Cell Type Specific Genetic Manipulation to Dissect Cholinergic Interneuron Function and Plasticity in a Symptomatic Model of DYT1 Dystonia

项目摘要/摘要 胆碱能神经元(CHI)是纹状体环路的一个中枢成分，但人们对此知之甚少。相当可观的 文献强烈表明，气功能障碍与异常运动的发病机制有关，特别是在肌张力障碍患者 以及帕金森病中左旋多巴引起的运动障碍。这些研究的一个共同主题是不适应 塑料变化导致CHI输出和连接异常，促进运动功能障碍。的中心目标是 这一建议是为了促进对CHIS引起的细胞和突触机制的理解。 在最近验证的运动障碍模型中采用新的选择性遗传和化学策略 DYT1肌张力障碍。 条件性敲除所有纹状体神经元的TorsinA(使用Dlx5/6-Cre；“DLX-CKO”)导致选择性 纹状体背外侧神经退行性变。CHI退行性变的发生与青少年的发病大致一致 这些小鼠的异常扭转运动和选择性的迟缓异常也存在于尸检中 DYT1受试者的组织。这些运动被用来抑制毒扁豆碱的相同化合物所抑制 DYT1肌张力障碍患者的治疗，建立模型治疗有效性并建议分享 人类肌张力障碍的病理生理学。存活下来的纹状体脑增大，极度兴奋，并接受 异常的突触输入。选择性消融这些存活的CHI抑制异常扭曲，牵涉到 这些细胞是异常运动的关键贡献者。根据这些数据，我们假设 幸存儿童的适应不良会导致运动功能障碍。 成功完成拟议的研究将从根本上促进对适应不良的理解 CHI功能和连通性驱动异常运动的机制，信息非常重要 治疗多发性纹状体疾病。我们将首先通过检验纹状体发育的必要性来解释我们的假设 通过选择性地将Torsin A恢复到这些细胞而导致的异常运动产生的功能障碍(目标1) 超越了目前这些因素之间的联系。我们将确定是否出现胆碱能功能障碍 主要来自内在的CHI异常或对传入反应的缺陷(目标2)，并由 目标1和目标2将进行翻译研究(目标3)，测试是否直接调节生存活动 Chis可以抑制肌张力障碍样运动。因此，这项提案具有非常重要的意义，因为它将定义 基于电路的运动功能障碍模型，将为靶向治疗的设计提供信息。

Project Summary/Abstract Cholinergic neurons (ChIs) are a central but poorly understood element of striatal circuitry. A considerable literature strongly implicates ChI dysfunction in the pathogenesis of abnormal movements, especially in dystonia and levodopa-induced dyskinesias in Parkinson disease. A common theme of these studies is that maladaptive plastic changes cause aberrant ChI output and connectivity, promoting motor dysfunction. The central goal of this proposal is to advance understanding of the cellular and synaptic mechanisms through which ChIs cause motor dysfunction by employing novel selective genetic and chemical strategies in a recently validated model of DYT1 dystonia. Conditional Knock Out of torsinA from all striatal neurons (using Dlx5/6-Cre; “Dlx-CKO”) causes selective neurodegeneration of dorsolateral striatal ChI. ChI degeneration occurs roughly coincident with the juvenile onset of abnormal twisting movements in these mice, and selective ChI abnormalities are also present in postmortem tissue from DYT1 subjects. These movements are suppressed by the same anti-muscarinic compounds used to treat patients with DYT1 dystonia, establishing model therapeutic validity and suggesting shared pathophysiology with human dystonia. Surviving striatal ChIs are enlarged and hyperexcitable, and receive aberrant synaptic inputs. Selective ablation of these surviving ChI suppresses abnormal twisting, implicating these cells as key contributors to abnormal movements. Based on these data, we hypothesize that maladaptations in surviving ChIs drive motor dysfunction. Successful completion of the proposed studies will fundamentally advance understanding of maladaptive mechanisms whereby ChI function and connectivity drive abnormal movements, information highly significant for multiple striatal diseases. We will first address our hypothesis by testing the necessity of striatal ChI dysfunction in abnormal movement generation by selectively restoring torsinA to these cells (Aim 1), decisively moving beyond the current association between these factors. We will determine if cholinergic dysfunction arises primarily from intrinsic ChI abnormalities or defects in how they respond to afferents (Aim 2), and, informed by Aims 1 and 2, will pursue translational studies (Aim 3) testing whether directly modulating the activity of surviving ChIs can suppress dystonic-like movements. This proposal is therefore highly signifiant because it will define a circuit-based model of motor dysfunction that will inform the design of targeted therapeutics.