Brain region-specific epileptogenesis in a conditional mouse model

条件小鼠模型中大脑区域特异性癫痫发生

• 批准号: 394774701
• 负责人: Professor Dr. Holger Lerche
• 金额: --
• 依托单位: Abteilung für Neurologie mit Schwerpunkt Epileptologie
• 依托单位国家: 德国
• 项目类别: Research Units
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/394774701?language=en
• 关键词: Brain; region; specific; epileptogenesis; conditional

Despite the identification of a steadily increasing number of epilepsy genes and elucidation of molecular mechanisms of disease-causing mutations in heterologous expression systems, the exact mechanisms as to how epilepsy develops on the basis of a genetic defect is poorly understood. Functional studies in neurons and animal models offer interesting opportunities to understand the mechanisms underlying epileptogenesis and may pave the way for novel treatment options. Following the main hypothesis of this Research Unit (RU), epilepsy likely develops as a consequence of three interacting processes: the neurophysiological effect of the genetic mutation itself, an epileptogenic process triggered by the mutation, and developmentally regulated physiological changes of network properties within the brain. Therefore, we intend to understand the cascade caused by a molecular genetic dysfunction that triggers cellular changes of neuronal excitability and consecutively affects network function over time ending in epileptic seizures. We will use conditional mouse models in which we can switch on the genetic defect in a region- and time-specific manner to pursue the following aims: (i) to identify relevant brain regions and critical developmental time windows involved in the generation of certain seizure types using conditional region-specific expression of mutant genes; we will start with a conditional Scn1aA1783V mouse model in which we activate the mutation by local injection of viruses transducing Cre-recombinase; (ii) to explore in the same models the contribution and activity patterns of inhibitory and excitatory neurons and circuits in brain regions with an activated mutation using electrophysiology and Ca2+ imaging in vitro and in vivo; (iii) to understand transcriptional changes during epileptogenesis using cell-specific RNA-seq analyses before and after area- and time-specific activation of the mutation as a complementation of the neurophysiological studies of (i) and (ii). In addition, we will (iv) study interesting mutations that have been newly detected in projects P1-3 by studying their neurophysiological consequences using patch clamping and extracellular recordings either in transfected /transduced neuronal cell cultures or in brain slices from KI mouse models.

尽管越来越多的癫痫基因的鉴定和异源表达系统中致病突变的分子机制的阐明，癫痫如何发展的遗传缺陷的基础上的确切机制知之甚少。神经元和动物模型的功能研究提供了有趣的机会，了解癫痫发生的机制，并可能为新的治疗方案铺平道路。根据该研究单位（RU）的主要假设，癫痫的发生可能是三个相互作用过程的结果：基因突变本身的神经生理学效应，突变引发的癫痫过程，以及大脑内网络特性的发育调节生理变化。因此，我们打算了解由分子遗传功能障碍引起的级联反应，该分子遗传功能障碍触发神经元兴奋性的细胞变化，并随着时间的推移连续影响网络功能，最终导致癫痫发作。我们将使用条件性小鼠模型，其中我们可以以区域和时间特异性方式开启遗传缺陷，以实现以下目标：（i）使用突变基因的条件性区域特异性表达来鉴定参与某些癫痫发作类型产生的相关脑区域和关键发育时间窗;我们将从条件Scn 1aA 1783 V小鼠模型开始，其中我们通过局部注射转导Cre重组酶的病毒来激活突变;（ii）在相同的模型中，使用电生理学和Ca 2+探索具有激活突变的脑区域中抑制性和兴奋性神经元和回路的贡献和活动模式体外和体内成像;（iii）在突变的区域和时间特异性激活之前和之后使用细胞特异性RNA-seq分析来理解癫痫发生期间的转录变化，作为（i）和（ii）的神经生理学研究的补充。此外，我们将（iv）通过使用膜片钳和细胞外记录在转染/转导的神经元细胞培养物或KI小鼠模型的脑切片中研究其神经生理学后果，研究在项目P1-3中新检测到的有趣突变。