CNS DEVELOPMENT AND GENE ACTION

这些研究的总体目标是确定基因如何指导 哺乳动物中枢神经系统的发展。 研究基因突变 神经系统的发育提供了一个理想的Vantage位置来接近这一点 问题.韦弗突变小鼠是本提案的主题， 将对韦弗基因（wv）的两个方面进行研究： l）将使用以下技术来寻找编织者基因的身份： 染色体显微切割、克隆和cDNA筛选。这种方法 利用最新的发展和 韦弗突变的染色体碱基此外， 韦弗基因座将继续使用亚种杂交和DNA标记， 鉴定更接近织布工的限制性片段长度多态性 基因座，并创建用于鉴定wv基因的重要工具。 2)一个细胞发育部分将表征wv的目标 正常和突变大脑中的小脑细胞。实验将 我还提出了一个假设，即韦弗突变破坏了这一过程， 导致细胞死亡我们将采用 轴突标记物在颗粒细胞轴突动力学成像中的体内应用 正常和突变小脑的生长。超微结构研究将有助于 表征遗传正常和织纹颗粒细胞， 韦弗表型的病因学中的细胞病理学诊断 颗粒细胞死亡。 这些研究旨在全面了解 单基因座，wv：它对各种细胞类型的影响， 哺乳动物基因组及其与大脑的关系 发展 特别是新生儿小脑的大量丧失 颗粒细胞和黑质多巴胺能神经元的进行性丢失 神经元发生在韦弗是病理类似的损失， 这些神经元在人类小脑发育不全的情况下， 帕金森氏症。

The overall objective of these studies is to determine how genes instruct the development of the mammalian CNS. The study of mutations that affect nervous system development offers an ideal vantage point to approach this problem. The weaver mutant mouse is the subject of the present proposal, and two aspects of the weaver gene (wv) will be examined: l) The identity of the weaver gene will be sought using the techniques of chromosomal microdissection, cloning, and cDNA screening. This approach takes advantage of the most recent advances in the developmental and chromosomal bases of the weaver mutation. Additionally, the mapping of the weaver locus will be continued using subspecies crosses and DNA markers to identify restriction fragment length polymorphisms closer to the weaver locus and to create tools important for the identification of the wv gene. 2) A cellular developmental section will characterize a target of the wv gene, the cerebellar cell in normal and mutant brains. Experiments will also address the hypothesis that the weaver mutation disrupts the process of axonal outgrowth which then leads to cell death. We will employ the invivo use of axonal markers to image the dynamics of granule cell axonal growth in normal and mutant cerebella. Ultrastructural studies will help characterize genetically normal and weaver granule cells for a broader diagnosis of cell pathology in the etiology of the weaver phenotype of granule cell death. These studies are aimed at obtaining a comprehensive understanding of a single locus, wv: its impact on various cell types, its localization in the mammalian genome, and its contextual relationship to brain development. In particular, the massive neonatal loss of cerebellar granule cells and the progressive loss of substantia nigra dopaminergic neurons that occurs in weaver is pathologically similar to the loss of these neurons in the human conditions of cerebellar hypoplasia and Parkinson's disease.