Role of the Loop1 Domain in AMPA Receptor Trafficking

描述（由申请人提供）：该研究计划的总体目标是研究AMPA受体的新型运输机制，AMPA受体是大脑快速兴奋性突触传递的主要介质。K99/R 00奖的申请人Wei Lu博士目前是加州大学旧金山分校Roger Nicoll博士实验室的博士后研究员。卢博士的长期研究目标是将联合收割机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成为一名独立的科学家，并获得终身教职。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，并与许多精神疾病的发病机制有关。然而，AMPA受体运输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，在AMPA受体空背景下的分子替代，Lu博士取得了一个新的发现，即迄今为止被忽视的胞质环结构域在将AMPA受体靶向突触中起着重要而特异的作用。由于这种受体运输的机制在现有文献中完全未被探索，他提出通过以下三个具体目标来研究这种胞内环结构域在AMPA受体运输中的功能：1）确定GluA 1亚基的这种环结构域在突触传递和动物行为中的作用（指导阶段）; 2）确定GluA 1环结构域的新结合配偶体在AMPA受体运输中的作用（独立阶段）; 3）检验GluA 3环结构域在AMPA受体运输中起作用的假设（独立阶段）。将采用双全细胞电压钳记录、外向膜片记录、生化和行为测定以及分子生物学工具来解决具体目标。卢博士的职业发展计划包括在Nicoll博士的实验室接受神经生理学的指导，在Edwards博士的实验室接受生物化学的指导，并在指导阶段在UCSF接受专业培训。在指导阶段，卢博士将获得新的研究和职业技能，并发表2-3篇高质量的科学论文，从而促进他向独立的过渡。卢博士的研究项目的公共卫生相关性包括提供对学习和记忆的机械见解，以及各种精神疾病的病因学，包括自闭症，抑郁症，精神分裂症和精神发育迟滞。由于精神疾病影响着美国数百万人，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贩运与多种神经系统疾病有关，目前有几种靶向AMPAR的化合物正在临床上用于治疗多种精神疾病。通过AMPAR Loop 1区域调节AMPAR运输的新机制代表了理解AMPAR运输调节的基础神经科学研究的重大进展，因此将为设计针对AMPAR的有效治疗药物提供新的知识。! !

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. ! !