Regulation of Vesicular Glutamate Transport

囊泡谷氨酸运输的调节

• 批准号: 7114960
• 负责人: Susan M. Voglmaier
• 金额: $ 17.02万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7114960
• 关键词: antibody; glutamate transporter; hippocampus; immunofluorescence technique; immunoprecipitation; in situ hybridization; laboratory rabbit; laboratory rat; neurons; neuroregulation; neurotransmitter transport; point mutation; protein binding; protein degradation; protein isoforms; protein localization; protein protein interaction; protein sequence; protein structure function; recombinant proteins; site directed mutagenesis; tissue /cell culture; ubiquitin; vesicle /vacuole; yeast two hybrid system

DESCRIPTION (provided by applicant): The changes in synaptic strength that underlie behavioral phenomena such as learning, memory and addiction, are usually attributed to postsynaptic changes in receptor sensitivity, but they may also reflect presynaptic regulation of the amount of transmitter released. The amount of glutamate per vesicle available for exocytotic release depends on its transport from the cytoplasm into vesicles by a family of vesicular glutamate transporter proteins, VGLUTs. VGLUT1 and 2, which account for the exocytotic release of glutamate by essentially all well-established excitatory neurons, exhibit a mutually exclusive pattern of expression in adult brain that correlates with the probability of transmitter release and the potential for plasticity. VGLUT1 also contains several protein-protein interaction domains not found in VGLUT2. The long-term goal of this K08 Mentored Clinical Scientist Development Award proposal is to understand how differences in the trafficking of VGLUT isoforms contribute to the differences in glutamate release observed at different synapses. The strategy is to study the role of C-terminal sequences in activity and trafficking of the different VGLUT isoforms. We have found that one of the polyproline motifs in the C-terminus of VGLUT1 interacts with proteins involved in synaptic vesicle recycling. We will characterize these interactions and determine whether they regulate glutamate transport by influencing vesicle filling, trafficking, or other aspects of the vesicle cycle. In addition, we will characterize and identify protein interactions with two other internalization motifs in VGLUT1. Together, these motifs may contribute to differences in the speed of vesicle filling, exocytosis and endocytosis in glutamate signaling. Increasing evidence implicates glutamate hypofunction in the pathophysiology of schizophrenia, which may involve changes in glutamate release. Thus, an understanding of the regulation of glutamate storage and release may be important in the targeting of therapeutic agents for schizophrenia

描述（由申请人提供）：诸如学习，记忆和成瘾之类的行为现象基础的突触强度的变化通常归因于受体敏感性的突触后变化，但它们也可能反映出释放发射机量的突触前调节。可用于胞吐释放的每个囊泡的谷氨酸量取决于其通过囊泡谷氨酸转运蛋白vgluts的家族从细胞质转运到囊泡。 VGLUT1和2通过本质上所有已建立的兴奋性神经元来解释谷氨酸的胞吐释放，在成人大脑中表现出相互排斥的表达模式，与发射机释放的可能性和可塑性的潜力相关。 VGLUT1还包含VGLUT2中未发现的几个蛋白质蛋白相互作用域。该K08指导的临床科学家发展奖的长期目标是了解VGLUT同工型贩运差异如何导致在不同突触下观察到的谷氨酸释放的差异。该策略是研究C末端序列在不同VGLUT同工型的活性和运输中的作用。我们发现，VGLUT1的C末端中的一个聚丙烯基序之一与参与突触囊泡回收的蛋白质相互作用。我们将表征这些相互作用，并确定它们是通过影响囊泡填充，贩运还是囊泡周期的其他方面来调节谷氨酸转运。此外，我们将表征和鉴定与VGLUT1中其他两个内部化基序的蛋白质相互作用。总之，这些基序可能导致谷氨酸信号传导中囊泡填充，胞吐和内吞作用的速度差异。越来越多的证据表明，精神分裂症的病理生理学中谷氨酸功能功能低下，这可能涉及谷氨酸释放的变化。因此，对谷氨酸储存和释放的调节的理解对于精神分裂症治疗剂的靶向可能很重要