Reelin Signaling and Function in Cocaine Response

精神兴奋剂滥用是一场公共卫生危机，影响着美国数百万人， 造成深刻的经济、社会和个人伤害。然而，尽管吸毒过量的人数迅速增加， 与可卡因等兴奋剂药物有关的死亡，仍然没有批准的兴奋剂治疗方案 滥用障碍精神兴奋剂药物通过明确的信号传导机制发挥作用， 多巴胺能神经传递的神经核（NAc），一个关键的奖励相关的大脑结构， 整合来自不同大脑区域的信息，直接影响动机行为。此外，可卡因 引起NAc中中型棘神经元（MSN）的表观遗传和转录重组， 细胞信号传导和突触功能的不适应转变。我们的初步数据表明，Reln的表达 编码大量分泌的细胞外基质蛋白Reelin的mRNA，富集在 被可卡因强烈激活的MSN。尽管Reelin基因敲除的动物表现出对 精神兴奋剂和Reelin在其他大脑的突触可塑性和记忆形成中发挥着关键作用 区域，Reelin在可卡因相关的细胞和行为适应中的作用从未被研究过。在 在这个提议中，我们将测试一个总体假设，即Reelin信号是适应不良所必需的。 可卡因在NAc中的分子、生理和行为效应。本提案的具体目标1将 联合收割机基于双向CRISPR的操作和单细胞RNA测序，以确定Reelin 信号传导影响对可卡因和多巴胺受体活化的转录应答。具体目标2将 使用体外和体内单个单位记录和离体切片电生理学来检验假设， Reelin通过调节MSN的生理和突触特性来调节可卡因反应。最后， 具体目标3将使用细胞特异性体内Reelin操作与以下行为测定的组合： 可卡因和自然奖励，以测试的假设，Reelin增强可卡因的行为效果。 总之，这些实验将确定在NAc中的Reelin靶基因，剖析分子信号通路， Reelin改变MSN功能和生理的机制，并确定Reelin在NAc中的表达是否 调节可卡因相关的行为可塑性这些研究将揭示基本的机制， Reelin有助于精神兴奋反应，并将为未来的实验铺平道路，以探索如何 这种独特的表达Reln的细胞群有助于激发行为。

Psychostimulant abuse is a public health crisis that affects millions of individuals in the United States and results in profound economic, social, and individual harm. However, despite rapid increases in overdose deaths linked to stimulant drugs like cocaine, there are still no approved therapeutic options for stimulant abuse disorders. Psychostimulant drugs act through well-defined signaling mechanisms to elevate dopaminergic neurotransmission in the nucleus accumbens (NAc), a key reward-linked brain structure that integrates information from diverse brain regions to directly influence motivated behavior. Further, cocaine causes epigenetic and transcriptional reorganization in medium spiny neurons (MSNs) in the NAc, promoting maladaptive shifts in cell signaling and synaptic function. Our preliminary data indicates that expression of Reln mRNA, which codes for the large secreted extracellular matrix protein Reelin, is enriched in a subpopulation of MSNs that are robustly activated by cocaine. Although Reelin knockout animals exhibit impaired response to psychostimulants and Reelin plays a critical role in synaptic plasticity and memory formation in other brain regions, the role of Reelin in cocaine-related cellular and behavioral adaptations has never been studied. In this proposal, we will test the overarching hypothesis that Reelin signaling is required for the maladaptive molecular, physiological, and behavioral effects of cocaine in the NAc. Specific Aim 1 of this proposal will combine bidirectional CRISPR-based manipulations and single-cell RNA sequencing to determine how Reelin signaling impacts transcriptional responses to cocaine and dopamine receptor activation. Specific Aim 2 will use in vitro and in vivo single unit recordings and ex vivo slice electrophysiology to test the hypothesis that Reelin regulates cocaine response by modulation of physiological and synaptic properties of MSNs. Finally, Specific Aim 3 will use cell-specific in vivo Reelin manipulations in combination with behavioral assays of cocaine and natural reward to test the hypothesis that Reelin enhances the behavioral effects of cocaine. Together, these experiments will identify Reelin target genes in the NAc, dissect molecular signaling pathways by which Reelin alters MSN function and physiology, and determine whether Reelin expression within the NAc modulates cocaine-related behavioral plasticity. These studies will reveal fundamental mechanisms by which Reelin contributes to psychostimulant response, and will pave the way for future experiments to explore how this unique Reln-expressing cell population contributes to motivated behavior.