Control of neuron activity and animal behavior by non-coding RNAs

 描述(由申请人提供)：目前的项目致力于通过microRNAs对神经元活动的一种新的调节机制及其在控制动物行为和癫痫中的作用。我们发现，一种富含神经元的microRNA miR-128在小鼠中扮演着神经元信号反应的负主调节器的角色。MiR-128在出生后前脑神经元缺乏miR-128的小鼠中发生致命性癫痫发作，突显了miR-128在脑功能中的重要性。因此，miR-128在神经元中的过表达可以减轻化学诱导的癫痫发作，并挽救小鼠的生存。这些发现揭示了miR-128是一个以前未知的神经元活动的关键调节因子，具有开发新的抗癫痫治疗方法的潜力。MiR-128的主要调控功能强调了控制miR-128表达水平以及miR-128进入神经元靶点的机制的重要性。我们发现，钙调神经磷酸酶/NFAT活性是神经元发育和功能中的一个重要信号通路，控制着神经元中miR-128的表达。最重要的是，神经元钙调神经磷酸酶缺乏的小鼠会出现类似于miR-128缺乏的小鼠的致命性癫痫综合征。这些发现为钙调神经磷酸酶/NFAT信号在控制miR-128表达中的作用提供了一个强有力的迹象。钙调神经磷酸酶/NFAT介导的miR-128表达的调节机制将在本提案中讨论。该提案还提出了一种调节miR-128效应器功能的新机制。初步数据表明，miR-128对其mRNA靶标的访问受miR-128序列、非编码诱骗RNA的调控。这一调节miR-128效应器功能的新机制将在实验中使用独特的小鼠模型进行探索，该模型具有神经元特异性miR-128诱骗RNA的失活或过表达，并结合我们实验室已建立的分子、电生理和行为方法。MiR-128在神经元信号转导中的中心作用使其成为潜在的癫痫治疗干预的靶点。利用人类Drave型综合征的小鼠模型，该提案将探索神经元miR-128调制用于治疗这种疾病的潜力。Drave型综合征是最严重、最常见的癫痫治疗形式之一。为了使这项研究更接近实际抗癫痫治疗的发展，我们将探索外源表达的miR-128的抗癫痫潜力。MIR-128将通过神经营养腺相关病毒(AAV)被传递到特定的神经元，AAV目前被认为是在小鼠和人类体内传递基因最可靠的载体。总之，我们的建议描述了一种新的非编码RNA机制的高度创新和假设驱动的研究，该机制用于控制神经元信号和活动，具有很强的应用于人类癫痫治疗的潜力。

 DESCRIPTION (provided by applicant): The current project addresses a novel regulatory mechanism of neuronal activity by microRNAs and its role in controlling animal behavior and epilepsy. We found that a neuron-enriched microRNA, miR-128, acts as a negative master modulator of neuronal signaling responses in mice. The importance of the miR-128 in brain function is underscored by the development of fatal epileptic seizures in mice that lack miR-128 in postnatal forebrain neurons. Accordingly, overexpression of miR-128 in neurons attenuates chemically-induced seizures and rescues survival in mice. These findings reveal miR-128 as a previously unknown key regulator of neuronal activity with a potential for the development of novel anti-epileptic therapeutic approaches. The major regulatory function of miR-128 highlights the importance of the mechanisms that control miR-128 expression levels as well as miR-128 access to its targets in neurons. We found that calcineurin/NFAT activity, an important signaling pathway in neuronal development and function, controls miR-128 expression in neurons. Most importantly, mice with neuronal calcineurin deficiency develop a fatal seizure syndrome similar to the one observed in mice with miR-128 deficiency. These findings provided a strong indication for the role of calcineurin/NFAT signaling in control of miR-128 expression. The mechanism of calcineurin/NFAT-mediated regulation of miR-128 expression will be addressed in this proposal. The proposal also addresses a novel mechanism of regulation of miR-128 effector function. Preliminary data suggest that access of miR-128 to its mRNA targets is regulated by miR-128-sequestring, non-coding decoy RNAs. This novel mechanism of regulation of miR-128 effector function will be explored in experiments using unique mouse models with inactivation or overexpression of the neuron-specific miR-128 decoy RNAs in combination with the molecular, electrophysiological and behavioral approaches that have been established in our laboratory. The central role of miR-128 in neuronal signaling makes this miRNA an attractive target for potential therapeutic intervention of epilepsy. Using a mouse model of the human Dravet syndrome, one the most severe and often treatment resistant forms of epilepsy, the proposal will explore the therapeutic potential of neuronal miR-128 modulation for the treatment of the disease. To bring the research closer to the development of actual antiepileptic therapy, we will explore the antiepileptic potential of exogenously expressed miR-128. MiR-128 will be delivered to defined neurons using neurotrophic adeno-associated viruses (AAV) that are currently considered as the most reliable vehicle for in vivo gene delivery in mice and human. In summary, our proposal describes highly innovative and hypothesis driven studies of a novel non-coding RNA mechanism for controlling neuronal signaling and activity that has a strong potential to be applied for the treatment of human epilepsy.