Role of the Loop1 Domain in AMPA Receptor Trafficking

描述(申请人提供)：本研究计划的总体目标是研究AMPA受体的一种新的运输机制，AMPA受体是大脑中快速兴奋性突触传递的主要媒介。K99/R00奖的申请者陆伟博士目前是加州大学旧金山分校罗杰·尼科尔博士实验室的博士后研究员。卢博士的长期研究目标是将生化技术与电生理学和遗传学相结合，研究突触可塑性的分子机制。卢博士的长期职业目标是在终身教职的学术职位上确立自己作为一名独立科学家的地位。AMPA受体进出突触是突触可塑性的主要机制，突触可塑性是学习和记忆的细胞模型，与许多精神疾病的发病机制有关。然而，AMPA受体贩运的分子基础在很大程度上仍然难以捉摸。通过使用一种创新的方法，即在AMPA受体零背景中进行分子替换，Lu博士有了一个新的发现，即一个迄今被忽视的细胞质环域在将AMPA受体靶向突触的过程中发挥着重要而特殊的作用。由于这种受体转运的机制在现有文献中完全没有被探索，他建议通过以下特定目的来研究这个细胞内环域在AMPA受体转运中的功能：1)确定GluA1亚单位的这个环域在突触传递和动物行为中的作用(指导阶段)；2)确定GluA1环域的新的结合伙伴在AMPA受体转运中的作用(独立阶段)；3)检验GluA3环域在AMPA受体转运中发挥作用的假设(独立阶段)。将使用双全细胞电压钳记录、外向外贴片记录、生化和行为分析以及分子生物学工具来解决特定的目标。卢博士的职业发展计划包括在尼科尔博士的实验室接受神经生理学指导，在爱德华兹博士的实验室接受生物化学指导，以及在指导阶段在加州大学旧金山分校接受专业培训。导师阶段将帮助卢博士向独立过渡，为他提供新的研究和职业技能，并发表2-3篇高质量的科学论文。卢博士的研究项目与公共卫生相关，包括提供对学习和记忆的机械性见解，以及各种精神疾病的病因，包括自闭症、抑郁症、精神分裂症和精神发育迟滞。由于精神疾病在美国影响着数百万人，卢博士的研究将在分子水平上产生新的知识，为这些精神疾病设计有效的治疗试剂。 公共卫生相关性：AMPAR的贩运与多种神经系统疾病有关，几种以AMPAR为靶点的化合物目前正在临床上治疗各种精神疾病。AMPAR Loop1区域调控AMPAR转运的新机制代表了基础神经科学研究在了解AMPAR转运调控方面的重大进展，从而将为设计针对AMPAR治疗精神疾病的有效治疗试剂创造新的知识。！！

DESCRIPTION (provided by applicant): The overall goal of this research program is to investigate a novel trafficking mechanism for the AMPA receptor that is the major mediator of fast excitatory synaptic transmission in the brain. The applicant for the K99/R00 award, Dr. Wei Lu, currently is a postdoctoral fellow working in Dr. Roger Nicoll's lab at UCSF. Dr. Lu's long- term research goal is to combine biochemical techniques with electrophysiology and genetics to study the molecular mechanisms for synaptic plasticity. Dr. Lu's long-term career goal is to establish himself as an independent scientist in a tenure-track academic position. AMPA receptor trafficking into and out of synapses is a major mechanism for synaptic plasticity that is a cellular model for learning and memory and is implicated in the pathogenesis of many mental illnesses. However, molecular underpinnings for AMPA receptor trafficking remain largely elusive. By using an innovative approach, the molecular replacement in an AMPA receptor null- background, Dr. Lu has made a novel discovery that a hitherto overlooked cytoplasmic loop domain plays an essential and specific role in targeting AMPA receptors to the synapse. As this mechanism for receptor trafficking is completely unexplored in the existing literature, he proposes to study the function of this intracellular loop domain in AMPA receptor traficking by adresing folowing thre specific aims: 1) to determine the role for this loop domain of the GluA1 subunit in synaptic transmission and animal behavior (mentored phase); 2) to determine the role of a novel binding partner of the GluA1 loop domain in AMPA receptor trafficking (independent phase); 3) to test the hypothesis that the GluA3 loop domain plays a role in AMPA receptor trafficking (independent phase). Dual whole-cell voltage-clamp recordings, outside-out patch recordings, biochemical and behavioral assays, and molecular biological tools will be employed to address the specific aims. Dr. Lu's career development plan includes receiving mentorship in neurophysiology in Dr. Nicoll's lab, receiving mentorship in biochemistry in Dr. Edwards's lab and professional trainings at UCSF during the mentored phase. The mentored phase will facilitate Dr. Lu's transition to independence by equipping him with new research and career skills and by publishing 2-3 high quality scientific papers. The public health relevance of Dr. Lu's research program includes providing mechanistic insights into learning and memory, and into the etiology of a variety of mental illnesses, including autism, depression, schizophrenia and mental retardation. As mental illness affects millions of people in the United States, Dr. Lu's research will generate novel knowledge at the molecular level for designing effective therapeutic reagents for these mental disorders. PUBLIC HEALTH RELEVANCE: AMPAR trafficking has been implicated in a variety of neurological diseases, and several compounds targeting AMPARs are currently in clinical for a variety of mental illnesses. The novel mechanism for regulating AMPAR trafficking by AMPAR Loop1 region represents a significant progress in basic neuroscience research for understanding the regulation of AMPAR trafficking, and thus will generate novel knowledge for designing effective therapeutic reagents targeting AMPARs for mental illness. ! !