Synaptic dysregulation in a mouse model of Alzheimer's disease

描述（由申请人提供）：直到最近才变得明显的是，海马体中的远端兴奋性突触不同于近端兴奋性突触，并且这些差异赋予远端突触与它们的更近端对应物相同的对神经元输出的影响。类似地，最近才显示与阿尔茨海默病（AD）相关的二化学处理靶向突触并影响结合到其突触后膜的AMPA受体（AMPAR）的数量。拟议的研究将研究距离依赖性突触缩放的机制及其对AD样生化处理的脆弱性，使用AD小鼠模型（5XFAD转基因系）及其非转基因同窝对照中突触的多学科分析。该提案的中心目标是帮助首席研究员建立他的独立性，并确保终身教职，使他能够领导一个旨在了解突触，行为和疾病之间相互作用的重大研究项目。本提案的指导阶段将为申请人提供免疫金电子显微镜和全细胞膜片钳生理学的连续切片培训，培训分别来自其领域的两位专家：Yuri Geinisman博士和纳尔逊Spruston博士。这种多学科的培训将促进申请人的过渡到独立，使他能够设计，执行和解释实验在多个，互补的分析水平。在指导阶段，申请人将确定CA1锥体神经元树突远端区域的突触是否比更近端区域的突触更强，以及5XFAD小鼠中AD连锁基因突变是否破坏了这种突触强度的距离依赖性调节。在独立阶段，申请人将联合收割机结合其在电子显微镜和全细胞膜片钳生理学方面的培训，以确定在对照小鼠的单个树突内，CA 1锥体神经元的树突轴上的突触的数量、大小和可塑性是否受到调节，以及这些参数是否由于A？在5XFAD小鼠中过量产生。总之，拟议的实验将有助于确定突触亚型对海马神经元中位置无关的突触通信的贡献，同时确定突触是否是AD的目标，以及某些突触亚型是否比其他亚型更危险。该提案利用了西北大学的协作环境，包括各种光学和电子显微镜研讨会的培训、细胞生理学实验室培训、期刊俱乐部、小鼠基因分型和计算机编程。此外，培训环境将通过国家研究报告，合作，指导学生和负责任的研究行为的培训，为职业发展提供许多机会。

DESCRIPTION (provided by applicant): Only recently has it become evident that distal excitatory synapses are different from proximal excitatory synapses in the hippocampus, and that these differences confer to distal synapses the same influence on neuronal output as their more proximal counterparts. Similarly, it has been shown only recently that Diochemical processing related to Alzheimer's disease (AD) targets synapses and affects the number of AMPA receptors (AMPARs) bound to their postsynaptic membrane. The proposed research will examine the mechanisms of distance-dependent synaptic scaling and their vulnerability to AD-like biochemical processing using a multi-disciplinary analysis of synapses in a mouse model of AD (the 5XFAD transgenic line) and their nontransgenic littermate controls. The central goal of this proposal is assist the Principal Investigator establish his independence and secure a tenure-track faculty position such that he can lead a major research program aimed at understanding the interplay among synapses, behavior, and disease. The Mentored Phase of this proposal will provide the applicant with training in serial section postembedding immunogold electron microscopy and whole-cell patch-clamp physiology from two experts in their fields: Dr. Yuri Geinisman and Dr. Nelson Spruston, respectively. Such multidisciplinary training will facilitate the applicant's transition to independence by enabling him to design, perform, and interpret experiments at multiple, complementary levels of analysis. In the Mentored Phase, the applicant will determine whether synapses in distal regions of the CA1 pyramidal neuron dendrites are stronger than those in more proximal regions, and whether the AD-linked genetic mutations in 5XFAD mice disrupt this distance-dependent regulation of synaptic strength. During the Independent Phase, the applicant will combine his training in electron microscopy and whole-cell patch-clamp physiology to determine whether the number, size, and plasticity in synapses throughout the dendritic axis of CA1 pyramidal neurons are regulated within single dendrites in control mice, and whether these parameters are dysregulated as a consequence of A? overproduction in 5XFAD mice. Together, the proposed experiments will help identify the contributions of synaptic subtypes to location-independent synaptic communication in hippocampal neurons, while simultaneously determining whether synapses are targeted by AD, and whether some synaptic subtypes are more at risk than others. This proposal takes advantage of the collaborative environment at Northwestern University and includes training at various light and electron microscopy workshops, laboratory-based training in cellular physiology, journal clubs, mouse genotyping, and computer programming. In addition, the training environment will provide numerous opportunities for career development through national research presentations, collaborations, mentoring students, and training on the responsible conduct of research.