Reelin Signaling and Function in Cocaine Response

精神刺激性药物滥用是一种公共健康危机，影响到美国数百万人和 造成严重的经济、社会和个人伤害。然而，尽管服药过量迅速增加 与可卡因等刺激性药物有关的死亡，目前仍没有批准的兴奋剂治疗方案 虐待障碍。精神刺激剂药物通过明确的信号机制作用于 伏核(NAC)中的多巴胺能神经传递，这是一种关键的奖赏相关脑结构， 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 导致NAC中棘神经元(MSN)的表观遗传和转录重组，促进 细胞信号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，在一个亚群中富含 被可卡因强烈激活的MSN。尽管Reelin基因敲除动物表现出对 精神刺激剂和Reelin在其他脑的突触可塑性和记忆形成中起关键作用 在这些区域，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……里面 在这项提议中，我们将检验最重要的假设，即适应不良需要Reelin信号 可卡因对NAC的分子、生理和行为影响。本提案的具体目标1将 结合基于CRISPR的双向操作和单细胞RNA测序来确定如何卷曲 信号影响对可卡因和多巴胺受体激活的转录反应。特定目标2将 使用体外和活体单个单位记录和体外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的反应。最后， 特定目标3将使用体内细胞特异性的Reelin操作，并结合 可卡因和自然奖赏来检验Reelin增强可卡因行为效应的假设。 总之，这些实验将识别NAC中的Reelin靶基因，剖析分子信号通路 通过Reelin改变MSN的功能和生理，并确定Reelin在NAC中的表达 调节可卡因相关的行为可塑性。这些研究将揭示以下基本机制： Reelin有助于心理刺激反应，并将为未来的实验探索如何 这种独特的表达Reln的细胞群有助于动机行为。

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.