Linking motorneuron fate and connectivity in Drosophila

连接果蝇运动神经元的命运和连接

基本信息

批准号：
7779973
负责人：
Heather Broihier
金额：
$ 30.08万
依托单位：
CASE WESTERN RESERVE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-04-01 至 2012-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7779973
关键词：
Affect Alleles Axon Behavior Biological Biological Assay Biological Models Cells Characteristics Cleaved cell Clinical Cues Data Defect Development Disease Drosophila genus Embryo Event Exhibits Extracellular Matrix Family Genes Genetic Genetic Epistasis Genetic Models Goals Growth Cones Human Development In Vitro Insulin Signaling Pathway Invertebrates Link Matrix Metalloproteinases Medical Metalloproteases Mitotic Modeling Molecular Molecular Genetics Motor Motor Neurons Nervous system structure Neuronal Differentiation Neurons Pathway interactions Pattern Peptide Hydrolases Phenotype Play Population Postdoctoral Fellow Proteins Research Research Personnel Role Screening procedure Series Signal Pathway Signal Transduction Stereotyping Synapses System Transcriptional Regulation Translating axon guidance base extracellular gain of function genetic analysis in vivo interest mutant neural circuit neuromuscular neuron development novel overexpression programs research study response synaptogenesis transcription factor

项目摘要

Our long term aim is to use a genetic approach in Drosophila to understand molecular mechanisms of motorneuron fate specification and differentiation. In this proposal, we focus on mechanisms linking motorneuron fate to axon guidance. In a large-scale screen for mutants affecting motorneuron development, we have identified foxO and Mmp2, both of which are expressed in motorneuron subsets and necessary for proper motor axon guidance. We focus on these two evolutionarily-conserved proteins as they provide us with novel entry points for elucidating how distinct behaviors of motorneurons are developmentally regulated. Our goals here are to complete molecular, genetic, and phenotypic analyses of these genes in order to understand the observed mutant phenotypes. FoxO is a transcription factor best known for its role in the insulin signaling pathway where it is regulated by extracellular signals. Our preliminary data suggest that FoxO is expressed specifically in clusters of motorneurons in response to a target-derived signal. Detailed expression and phenotypic analyses will elucidate the role of FoxO in motorneuron development. Furthermore, we will identify the signaling pathway(s) regulating FoxO expression in motorneurons through molecular and genetic epistasis experiments. Matrix metalloproteinases (Mmps) comprise a large family of. transmembrane and secreted proteases that together cleave nearly every component of the ECM.Mmp2 is expressed in stereotyped populations of motorneurons and is necessary for proper motor axon guidance. We will characterize the expression pattern of Mmp2 in post-mitotic neurons and elucidate its role in motor axon guidance by analyzing motor axon outgrowth in Mmp2 mutant embryos. Additionally, we will establish whether Mmp2 is necessary for motor axon defasciculation by analyzing genetic interactions between Mmp2 and guidance molecules known to regulate this key pathfinding step. These studies will advance our understanding of how molecules acting in distinct motorneuron populations coordinate to establish proper patterns of neuromuscular connectivity. Motorneuron differentiation is an essential event in neuronal development and can be disrupted in human development and disease. Furthermore, since both foxO and Mmp2 are evolutionarily-conserved proteins acting in pathways of intense clinical interest, these studies should have broad biological and medical significance.

我们的长期目的是在果蝇中使用遗传方法来了解分子机制 Motorneuron命运规范和分化。在此提案中，我们专注于链接的机制 Motorneuron命运到轴突指导。在大规模的屏幕中，用于影响运动神经元发育的突变体，我们已经确定了FOXO和MMP2，这两者均以Motorneuron子集表示，对于适当的运动轴突指导。我们专注于这两种进化保存的蛋白质，因为它们为我们提供了有了新的入口点来阐明运动神经元的不同行为在发育中如何受到调节。我们的目标是完成这些基因的分子，遗传和表型分析，以便为了了解观察到的突变表型。 Foxo是转录因素，以其在其中的作用而闻名胰岛素信号通路在其中受细胞外信号调节。我们的初步数据表明 FOXO专为响应于目标衍生的信号而在Motorneurons的簇中表达。详细的表达和表型分析将阐明FOXO在Motorneuron发育中的作用。此外，我们将确定通过通过分子和遗传性上症实验。基质金属蛋白酶（MMP）包括一个大家庭。跨膜和分泌的蛋白酶，它们几乎将ECMP2的每个成分分裂在一起在刻板的运动神经元中表达，对于适当的运动轴突指导是必不可少的。我们将表征MMP2在有丝分裂后神经元中的表达模式，并阐明其在运动中的作用通过分析MMP2突变体胚胎中的运动轴突出现来引导轴突引导。此外，我们将建立 MMP2是否是通过分析MMP2之间的遗传相互作用的运动轴突降压以及已知的指导分子来调节这一关键探路步骤。这些研究将推动我们的了解分子如何在不同的运动神经元种群中作用以建立适当的神经肌肉连通性的模式。 Motorneuron差异化是神经元中的重要事件发展，可能在人类发展和疾病中受到破坏。此外，由于Foxo和 MMP2是作用于强烈临床兴趣途径的进化保存的蛋白，这些研究应该具有广泛的生物学和医学意义。