Regulating Serotonin Transporter Conducting States

调节血清素转运蛋白的传导状态

• 批准号: 7030273
• 负责人: MICHAEL W. QUICK
• 金额: $ 22.27万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-04-01 至 2010-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7030273
• 关键词: 3,4 methylenedioxymethamphetamine; Xenopus oocyte; biological signal transduction; botulinum toxins; calcium ion; calmodulin; calmodulin dependent protein kinase; immunoprecipitation; laboratory rat; membrane potentials; molecular biology; neurons; neuroregulation; neurotransmitter transport; phosphorylation; protein binding; protein protein interaction; protein structure function; serotonin; serotonin transporter; stoichiometry; syntaxin; thalamocortical tract; tissue /cell culture; voltage /patch clamp

DESCRIPTION (provided by applicant): Serotonin (5HT) plays a crucial role in aggression, cognition, eating, mood, motor activity, pain, and sleep. 5HT transporters (SERTs) are neuronal membrane proteins that regulate, via uptake, extracellular 5HT concentrations. SERTs are also of interest because they are targets of therapeutics (e.g., antidepressants) and drugs of abuse (e.g., cocaine, amphetamine). Interestingly, SERTs have multiple conducting states, sometimes functioning as ion channels, and other times functioning more as traditional transporters of 5HT. However, the regulatory factors that determine which state SERT occupies, and the functional roles of these conducting states in neurons that endogenously express SERT are unknown. Preliminary data show that the conducting state that SERT occupies depends on SERT's interaction with other proteins. Aim 1 tests the hypothesis that calcium shifts SERT between its states by influencing this interaction, thus providing a physiological mechanism for regulating SERT function. Aim 2 examines the signal transduction pathways by which calcium influences which state SERT occupies. Aim 3 examines state-dependent differences in 5HT uptake. Aim 4 tests the hypothesis that amphetamine dysregulates the calcium-mediated shift in SERT conductance states, and examines the mechanisms underlying this effect. Aim 5 examines the role that these states play in thalamocortical neurons that endogenously express SERT by examining state-dependent cell excitability in the presence of SERT substrates. The experiments will be performed using biochemical, pharmacological, and electrophysiological approaches in cell expression systems and in neurons that endogenously express SERT. These experiments will add to our understanding of normal SERT function and how drugs of abuse that target SERT may mediate their effects. Understanding the factors that regulate SERT may also be important for the design of strategies useful in the treatment of serotonin transporter-mediated disorders.

描述（由申请人提供）：5-羟色胺（5-HT）在攻击、认知、饮食、情绪、运动活动、疼痛和睡眠中起着至关重要的作用。5 HT转运蛋白（SERT）是神经元膜蛋白，通过摄取调节细胞外5 HT浓度。SERT也是令人感兴趣的，因为它们是治疗剂的靶标（例如，抗抑郁药）和滥用药物（例如，可卡因、安非他明）。有趣的是，SERT具有多种传导状态，有时充当离子通道，其他时候更多地充当5 HT的传统转运体。然而，决定SERT占据哪个状态的调节因子，以及这些传导状态在内源性表达SERT的神经元中的功能作用是未知的。 初步数据表明，SERT占据的导电状态取决于SERT与其他蛋白质的相互作用。目的1检验钙通过影响这种相互作用使SERT在其状态之间转移的假设，从而提供调节SERT功能的生理机制。目的2考察钙影响SERT处于何种状态的信号传导途径。目的3检查5 HT摄取的状态依赖性差异。目的4测试的假设，安非他明失调钙介导的SERT电导状态的转变，并探讨这种影响的机制。目的5探讨这些国家发挥的作用，在丘脑皮质神经元内源性表达SERT通过检查状态依赖性细胞的兴奋性SERT底物的存在下。 实验将在细胞表达系统和内源性表达SERT的神经元中使用生物化学、药理学和电生理学方法进行。这些实验将增加我们对正常SERT功能的理解，以及靶向SERT的滥用药物如何介导其作用。了解调节SERT的因素对于设计治疗5-羟色胺转运蛋白介导的疾病的策略也很重要。