解脊椎动物的生殖发育产生更广泛的影响，并可能影响对饲养和圈养动物生殖的操纵。这些研究将为博士后、研究生和本科生研究人员提供最先进的培训。此外，由于所选择的模型系统，从这些研究中得出的实验工具将很容易地用于开发教学模块，这些模块将为高中和本科生以及中学教师提供神经生物学、胚胎发育和基因表达的分子分析方面的实践经验。