T-CADHERIN FUNCTIONS IN NEURAL DEVELOPMENT

T-钙粘蛋白在神经发育中的功能

• 批准号: 6108532
• 负责人: BARBARA RANSCHT
• 金额: $ 21.28万
• 依托单位: SANFORD BURNHAM PREBYS MEDICAL DISCOVERY INSTITUTE
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-12-01 至 2000-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6108532
• 关键词: G protein; antibody neutralization test; antisense nucleic acid; biological signal transduction; brain mapping; cadherins; cell cell interaction; chick embryo; dendrites; developmental neurobiology; embryo /fetus tissue /cell culture; enzyme substrate; gene expression; glycoproteins; growth cones; laboratory mouse; laboratory rabbit; membrane proteins; monoclonal antibody; neural cell adhesion molecules; neural plate /tube; neurogenesis; phosphorylation; protein structure function; transfection

The establishment of specific axon connections depends on the interaction of growth cone receptors with positive and negative guidance cues in the neuronal environment. T-cadherin (Ranscht and Dours-Zimmermann, Neuron 7:391-402) is distributed on subpopulations of growing axons and delineates specific regions in the pathway of growing commissural and motor axons. Preliminary functional studies suggest that T-cadherin acts as an inhibitor of neurite growth. The current proposal aims to extend knowledge about the distribution of T-cadherin to the CNS and to experimentally define the function and mechanism of T-cadherin in axon growth and pathway selection using in vitro assays. First, we will study T-cadherin's spatial and temporal distribution in the developing chick brain and specifically focus on the expression pattern during early neurogenesis. Second, we will determine the effect of T-cadherin substrates on neurite growth and growth cone recognition in vitro. Different neuron populations will be tested for their responses to T-cadherin using both uniform T-cadherin substrates and choice assays. In both assays, growth cone interactions with T-cadherin will be compared to those with neurite-promoting N-cadherin. Possible effects will be neutralized with specific antibodies, recombinant proteins and antisense oligonucleotides. Third, to study the mechanism of T- cadherin-induced growth cone responses, we will determine if T-cadherin- elicited growth cone responses involve homophilic or heterophilic recognition. We will determine if T-cadherin-induced growth cone interaction induce signal transduction events in the growth cone and obtain evidence for or against the participation of G-proteins, calcium-signaling and phosphorylation events. Fourth, we will define the responsible molecular domains that regulate T-cadherin-induced growth cone avoidance and N-cadherin-simulated neurite growth. We will test mutated T-cadherin molecule, in which selected regions of T-cadherin are eliminated or replaced with the corresponding region of N-cadherin and vice versa, in neurite growth and choice assays.

特定轴突连接的建立取决于相互作用 具有正面和负引导线索的生长锥受体 神经元环境。 T-钙粘蛋白（Ranscht和Dours-Zimmermann，Neuron 7：391-402）分布在生长轴突的亚群上 特定区域的特定区域在变化和运动轴突的途径中。 初步功能研究表明，T-钙粘蛋白充当抑制剂 神经突的生长。 当前的建议旨在扩展有关 T-钙粘着蛋白在中枢神经系统中的分布并实验定义 T-钙粘着蛋白在轴突生长和途径选择中的功能和机制 使用体外测定。 首先，我们将研究T-钙粘蛋白的空间和 发育中的小鸡大脑的时间分布，特别是集中 关于早期神经发生过程中的表达模式。 第二，我们会的 确定T-钙粘蛋白底物对神经突生长和生长的影响 锥体识别体外。 将测试不同的神经元种群 它们使用均匀T-钙粘蛋白底物和 选择测定。 在这两个测定中，生长锥与T-钙粘蛋白的相互作用 将与那些促进神经突的N-钙粘着蛋白的人进行比较。 可能的 效果将用特定抗体，重组蛋白中和 和反义寡核苷酸。 第三，研究t-的机制 钙粘着蛋白诱导的生长锥反应，我们将确定是否t-钙粘蛋白 - 引起的生长锥反应涉及均电或异质 认出。 我们将确定T-钙粘蛋白诱导的生长锥是否 相互作用诱导生长锥中的信号转导事件并获得 G蛋白，钙信号的证据或反对参与 和磷酸化事件。 第四，我们将定义负责任的 调节T-钙粘蛋白诱导的生长锥的分子结构域 和N-钙粘蛋白模拟的神经突生长。 我们将测试突变的T-钙粘蛋白 分子，其中取消了T-钙粘蛋白的选定区域或 用N-钙粘蛋白的相应区域取代，反之亦然， 神经突的生长和选择分析。