Genetic Regulation of Complex Neurological Disease

描述（申请人提供）：此竞争修订版应用程序的目标是（NOT-OD-09-058 - NIH宣布为竞争性修订申请提供恢复法案资金）是对我们当前计划的补充（NS 061971）研究Brunol 4突变小鼠中复杂癫痫发作障碍的分子基础，通过使用条件基因表达和电生理学检查癫痫发作表型的细胞基础。我们已经发表了Brunol 4杂合突变体具有边缘系统和强直阵挛性癫痫发作以及低癫痫发作阈值，纯合突变体也具有自发性失神癫痫发作。使用时间条件删除，我们最近确定，它是足够的删除Brunol 4在7周龄，以降低癫痫发作阈值，并产生自发性边缘系统和强直阵挛性惊厥。这是非常宝贵的信息，因为它表明，未来对生物学机制的研究可以集中在Brunol的成年维持功能上，而不是发育本身。此外，通过使用空间条件性缺失，我们还确定了从皮层和海马兴奋性神经元中去除Brunol 4可能是惊厥发作表型的一部分，但不是全部，这为复杂性提供了进一步的生物学见解。在竞争性修订的第一部分中，我们将通过检查从抑制性神经元中删除Brunol 4的影响来完成条件研究。我们还将通过结合两种不同的cre驱动程序（即兴奋性和抑制性）来评估复合条件删除的影响。在第二部分中，我们将进行膜片钳电生理记录的神经元在生殖细胞和条件突变，给进一步了解在细胞水平上的突变对突触活动的影响。这将与我们的同事张博士合作，他是脑切片电生理学专家。目前资助的项目的扩展，其目标完全是分子性质的，将完成我们在这种动物模型中复杂癫痫发作障碍的“生物学”的初步研究。此外，我们很高兴有可能利用这一机会为我们的研究能力增加新的工具。这些对于完善Brunol 4计划以及为将来对我们的其他疾病模型的机制洞察提供机会都至关重要。 公共卫生相关性：最常见的医疗条件，如心脏病，癌症，自身免疫和脑部疾病，往往是遗传复杂的，受多个基因与其他因素，如饮食和环境的相互作用。这种复杂性使得研究和了解常见疾病的原因成为一项挑战。在这个项目中，我们将研究一个名为Brunol 4的基因的功能，它通过引起许多其他基因的错误表达来模拟大脑的遗传复杂性“兴奋性”障碍。了解Brunol 4在分子和细胞水平上的功能将有助于我们了解基因在大脑中是如何以及为什么被协调调节的，并可能为未来的治疗提供新的切入点。

DESCRIPTION (provided by applicant): The goal of this Competitive Revision application (NOT-OD-09-058 - NIH Announces the Availability of Recovery Act Funds for Competitive Revision Applications) is to complement our current program (NS061971) to study the molecular basis of complex seizure disorder in Brunol4 mutant mice, by examining the cellular basis of the seizure phenotypes using conditional gene expression and electrophysiology. We already published that Brunol4 heterozygous mutants have limbic and tonic-clonic seizures and a low seizure threshold, and homozygous mutants also have spontaneous absence seizures. Using temporal conditional deletion, we recently determined that it is sufficient to delete Brunol4 at 7 wks of age to lower seizure threshold and to produce spontaneous limbic and tonic-clonic convulsions. This was invaluable information to have as it suggests that future investigation into the biological mechanism can focus on adult, maintenance functions of Brunol4 rather than development per se. In addition, by using spatial conditional deletion, we also determined that removing of Brunol4 from cortical and hippocampal excitatory neurons may account for a portion, but not all, of the convulsive seizure phenotype-providing further biological insight into the complexity. In the first part of the competitive revision, we will complete the conditional studies by examining the effects of deleting Brunol4 from inhibitory neurons. We will also assess the effects of compound conditional deletion by combining two different cre drivers (i.e. excitatory and inhibitory). In the second part, we will perform patch-clamp electrophysiological recordings of neurons in germline and conditional mutants, to give further insight into effect of the mutation on synaptic activity at the cellular level. This will be in collaboration with our colleague Dr. Zhang, an expert in brain slice electrophysiology. This extension of the currently funded program, in which the aims are entirely molecular in nature, will complete our initial picture of the 'biology' of the complex seizure disorder in this animal model. In addition, we are excited about the possibility of using this as an opportunity to add new tools to our research abilities. These will be critical both for rounding-out the Brunol4 program, and for providing opportunities for mechanistic insight into our other disease models in the future. PUBLIC HEALTH RELEVANCE: The most common medical conditions, such as heart disease, cancer, autoimmune and brain disorders, are often genetically complex, influenced by the interaction of multiple genes with other factors such as diet and environment. This complexity makes it a challenge to study and to understand the causes of common disease. In this program we will study the function of a gene, called Brunol4, which mimics a genetically complex "excitability" disorder of the brain by causing the misexpression of many other genes. Learning how Brunol4 functions at the molecular and cellular level will help us to understand how and why genes are coordinately regulated in the brain and may provide new entry points for future therapies.