Development of the calyx of Held

描述(由申请人提供)：涉及突触后靶点的输入之间的竞争，获胜输入的增长和稳定，以及神经在突触伙伴协调成熟中的作用的因素没有很好地描述。这种情况在一定程度上源于这些事件在大多数神经系统中的长期性。我们发现，大的神经末梢支配听觉脑干中的细胞是研究这些事件的一个很好的模型系统。小的终端相互竞争，然后一个获胜的输入在出生后2-4天之间的48小时内生长到包裹目标的细胞体。我们将利用这一受限制的时间框架，利用微阵列技术来研究基因表达的开始和偏移。我们建议使用外显子微阵列分析来自P2-4周围基因表达的密集时间采样的每日间隔数据。从P2-4的个体表达谱与突触发生事件时间相关的基因中，我们将选择25个候选基因通过定量实时聚合酶链式反应、免疫组织化学和原位杂交进行验证。更复杂的分析，如基因簇或基于选择性剪接的方法，将产生额外的基因列表，将从其中选择另外25个候选基因进行验证。这些活动将需要招聘来填补两个新职位。通过与约翰·霍普金斯大学的蒋谦博士的一项新合作，将聘请一名博士后研究员协助钱博士进行微阵列分析。在西弗吉尼亚大学，将聘请一名研究技术员来促进对选定候选基因的高通量验证。这些新创造的就业机会，以及更有效地进行定量聚合酶链式反应实验所需的设备，将加快科学研究的步伐。本申请是根据拨款通知编号：NOT-09-058提交的，通知标题：NIH宣布恢复法案资金可用于竞争力修订申请。 与公共卫生相关：大脑中的信息处理障碍是一系列神经病理的特征，这些病理可以追溯到早期发育过程中神经回路的不正确形成。拟议的研究旨在发现神经回路形成背后的一般原理。因此，这项工作的见解可能会支持听力障碍的治疗策略，如听觉处理障碍和阅读障碍。

DESCRIPTION (provided by applicant): The factors involved in competition among inputs for a postsynaptic target, growth and stabilization of winning inputs, and the role of innervation in coordinated maturation of synaptic partners are not well delineated. In part this situation stems from the protracted nature of these events in most neural systems. We have revealed that innervation of cells in the auditory brainstem by large nerve terminals called calyces of Held is a good model system to study these events. Small terminals compete, then a single winning input grows to envelop the cell body of its target within 48 hours, between postnatal (P) days 2-4. We will take advantage of this constrained time frame to study onset and offset of gene expression using microarray technology. We propose here to analyze data from dense temporal sampling of gene expression surrounding P2-4 in daily intervals using exon microarrays. From genes whose individual expression profile is temporally linked to synaptogenesis events at P2-4, we will select 25 candidates for validation by using quantitative real-time PCR, immunohistochemistry and in situ hybridization. More complex analyses, such as gene cluster or alternative splicing-based methods, will yield an additional list of genes from which another 25 candidates will be selected for validation. These activities will require recruitment to fill two new positions. Through a new collaboration with Jiang Qian, PhD, at Johns Hopkins University, a postdoctoral fellow will be hired to assist Dr. Qian with microarray analyses. At West Virginia University, a research technician will be hired to facilitate high throughput validation of selected candidate genes. These newly created jobs, along with requested equipment to more efficiently perform qPCR experiments, will accelerate the tempo of scientific research. This application is submitted in accordance with grant Notice Number: NOT-09-058 and Notice Title: NIH Announces the Availability of Recovery Act Funds for Competittivce Revision Applications. PUBLIC HEALTH RELEVANCE: Disorders of information processing in the brain characterize a range of neurologic pathologies that can be traced to improper formation of neural circuits during early development. The proposed studies are designed to discover general principles that underlie neural circuit formation. Therefore, insights from this work may underpin therapeutic strategies for deficits in hearing, such as auditory processing disorder and dyslexia.