Proteomic and Transcriptional Analysis of Cilia-Dependent Dopamine Receptor 1 Signaling

摘要 多巴胺能信号的调节对许多神经疾病具有治疗潜力，包括 运动障碍、药物成瘾和焦虑症。一种很有希望的调制方法 多巴胺能通路涉及靶向特定的多巴胺受体以差异调节个体 信号通路。然而，我们对多巴胺受体信号的理解仍然存在重大差距 阻碍了这样的努力。我们发现多巴胺受体1(D1)动态定位于初级纤毛 在几个大脑区域的神经元上，包括纹状体。初级纤毛是一种细胞附属物，提供 关键的感觉和信号功能。现已知，许多人类疾病是由基因缺陷引起的。 初级纤毛。值得注意的是，我们仍然对初级纤毛如何影响神经元功能知之甚少，尽管 事实上，哺乳动物大脑中的大多数中枢神经元都有初级纤毛。初级纤毛是 受限制的隔室和选定的G蛋白偶联受体(GPCRs)，如D1，靶向于 神经元中的纤毛膜。GPCR信号的下游效应器也定位于神经元纤毛， 这表明初级纤毛支持专门的非突触多巴胺能信号。事实上，我们有 发现破坏表达d1的神经元中的纤毛会导致d1信号的缺失，以及 基础运动活动和肥胖。在本提案中，我们将使用尖端方法来确定 纤毛在表达D1的神经元中作用的分子机制并提供了关键的洞察 纤毛在D1信号转导中的重要性。这项工作的成果将从根本上促进我们对 纹状体中的D1信号，并可能暗示纤毛特异性因子作为治疗的新靶点。

ABSTRACT Modulation of dopaminergic signaling has therapeutic potential for numerous neurological conditions, including movement disorders, drug addiction, and anxiety disorders. One promising approach for modulation of dopaminergic pathways involves targeting specific dopamine receptors to differentially regulate individual signaling pathways. Yet, significant gaps in our understanding of dopamine receptor signaling remain and hinder such efforts. We have discovered that dopamine receptor 1 (D1) dynamically localizes to primary cilia on neurons in several brain regions, including the striatum. Primary cilia are cellular appendages that provide critical sensory and signaling functions. Numerous human diseases are now known to be caused by defects in primary cilia. Remarkably, we still know very little about how primary cilia impact neuronal function, despite the fact that most, if not all, central neurons in the mammalian brain possess a primary cilium. Primary cilia are restricted compartments and select G protein-coupled receptors (GPCRs), such as D1, are targeted to the ciliary membrane in neurons. Downstream effectors of GPCR signaling also localize to neuronal cilia, suggesting that primary cilia support specialized non-synaptic dopaminergic signaling. Indeed, we have discovered that disrupting cilia in D1-expressing neurons results in deficient D1 signaling, as well as reduced basal locomotor activity and obesity. In this proposal we will use cutting-edge approaches to identify the molecular mechanisms underlying the role of cilia in D1-expressing neurons and provide critical insight into the importance of cilia in D1 signaling. The outcomes of this work will fundamentally advance our understanding of D1 signaling in the striatum and may implicate cilia-specific factors as novel targets for therapeutics.