Regulating Serotonin Transporter Conducting States

调节血清素转运蛋白的传导状态

• 批准号: 6905859
• 负责人: MICHAEL W. QUICK
• 金额: $ 28.44万
• 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/6905859
• 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（5HT）在侵略，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。 5HT转运蛋白（SERT）是神经元膜蛋白，可通过摄取细胞外5HT浓度来调节。 SERT也引起了人们的关注，因为它们是治疗剂（例如抗抑郁药）和滥用药物（例如可卡因，苯丙胺）的靶标。有趣的是，SERT具有多种导电状态，有时充当离子通道，而其他时间则更多地充当5HT的传统转运蛋白。但是，确定哪种状态SERT占据的调节因素以及这些导电状态在内源表达SERT的神经元中的功能作用尚不清楚。 初步数据表明，SERT所占据的指导状态取决于SERT与其他蛋白质的相互作用。 AIM 1检验了以下假设：钙通过影响这种相互作用的状态在其状态之间转移SERT，从而提供了调节SERT功能的生理机制。 AIM 2检查了钙影响状态SERT占据的信号转导途径。 AIM 3检查了5HT吸收的状态依赖性差异。 AIM 4检验了苯丙胺失调的假设，使钙介导的SERT电导状态的转移不足，并检查了这种作用的基础机制。 AIM 5研究了这些状态在丘脑皮质神经元中发挥的作用，这些神经元在存在SERT底物的存在下通过检查状态依赖性细胞兴奋性来表达SERT的作用。 实验将使用细胞表达系统和内源表达SERT的神经元中的生化，药理学和电生理方法进行。这些实验将增加我们对正常SERT功能的理解，以及针对SERT的滥用药物如何介导其影响。了解调节SERT的因素对于设计有助于治疗5-羟色胺转运蛋白介导的疾病的策略也可能很重要。