Synaptogyrin-3 promotes behavioral resilience and protects against cocaine-induced dopaminergic adaptations

项目总结 突触素-3(SYG3)是一种对可卡因敏感的突触囊泡蛋白，其功能尚未完全确定。 可卡因使用障碍的背景。SYG3在含有多巴胺的神经元中高表达，并直接 与多巴胺转运体(DAT)相互作用，提示在突触多巴胺动力学中发挥作用。初步 我们实验室的研究表明，可卡因的断裂点在增强的累进比率时间表上，a “动机”的行为学指标与可卡因自身的中脑边缘SYG和DAT水平呈负相关 给老鼠注射药物。此外，我发现VTA多巴胺神经元中SYG3的过度表达减少 焦虑样行为并改变多巴胺系统功能。因此，这项建议的目标是 研究SYG3、DAT和可卡因自我给药之间的关系。我的首要假设 是先天高水平的SYG3诱导弹性行为表型并防止可卡因诱导 多巴胺功能障碍。我将通过回答以下3个具体问题来仔细研究这一假设：(1)什么 可卡因断裂点和SYG3水平之间的反向关系？(2)SYG3的过度表达 在VTA中，多巴胺神经元减少可卡因的自我给药行为？(3)SYG3在VTA中的过度表达 VTA多巴胺神经元保护可卡因诱导的多巴胺功能障碍？我们将追求这些目标 使用行为和神经化学技术，包括情感行为测试，可卡因自身 管理，病毒操作，以及分子和神经化学分析-所有这些都是为了确定 SYG3影响可卡因的服用行为和可卡因引起的多巴胺功能障碍。拟议的研究 意义重大，因为FDA没有批准用于治疗可卡因使用障碍的药物疗法。由此产生的结果是 该提案将进一步将相对未知的突触囊泡蛋白SYG3描述为一种富有成效的细胞 药物疗法治疗可卡因使用障碍的目标。

PROJECT SUMMARY Synatptogyrin-3 (SYG3) is a cocaine-sensitive synaptic vesicle protein that is yet to be fully characterized in the context of cocaine use disorder. SYG3 is highly expressed in dopamine-containing neurons and directly interacts with the dopamine transporter (DAT), suggesting a role in synaptic dopamine dynamics. Preliminary studies from our laboratory suggest that cocaine breakpoint on a progressive ratio schedule of reinforcement, a behavioral proxy for “motivation”, negatively correlates with mesolimbic SYG and DAT levels in cocaine self- administering rats. Moreover, I found that overexpression of SYG3 in VTA dopamine neurons decreases anxiety-like behavior and alters dopamine system function. Therefore, the objective of this proposal is to examine the relationship between SYG3, the DAT, and cocaine self-administration. My overarching hypothesis is that high innate levels of SYG3 induce a resilient behavioral phenotype and prevent cocaine-induced dopamine dysfunction. I will peruse this hypothesis by answering the following 3 specific questions: (1) What drives the inverse relationship between cocaine breakpoint and SYG3 levels? (2) Will overexpression of SYG3 in VTA dopamine neurons reduce cocaine self-administration behaviors? (3) Will overexpression of SYG3 in VTA dopamine neurons protect against cocaine-induced dopamine dysfunction? We will pursue these aims using both behavioral and neurochemical techniques, including affective behavioral tests, cocaine self- administration, viral manipulations, as well as molecular and neurochemical analyses—all to determine if SYG3 influences cocaine-taking behavior and cocaine-induced dopamine dysfunction. The proposed research is significant, since there is no FDA approved pharmacotherapy for cocaine use disorder. The results from this proposal will further characterize the relatively unknown synaptic vesicle protein, SYG3, as a fruitful cellular target for pharmacotherapeutics to treat cocaine use disorder.