HIGH-END CRYOEM INSTRUMENT FOR THE UCLA ELECTRON IMAGING CENTER FOR NANOMACHINES

该子项目是利用由NIH/NCRR资助的共享仪器赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是用于资助的，不一定是研究者的机构。描述（由申请人提供）：洛杉矶的加州大学（UCLA）的加州纳米系统研究所（CNSI）的长期目标是为尖端纳米生物学和生物医学研究创造一个有利的跨学科环境。作为这一目标的一个组成部分，纳米机器电子成像中心（EICN）的建立是为了满足先进成像技术的迫切需要，以可视化纳米尺度的大分子机器，并了解其作用机制。这一高端共享仪器提案寻求为EICN购买SOOkV场发射枪电子显微镜所需资金的50%（160万美元），以通过电子低温显微镜（cryoEM）和断层扫描（ET）增强我们正在进行的广泛的纳米机器，细胞器，病毒和细菌细胞的三维（3D）结构研究。对用户友好的、高分辨率的、具有断层扫描能力的电子低温显微镜仪器的关键需求在多个层面上是合理的：高分辨率电子显微镜将为十几个主要用户提供必要的仪器，这些用户具有NIH资助的研究项目，这些项目需要通过cryoEM以亚纳米分辨率或通过cryoET以分子分辨率进行结构测定。目前，加州大学洛杉矶分校校园内没有工作的cryoEM仪器。加州理工学院邻近的帕萨迪纳地区的冷冻ET电子冷冻显微镜由于当地用户已经满负荷运行，加州大学洛杉矶分校的教职员工无法使用。因此，通过获得申请中描述的高端电子低温显微镜，将大大增强基于UCLA的研究。高分辨率电子成像将成为加州大学洛杉矶分校已经建立的非常强大的结构生物学研究社区的组成部分。新的高端EM仪器，以及完善的X射线晶体学，高分辨率NMR光谱学和分子建模专业知识将为渴望扩大其当前生物医学和纳米生物学研究项目范围的教师提供宝贵的资源，包括cryoEM和cryoET。新仪器还将满足高分辨率数据的关键要求，将cryoEM重建的包络推到近原子分辨率。不同的生物结构及其高度变化的架构提供了丰富的数据来源，用于开发和完善高分辨率cryoEM的方法，这不仅有利于我们的努力，也有利于一般的电子成像社区。识别经常是次级/次要用户与积极的联邦资金表明，有跨多个部门/机构的自然科学和工程学院，以及加州大学洛杉矶分校医学院，可能会大大受益于高端仪器的收购的主要兴趣。

This subproject is one of many research subprojects utilizing the resources provided by a Shared Instrumentation Grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the grant, which is not necessarily the institution for the investigator. DESCRIPTION (provided by applicant): The long-term goal of the California NanoSystems Institute (CNSI) at the University of California at Los Angeles (UCLA) is to create an enabling and cross-disciplinary environment for cutting-edge nanobiology and biomedical research. As an integral part of this goal, the Electron Imaging Center for Nanomachines (EICN) is established to meet the pressing need of advanced imaging techniques for visualizing macromolecular machineries at the nanometer scale and for the understanding of their mechanisms of action. This high-end shared instrumentation proposal seeks 50% of the funds ($1.6M) needed for the purchase of a SOOkV field emission gun electron microscope for EICN to augment our on-going three- dimensional (3D) structural studies of a broad range of nanomachineries, organelles, viruses and bacterial cells by electron cryomicroscopy (cryoEM) and tomography (ET). The critical need for a user-friendly, high- resolution, tomography-capable electron cryomicroscopy instrument is justified at multiple levels: The high-resolution electron microscope will provide essential instrumentation for over a dozen major users with NIH-funded research projects that require structure determinations either at subnanometer resolution by cryoEM or at molecular resolution by cryoET. Currently, there is no working cryoEM instrument on the UCLA campus. The cryoET-capable electron cryomicroscope in the neighboring Pasadena area at Caltech is not accessible to UCLA faculty members due to already full-capacity operation by local users there. Therefore, UCLA-based research would be greatly enhanced by the acquisition of the high-end electron cryomicroscope described in the application. High-resolution electron imaging will become an integral part of the very strong structural biology research community already established at UCLA. The new high-end EM instrumentation, together with the well-established X-ray crystallography, high-resolution NMR spectrometry, and the molecular modeling expertise will provide a valuable resource for faculty members who are eager to expand the scope of their current biomedical and nanobiology research projects to include cryoEM and cryoET. The new instrument will also meet a critical requirement of high-resolution data for pushing the envelope of cryoEM reconstruction to near atomic resolution. The diverse biological structures with their highly varied architectures offer a fertile source of data for developing and refining the methodology of high-resolution cryoEM, which will not only benefit our efforts but also the general electron imaging community at large. The identification often secondary/minor users with active federal funding shows that there is major interest across multiple departments/institutes among the colleges of natural sciences and engineering, as well as the UCLA medical school that may greatly benefit from the acquisition of the high-end instrument.