Defining the cell-type specific role of histone acetyltransferase KAT2a in nucleus accumbens D1 medium spiny neurons as a driver of cocaine use disorder

可卡因使用障碍(CUD)给公共卫生带来了巨大的负担，特别是因为没有FDA- 批准的治疗这种疾病的药物疗法。CUD的发生和维持是由生理因素驱动的 大脑内的分子变化导致与吸食可卡因有关的不良适应行为 寻找。这种失调的一个关键神经元群体是表达中棘的多巴胺1受体。 伏核(NAC)内的神经元(D1MSN)。这些细胞被急性可卡因激活，经历 在反复接触可卡因后的生理和转录可塑性，并被可卡因- 驱使他们寻找毒品的相关线索。虽然它们在药物诱导行为中的因果作用已经被确定， 可卡因诱导的调节失调的分子机制仍然知之甚少。的目标是 这项提议是为了定义染色质调节--通过最近发现的可卡因诱导的染色质 修饰酶[赖氨酸乙酰转移酶2a(KAT2a)]-是参与动机的关键底物 服用并寻找可卡因。在我们的初步数据中，我们提供了一系列详细的蛋白质组生物信息学研究 通过这一点，我们确定KAT2a是大规模转录失调的上游调节因子 无论是男性还是女性，都与吸食可卡因有关。我们还表明，突变会导致 仅在D1MSN中损害其功能的KAT2a极大地损害了可卡因的自我管理并破坏了 D1MSN的生理反应。我推测KAT2a在NAC D1MSN中起作用以控制可卡因 自我给药和线索诱导的寻求通过调节基线和对D1MSN活性的反应 与毒品有关的刺激。 为了解决这个问题，我将把小鼠体内的可卡因自身给药与病毒介导的基因转移结合起来。 以及清醒和行为正常的动物的光学成像。在目标1中，我将定义KAT2a在D1MSN中的角色 在吸食可卡因的动机、可卡因的奖赏敏感性和线索诱导的寻求中起作用。在《目标2》中，我会 使用光学成像来定义KAT2a在基线和可卡因反应时如何改变D1MSN的活性。在AIM 3，我将确定KAT2a在清醒和行为中对可卡因相关线索的D1MSN反应中的作用 并确定这些神经动力学与寻求毒品行为之间的关系。本课程的培训目标是 建议书将提供必要的技术和概念专业知识，以调查转录和 物质使用障碍的表观遗传机制。最后，实验结果将定义一个细胞 男性和女性CUD的类型特异性神经表观遗传机制。

Cocaine use disorder (CUD) imposes a large burden on public health, particularly because there are no FDA- approved pharmacotherapies for the disorder. The onset and maintenance of CUD is driven by physiological and molecular changes within the brain that lead to maladaptive behavior associated with cocaine taking and seeking. A key neuronal population in this dysregulation is dopamine 1 receptor expressing medium spiny neurons (D1 MSNs) in the nucleus accumbens (NAc). These cells are activated by acute cocaine, undergo physiological and transcriptional plasticity following repeated cocaine exposure, and are recruited by cocaine- associated cues to drive drug seeking. While their causal role in drug-induced behavior has been identified, the molecular mechanisms underlying cocaine-induced dysregulation remains poorly understood. The goal of this proposal is to define how chromatin regulation – through a recently identified cocaine-induced chromatin modifying enzyme [lysine acetyltransferase 2a (KAT2a)] – is a key substrate involved in the motivation to take and seek cocaine. We present in our preliminary data a detailed series of proteomic bioinformatic studies through which we identified KAT2a as an upstream regulator of the wide-scale transcriptional dysregulation associated with cocaine exposure in the NAc of both males and females. We also show that mutations to KAT2a that impair its function only in D1 MSNs greatly impair cocaine self-administration and disrupt physiological responses in D1 MSNs. I hypothesize that KAT2a acts within NAc D1 MSNs to control cocaine self-administration and cue-induced seeking via regulating D1 MSN activity at baseline and in response to drug-associated stimuli. To address this question, I will combine cocaine self-administration in mice with viral-mediated gene transfer and optical imaging in awake and behaving animals. In Aim 1, I will define the role that KAT2a in D1 MSNs plays in motivation to consume cocaine, cocaine reward sensitivity, and cue-induced seeking. In Aim 2, I will use optical imaging to define how KAT2a alters D1 MSN activity at baseline and in response to cocaine. In Aim 3, I will define the role of KAT2a in D1 MSN responses to cocaine-associated cues in awake and behaving animals and determine how these neural dynamics relate to drug-seeking behavior. The training goals in this proposal will provide the technical and conceptual expertise necessary to investigate the transcriptional and epigenetic mechanisms underlying substance use disorder. Finally, the experimental findings will define a cell type-specific neuroepigenetic mechanism of CUD in males and females.