Impact of HIV-1 Tat protein on cocaine-dopamine transporter interaction

HIV-1 Tat 蛋白对可卡因-多巴胺转运蛋白相互作用的影响

• 批准号: 8690005
• 负责人: Jun Zhu
• 金额: $ 36.62万
• 依托单位: UNIVERSITY OF SOUTH CAROLINA AT COLUMBIA
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8690005
• 关键词: Address; Affect; Amino Acids; Anti-Retroviral Agents; Binding; Binding Sites; Biological Preservation; Brain; Brain region; Cells; Chinese Hamster Ovary Cell; Cocaine; Computer Simulation; Corpus striatum structure; DNA; Data; Development; Disease; Dopamine; Exposure to; Functional disorder; HIV-1; Human; Impairment; Incidence; Individual; Infection; Lead; Lentivirus Vector; Ligand Binding; Link; Mediating; Molecular; Molecular Target; Mutation; Neurocognitive; Neurons; Neurotransmitters; PC12 Cells; Patients; Physiological; Play; Prevalence; Process; Production; Publishing; Rattus; Recording of previous events; Role; Severities; Site; Site-Directed Mutagenesis; Staging; Structure; Structure-Activity Relationship; Synapses; System; Techniques; Testing; Therapeutic; Transfection; Viral; Viral Proteins; Virus; antiretroviral therapy; attenuation; base; brain cell; conformational conversion; dopamine system; dopamine transporter; drug of abuse; improved; insight; molecular dynamics; mutant; neurotransmission; presynaptic; prevent; psychostimulant; public health relevance; research study; tat Protein; uptake

DESCRIPTION (provided by applicant): HIV-1 associated neurocognitive disorders (HAND) remain highly prevalent in the era of effective antiretroviral therapy. HIV-1 infection within CNS system plays a central role in the development of HAND. Drugs of abuse, such as cocaine, have been shown to increase the incidence and exacerbate the severity of HAND by enhancing viral replication. However, the mechanistic links between cocaine and HAND progression remain undefined. Although changes in many neurotransmitter systems may contribute to HAND, the central dopamine (DA) system plays a crucial role in the development of neurocognitive dysfunction in HAND patients and in the control of psychostimulant action of cocaine. The interplay of HIV-1 Tat protein with cocaine augments synaptic DA level and Tat release within dopaminergic brain regions. Long lasting exposure to elevated DA and Tat eventually lead to DA deficit that potentiates severity and accelerates progression of HAND. Antiretroviral agents cannot prevent the production of HIV-1 viral proteins, such as Tat protein, in proviral-containing brain cells. It is unclear how the DA system is altered in HIV-1 positive cocaine abusers. Therefore, there is a pressing need to define the molecular mechanism(s) by which the impaired DA system by HIV-1 infection affects the progression of HAND in concurrent cocaine abusers. Presynaptic DA transporter (DAT), which is critical for neurocognitive function, is a major molecular target for both Tat and cocaine to impact the DA system. In this application, we hypothesize that Tat, via allosteric binding sites in the DAT, potentiates inhibitory effects of cocaine on DA transport, which is the key to DA system dysfunction occurred in HAND patients. Our proposed experiments will investigate how Tat and cocaine interact with the human DAT through their recognition binding sites on human DAT, thereby leading to dysfunction of the DA system. Our strategy encompasses creating a dynamic 3D computational model to predict potential Tat and cocaine binding pocket residues of human DAT, validating these residues via site-directed mutagenesis, and analyzing the consequent functional changes of the Tat and DAT interaction in neuronal cells and primary neurons. The completion of this application will identify molecular targets on the DAT for developing compounds that specifically block Tat binding site(s) in DAT and stabilize physiological dopaminergic tone, which should be beneficial to the preservation of neurocognitive function in patients with HAND in concurrent cocaine abusers.

描述（由申请人提供）：在有效的抗逆转录病毒疗法的时代，HIV-1相关的神经认知障碍（手）仍然很普遍。中枢神经系统系统中的HIV-1感染在手发展中起着核心作用。诸如可卡因之类的滥用药物已被证明可以通过增强病毒复制来增加发病率并加剧手的严重程度。但是，可卡因和手进展之间的机械联系仍然不确定。尽管许多神经递质系统的变化可能有助于手动，但中央多巴胺（DA）系统在手动患者的神经认知功能障碍以及可卡因的精神刺激作用中起着至关重要的作用。 HIV-1 TAT蛋白与可卡因的相互作用增强了突触DA水平和多巴胺能脑区域内的TAT释放。长期暴露于升高的DA和TAT最终导致DA赤字，从而增强了严重程度并加速了手的进展。抗逆转录病毒药物无法阻止在病前脑细胞中产生HIV-1病毒蛋白，例如TAT蛋白。目前尚不清楚在HIV-1阳性可卡因滥用器中如何改变DA系统。因此，需要定义分子机制，通过该机制，HIV-1感染受损害的DA系统会影响并发可卡因施用者中的手的进展。突触前DA转运蛋白（DAT）对于神经认知功能至关重要，是TAT和可卡因影响DA系统的主要分子靶标。在此应用中，我们假设TAT通过DAT中的变构结合位点增强了抑制作用 DA运输的可卡因，这是DA系统功能障碍的关键，是手动患者发生的。我们提出的实验将研究TAT和可卡因如何通过人类DAT上的识别结合位点与人DAT相互作用，从而导致DA系统功能障碍。我们的策略包括创建动态3D计算模型，以预测人类DAT的潜在TAT和可卡因结合袋残基，通过位置定向的诱变验证这些残基，并分析神经元细胞和原发性神经元中TAT和DAT相互作用的随之而来的功能变化。该应用程序的完成将确定DAT上的分子靶标，以开发出在DAT中特异性阻断TAT结合位点的化合物并稳定生理多巴胺能张力，这应该有助于在同意可卡因施用者中手动中保留手动认知功能的神经认知功能。