Identification of Core Pathways that Regulate Dendrite Morphology

摘要为了使正常的神经元功能发生，神经元必须有正确数量的输入中心或树突，树突看起来像树上的树枝。然而，目前对这些分支的模式是如何确定的知之甚少。费尔斯坦博士的工作目标是确定调控树突数量的核心途径。费尔斯坦博士将利用分子生物学、生物化学和神经细胞培养来研究这些途径。首先，费尔斯坦博士将建立四个标准来描述树突数量的调节。该系统与用于表征神经递质的标准不同，将有助于确定文献中报道的蛋白质是否确实是树突分支核心通路的成员。实验将集中在两种蛋白质上，即cypin和PSD-95，费尔斯坦博士认为它们是核心通路的组成部分。由于当树突分支时，细胞骨架或树突的支撑结构必须改变，因此实验将评估cypin和PSD-95是否通过改变细胞骨架来改变树突数量。其次，提出的研究将扩展到评估其他假定的蛋白质在树突分支的核心程序中的作用。其他蛋白质将被测试，看看它们是否与cypin和PSD-95一起作用，通过培养海马神经元来改变这些蛋白质的水平。最后，费尔斯坦博士的团队将使用静态图片和视频显微镜拍摄培养海马神经元随时间的图像，并确定树突是如何形成的：通过生长、发芽或缩回。这些研究很重要，因为它们将提供在发育过程中如何调节树突分支以产生功能性大脑的信息。这项研究的影响是深远的。这些实验的表现将成为培养本科生和研究生在神经科学的前沿技术以及实验设计和数据解释的实际方面的计划的一部分。此外，费尔斯坦博士继续指导高中休假的教师。通过让高中教师和学生接触实验生物学，这项拟议中的研究将激励未来的科学家在他们职业生涯的早期阶段。

Firestein - Identification of Core Pathways that Regulate Dendrite MorphologyProposal 0548543Abstract In order for proper neuronal function to occur, the neuron must have the correct number of input centers, or dendrites, which look like branches on a tree. However, very little is currently known about how the pattern of these branches is determined. The goal of Dr. Firestein's work is to identify core pathways by which dendrite number is regulated. Dr. Firestein will make use of molecular biology, biochemistry, and neuronal cell culture to investigate these pathways. First, Dr. Firestein will establish four criteria by which to characterize regulators of dendrite number. This system, not unlike criteria used to characterize neurotransmitters, will help to identify whether proteins reported in the literature are indeed members of core pathways for dendrite branching. Experiments will focus on two proteins, cypin and PSD-95, which Dr. Firestein believes to be components of the core pathway. Since the cytoskeleton, or supporting structure of a dendrite, must change when a dendrite branches, experiments will assess whether cypin and PSD-95 change dendrite number by altering the cytoskeleton. Second, the proposed studies will be extended to assess the role of other presumed proteins in the core program of dendrite branching. Other proteins will be tested to see if they they act together with cypin and PSD-95 by using cultured hippocampal neurons that have altered levels of these proteins. Finally, Dr. Firestein's group will take images of cultured hippocampal neurons over time using both static pictures and video microscopy and identify how dendrites form: via outgrowth, sprouting, or retraction. These studies are important because they will provide information on how dendrite branching is regulated during development to yield a functional brain. The impact of this research is far-reaching. The performance of the experiments will be part of a program to train undergraduate and graduate students in cutting-edge techniques in neuroscience and in practical aspects of experimental design and data interpretation. Furthermore, Dr. Firestein continues to mentor teachers on sabbatical from high school. By exposing high school teachers and students to experimental biology, the proposed research will motivate future scientists at a very early stage in their careers.